The articles on these pages represent the culmination of 3 years of effort by the Society of Hospital Medicine (SHM) Glycemic Control Task Force. In this brief introduction, we share a few insights and comments about this multidisciplinary collaborative effort to address the care of inpatients with hyperglycemia.

The SHM Glycemic Control Task Force was assembled in 2005, with the intent of improving the care of inpatients with diabetes. We wished to provide hospitalists and quality improvement teams with an understanding of the best practices to achieve safe glycemic control in the hospital. Additionally, this task force sought to identify tools and strategies to obtain improved communication, medication safety, education, and other aspects of care. A distinguished panel of experts attended their inaugural meeting in Chicago, Illinois, in October 2005, including hospitalists, endocrinologists, nurses, case managers, diabetes educators, and pharmacists. A roster of the individuals and organizations is given in the Appendix.

Many members of the SHM Glycemic Control Task Force also participated in the Call to Action consensus conference1 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA) in January 2006. Both groups identified several barriers to improvement, and methods to overcome these barriers were summarized in this quote from the Consensus Conference,

Successful implementation of a program to improve glycemic control in the inpatient setting should include the following components:

• 1

  An appropriate level of administrative support.

• 2

  Formation of a multidisciplinary steering committee to drive the development of initiatives.

• 3

  Assessment of current processes, quality of care, and barriers to practice change.

• 4

  Development and implementation of interventions including standardized order sets, protocols, policies, and algorithms with associated educational programs.

• 5

  Metrics for evaluation.

Both groups also called for a web‐based compendium of tested tools and strategies to assist local improvement teams.

After countless hours of development and revision by the SHM Glycemic Task Force and the Resource Room team, such a compendium addressing all of these components was launched on the SHM web site in the form of the SHM Glycemic Control Resource Room.2 A comprehensive implementation guide3 is available for downloading free of charge, and serves as the centerpiece of the Resource Room. Subsequently, this comprehensive but somewhat sprawling implementation guide evolved into these more sophisticated and concise articles.410 The topics include a review of the rationale for improving inpatient glycemic control,4 an important call for standardizing the metrics of glycemic control,9 subcutaneous insulin regimens and order sets,5, 6 insulin infusion protocols,7 transitions of care,8 and the business case for glycemic control.10 It has been a long but rewarding and educational journey, drawing on the collective experience from dozens of institutions in all kinds of inpatient care settings. A few key points and insights seem worth sharing.

THE IMPROVEMENT EFFORT IS NOT JUST ABOUT REACHING A GLYCEMIC TARGET

The term glycemic control team and the label for the SHM Glycemic Control Task Force itself are somewhat misnomers. Task Force members agree that desirable institutional glycemic target ranges should be established, but many among us believe the glycemic targets endorsed by national guidelines (ref ADA and AACE guidelines)11, 12 are too stringent. Furthermore, we believe that achieving glycemic control is just one small part of the needed improvement efforts. Uncontrolled hyperglycemia is common, potentially dangerous, and largely preventable with safe and proven methodsbut so are the iatrogenic hypoglycemia episodes, substandard education, poor communication, lack of care coordination, and inadequate monitoring that typify care of the hyperglycemic inpatient. We address all of these issues and urge the adoption of this broader perspective.

THE EVIDENCE IS INCOMPLETEBUT ACTION IS REQUIRED

We acknowledge gaps and inconsistencies in the literature surrounding inpatient diabetes management and the controversy around tight glycemic control. In many cases, high level evidence is not available to guide the formulation of protocols, order sets, or other improvement tools. We are all struck by how pervasive the lack of evidence is. What is the best metric for inpatient glycemic control or hypoglycemia? What is the best regimen for a patient on continuous tube feedings? Which insulin infusion protocol is superior in reaching and maintaining a glycemic target range?

Rather than make no recommendations or accept negative inertia on the basis of less than perfect evidence, we make recommendations based on the best evidence available. When we make recommendations based on consensus opinion or the collective experience from dozens of medical centers, rather than randomized trials, we have made every effort to make this clear in the text of the articles. In our view, incomplete evidence is not an adequate excuse to persist in the unacceptable status quo, clinging on to methods (such as sliding scale insulin regimens) that have been shown to be ineffective and potentially dangerous.1315

COLLABORATION PAYS DIVIDENDS

It takes a multidisciplinary approach to make substantial improvement in glycemic control of hospitalized patients. By the same token, it is unlikely that any one group can advance the national agenda for improved care as well as a multidisciplinary coordinated effort. Team members, especially the endocrinologists and hospitalists, collaborated skillfully throughout this effort. The hospitalists learned a tremendous amount from the expertise, insight, and mastery of the literature, offered by the endocrinology members, whereas the endocrinologists appreciated the front line expertise and practical quality improvement approach of the hospitalist members. This collaboration serves as a model for making guidelines and best practices become more of a practical reality for a variety of important clinical problems. Hospitalists can partner with and learn from a variety of other disciplines, while they assist these disciplines on effective improvement and implementation efforts. On a more personal note, this work has fostered mutual respect, friendship, and career long collaborative opportunities. The potential for these same opportunities with nursing, pharmacy, and all medical and surgical fields seems compelling and exciting.

THERE'S MORE!

By the time this is published, these articles will be integrated into the third iteration of the SHM Glycemic Control Resource Room. This online resource has already undergone 2 major revisions since its inception just a few years ago, reflecting SHM's dedication to the continuous improvement of the products and services that it offers. The Glycemic Control Implementation Guide and Resource Room will continue to be a work in progress. We highly encourage and welcome constructive criticism and feedback via E‐mail to [email protected]. The resource room contains a wealth of tools, slide shows, literature reviews, and links, in addition to the core articles published in this Supplement.

NEXT STEPS

More research and demonstration projects are obviously needed in this field. Local collaborative activities have sprung up in several cities and regions, as well as Glycemic Control Champions courses. A longitudinal mentoring program (similar to the SHM Venous Thromboembolism Prevention collaborative) would undoubtedly be beneficial, and may become available within the next year or so. These items and more will be promoted and posted in the resource room whenever possible.

Finally, the next step is up to you and the institutions in which you workyou have to decide, as individuals and institutions, if you believe the status quo is good enough. We believe that if you look, you'll find the care of our inpatients with diabetes and hyperglycemia disturbingly suboptimal, and hope that the work of the SHM Glycemic Control Task Force can help you rapidly improve on this state of affairs.

APPENDIX: GLYCEMIC CONTROL TASK FORCE

The Society of Hospital Medicine thanks all the members of the Glycemic Control Task Force, who encompass a distinguished panel of experts with representation from the AACE, ADA, ACP, and other organizations whose expertise was essential to the construction of the Glycemic Control Resource Room and the Implementation Guide for Glycemic Control and Prevention of Hypoglycemia.

The articles on these pages represent the culmination of 3 years of effort by the Society of Hospital Medicine (SHM) Glycemic Control Task Force. In this brief introduction, we share a few insights and comments about this multidisciplinary collaborative effort to address the care of inpatients with hyperglycemia.

The SHM Glycemic Control Task Force was assembled in 2005, with the intent of improving the care of inpatients with diabetes. We wished to provide hospitalists and quality improvement teams with an understanding of the best practices to achieve safe glycemic control in the hospital. Additionally, this task force sought to identify tools and strategies to obtain improved communication, medication safety, education, and other aspects of care. A distinguished panel of experts attended their inaugural meeting in Chicago, Illinois, in October 2005, including hospitalists, endocrinologists, nurses, case managers, diabetes educators, and pharmacists. A roster of the individuals and organizations is given in the Appendix.

Many members of the SHM Glycemic Control Task Force also participated in the Call to Action consensus conference1 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA) in January 2006. Both groups identified several barriers to improvement, and methods to overcome these barriers were summarized in this quote from the Consensus Conference,

Successful implementation of a program to improve glycemic control in the inpatient setting should include the following components:

• 1

  An appropriate level of administrative support.

• 2

  Formation of a multidisciplinary steering committee to drive the development of initiatives.

• 3

  Assessment of current processes, quality of care, and barriers to practice change.

• 4

  Development and implementation of interventions including standardized order sets, protocols, policies, and algorithms with associated educational programs.

• 5

  Metrics for evaluation.

Both groups also called for a web‐based compendium of tested tools and strategies to assist local improvement teams.

After countless hours of development and revision by the SHM Glycemic Task Force and the Resource Room team, such a compendium addressing all of these components was launched on the SHM web site in the form of the SHM Glycemic Control Resource Room.2 A comprehensive implementation guide3 is available for downloading free of charge, and serves as the centerpiece of the Resource Room. Subsequently, this comprehensive but somewhat sprawling implementation guide evolved into these more sophisticated and concise articles.410 The topics include a review of the rationale for improving inpatient glycemic control,4 an important call for standardizing the metrics of glycemic control,9 subcutaneous insulin regimens and order sets,5, 6 insulin infusion protocols,7 transitions of care,8 and the business case for glycemic control.10 It has been a long but rewarding and educational journey, drawing on the collective experience from dozens of institutions in all kinds of inpatient care settings. A few key points and insights seem worth sharing.

THE IMPROVEMENT EFFORT IS NOT JUST ABOUT REACHING A GLYCEMIC TARGET

The term glycemic control team and the label for the SHM Glycemic Control Task Force itself are somewhat misnomers. Task Force members agree that desirable institutional glycemic target ranges should be established, but many among us believe the glycemic targets endorsed by national guidelines (ref ADA and AACE guidelines)11, 12 are too stringent. Furthermore, we believe that achieving glycemic control is just one small part of the needed improvement efforts. Uncontrolled hyperglycemia is common, potentially dangerous, and largely preventable with safe and proven methodsbut so are the iatrogenic hypoglycemia episodes, substandard education, poor communication, lack of care coordination, and inadequate monitoring that typify care of the hyperglycemic inpatient. We address all of these issues and urge the adoption of this broader perspective.

THE EVIDENCE IS INCOMPLETEBUT ACTION IS REQUIRED

We acknowledge gaps and inconsistencies in the literature surrounding inpatient diabetes management and the controversy around tight glycemic control. In many cases, high level evidence is not available to guide the formulation of protocols, order sets, or other improvement tools. We are all struck by how pervasive the lack of evidence is. What is the best metric for inpatient glycemic control or hypoglycemia? What is the best regimen for a patient on continuous tube feedings? Which insulin infusion protocol is superior in reaching and maintaining a glycemic target range?

Rather than make no recommendations or accept negative inertia on the basis of less than perfect evidence, we make recommendations based on the best evidence available. When we make recommendations based on consensus opinion or the collective experience from dozens of medical centers, rather than randomized trials, we have made every effort to make this clear in the text of the articles. In our view, incomplete evidence is not an adequate excuse to persist in the unacceptable status quo, clinging on to methods (such as sliding scale insulin regimens) that have been shown to be ineffective and potentially dangerous.1315

COLLABORATION PAYS DIVIDENDS

It takes a multidisciplinary approach to make substantial improvement in glycemic control of hospitalized patients. By the same token, it is unlikely that any one group can advance the national agenda for improved care as well as a multidisciplinary coordinated effort. Team members, especially the endocrinologists and hospitalists, collaborated skillfully throughout this effort. The hospitalists learned a tremendous amount from the expertise, insight, and mastery of the literature, offered by the endocrinology members, whereas the endocrinologists appreciated the front line expertise and practical quality improvement approach of the hospitalist members. This collaboration serves as a model for making guidelines and best practices become more of a practical reality for a variety of important clinical problems. Hospitalists can partner with and learn from a variety of other disciplines, while they assist these disciplines on effective improvement and implementation efforts. On a more personal note, this work has fostered mutual respect, friendship, and career long collaborative opportunities. The potential for these same opportunities with nursing, pharmacy, and all medical and surgical fields seems compelling and exciting.

THERE'S MORE!

By the time this is published, these articles will be integrated into the third iteration of the SHM Glycemic Control Resource Room. This online resource has already undergone 2 major revisions since its inception just a few years ago, reflecting SHM's dedication to the continuous improvement of the products and services that it offers. The Glycemic Control Implementation Guide and Resource Room will continue to be a work in progress. We highly encourage and welcome constructive criticism and feedback via E‐mail to [email protected]. The resource room contains a wealth of tools, slide shows, literature reviews, and links, in addition to the core articles published in this Supplement.

NEXT STEPS

More research and demonstration projects are obviously needed in this field. Local collaborative activities have sprung up in several cities and regions, as well as Glycemic Control Champions courses. A longitudinal mentoring program (similar to the SHM Venous Thromboembolism Prevention collaborative) would undoubtedly be beneficial, and may become available within the next year or so. These items and more will be promoted and posted in the resource room whenever possible.

Finally, the next step is up to you and the institutions in which you workyou have to decide, as individuals and institutions, if you believe the status quo is good enough. We believe that if you look, you'll find the care of our inpatients with diabetes and hyperglycemia disturbingly suboptimal, and hope that the work of the SHM Glycemic Control Task Force can help you rapidly improve on this state of affairs.

APPENDIX: GLYCEMIC CONTROL TASK FORCE

The Society of Hospital Medicine thanks all the members of the Glycemic Control Task Force, who encompass a distinguished panel of experts with representation from the AACE, ADA, ACP, and other organizations whose expertise was essential to the construction of the Glycemic Control Resource Room and the Implementation Guide for Glycemic Control and Prevention of Hypoglycemia.

The articles on these pages represent the culmination of 3 years of effort by the Society of Hospital Medicine (SHM) Glycemic Control Task Force. In this brief introduction, we share a few insights and comments about this multidisciplinary collaborative effort to address the care of inpatients with hyperglycemia.

The SHM Glycemic Control Task Force was assembled in 2005, with the intent of improving the care of inpatients with diabetes. We wished to provide hospitalists and quality improvement teams with an understanding of the best practices to achieve safe glycemic control in the hospital. Additionally, this task force sought to identify tools and strategies to obtain improved communication, medication safety, education, and other aspects of care. A distinguished panel of experts attended their inaugural meeting in Chicago, Illinois, in October 2005, including hospitalists, endocrinologists, nurses, case managers, diabetes educators, and pharmacists. A roster of the individuals and organizations is given in the Appendix.

Many members of the SHM Glycemic Control Task Force also participated in the Call to Action consensus conference1 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA) in January 2006. Both groups identified several barriers to improvement, and methods to overcome these barriers were summarized in this quote from the Consensus Conference,

Successful implementation of a program to improve glycemic control in the inpatient setting should include the following components:

• 1

  An appropriate level of administrative support.

• 2

  Formation of a multidisciplinary steering committee to drive the development of initiatives.

• 3

  Assessment of current processes, quality of care, and barriers to practice change.

• 4

  Development and implementation of interventions including standardized order sets, protocols, policies, and algorithms with associated educational programs.

• 5

  Metrics for evaluation.

Both groups also called for a web‐based compendium of tested tools and strategies to assist local improvement teams.

After countless hours of development and revision by the SHM Glycemic Task Force and the Resource Room team, such a compendium addressing all of these components was launched on the SHM web site in the form of the SHM Glycemic Control Resource Room.2 A comprehensive implementation guide3 is available for downloading free of charge, and serves as the centerpiece of the Resource Room. Subsequently, this comprehensive but somewhat sprawling implementation guide evolved into these more sophisticated and concise articles.410 The topics include a review of the rationale for improving inpatient glycemic control,4 an important call for standardizing the metrics of glycemic control,9 subcutaneous insulin regimens and order sets,5, 6 insulin infusion protocols,7 transitions of care,8 and the business case for glycemic control.10 It has been a long but rewarding and educational journey, drawing on the collective experience from dozens of institutions in all kinds of inpatient care settings. A few key points and insights seem worth sharing.

THE IMPROVEMENT EFFORT IS NOT JUST ABOUT REACHING A GLYCEMIC TARGET

The term glycemic control team and the label for the SHM Glycemic Control Task Force itself are somewhat misnomers. Task Force members agree that desirable institutional glycemic target ranges should be established, but many among us believe the glycemic targets endorsed by national guidelines (ref ADA and AACE guidelines)11, 12 are too stringent. Furthermore, we believe that achieving glycemic control is just one small part of the needed improvement efforts. Uncontrolled hyperglycemia is common, potentially dangerous, and largely preventable with safe and proven methodsbut so are the iatrogenic hypoglycemia episodes, substandard education, poor communication, lack of care coordination, and inadequate monitoring that typify care of the hyperglycemic inpatient. We address all of these issues and urge the adoption of this broader perspective.

THE EVIDENCE IS INCOMPLETEBUT ACTION IS REQUIRED

We acknowledge gaps and inconsistencies in the literature surrounding inpatient diabetes management and the controversy around tight glycemic control. In many cases, high level evidence is not available to guide the formulation of protocols, order sets, or other improvement tools. We are all struck by how pervasive the lack of evidence is. What is the best metric for inpatient glycemic control or hypoglycemia? What is the best regimen for a patient on continuous tube feedings? Which insulin infusion protocol is superior in reaching and maintaining a glycemic target range?

Rather than make no recommendations or accept negative inertia on the basis of less than perfect evidence, we make recommendations based on the best evidence available. When we make recommendations based on consensus opinion or the collective experience from dozens of medical centers, rather than randomized trials, we have made every effort to make this clear in the text of the articles. In our view, incomplete evidence is not an adequate excuse to persist in the unacceptable status quo, clinging on to methods (such as sliding scale insulin regimens) that have been shown to be ineffective and potentially dangerous.1315

COLLABORATION PAYS DIVIDENDS

It takes a multidisciplinary approach to make substantial improvement in glycemic control of hospitalized patients. By the same token, it is unlikely that any one group can advance the national agenda for improved care as well as a multidisciplinary coordinated effort. Team members, especially the endocrinologists and hospitalists, collaborated skillfully throughout this effort. The hospitalists learned a tremendous amount from the expertise, insight, and mastery of the literature, offered by the endocrinology members, whereas the endocrinologists appreciated the front line expertise and practical quality improvement approach of the hospitalist members. This collaboration serves as a model for making guidelines and best practices become more of a practical reality for a variety of important clinical problems. Hospitalists can partner with and learn from a variety of other disciplines, while they assist these disciplines on effective improvement and implementation efforts. On a more personal note, this work has fostered mutual respect, friendship, and career long collaborative opportunities. The potential for these same opportunities with nursing, pharmacy, and all medical and surgical fields seems compelling and exciting.

THERE'S MORE!

By the time this is published, these articles will be integrated into the third iteration of the SHM Glycemic Control Resource Room. This online resource has already undergone 2 major revisions since its inception just a few years ago, reflecting SHM's dedication to the continuous improvement of the products and services that it offers. The Glycemic Control Implementation Guide and Resource Room will continue to be a work in progress. We highly encourage and welcome constructive criticism and feedback via E‐mail to [email protected]. The resource room contains a wealth of tools, slide shows, literature reviews, and links, in addition to the core articles published in this Supplement.

NEXT STEPS

More research and demonstration projects are obviously needed in this field. Local collaborative activities have sprung up in several cities and regions, as well as Glycemic Control Champions courses. A longitudinal mentoring program (similar to the SHM Venous Thromboembolism Prevention collaborative) would undoubtedly be beneficial, and may become available within the next year or so. These items and more will be promoted and posted in the resource room whenever possible.

Finally, the next step is up to you and the institutions in which you workyou have to decide, as individuals and institutions, if you believe the status quo is good enough. We believe that if you look, you'll find the care of our inpatients with diabetes and hyperglycemia disturbingly suboptimal, and hope that the work of the SHM Glycemic Control Task Force can help you rapidly improve on this state of affairs.

APPENDIX: GLYCEMIC CONTROL TASK FORCE

The Society of Hospital Medicine thanks all the members of the Glycemic Control Task Force, who encompass a distinguished panel of experts with representation from the AACE, ADA, ACP, and other organizations whose expertise was essential to the construction of the Glycemic Control Resource Room and the Implementation Guide for Glycemic Control and Prevention of Hypoglycemia.

Recently, there has been a heightened interest in improving the quality and safety of the management of diabetes and hyperglycemia in the hospital.1 While observational data strongly suggests an association of hyperglycemia with morbidity and mortality in adults on general medicine and surgery units, clinical research has not yet defined the best practices for managing hyperglycemia in the hospital outside the intensive care unit (ICU). As a result, many physicians do not have a well‐formulated approach to managing hyperglycemia in the noncritically ill hospital patient, and the use of insulin therapy to attain targeted blood glucose (BG) control is often subject to practice variability, leading to suboptimal glycemic outcomes.

Practical guidelines for the management of this common clinical problem have been formulated by experts in the field, based on understanding of the physiology of glucose and insulin dynamics, the characteristics of currently available insulin preparations, and clinical experience. In 2004, in Clement et al.,2 the American Diabetes Association published a technical review promoting the use of physiologic (basal‐nutritional‐correction dose) insulin regimens in the hospital to achieve targeted glycemic outcomes. This approach has been disseminated via review articles,3 and more recently, a randomized, controlled trial demonstrated that hospitalized type 2 diabetes patients experienced better glycemic control when treated with a physiologic insulin regimen than when treated with sliding‐scale insulin alone.4 The Society of Hospital Medicine has assembled a Glycemic Control Task Force, which is charged with providing physicians and hospitals with practical tools to improve the safety and efficacy of diabetes management in the hospital. One product of this work is an educational module that serves as a tutorial on the best practice for the management of diabetes and hyperglycemia in the noncritically ill hospital patient.5 This article is based on that module, and provides a practical summary of the key concepts that will allow clinicians to confidently employ physiologic insulin regimens when caring for their hospital patients.

Case: Ms. X is a 56‐year‐old obese woman with type 2 diabetes mellitus who is admitted for treatment of an infected diabetes‐related foot ulcer. The patient will be allowed to eat dinner in a couple of hours, but the surgeons have requested that she be kept nothing by mouth (NPO) after midnight for surgical debridement in the morning. Her current weight is 100 kg, and her recent glycemic control can be summarized as having BG values that are usually in the mid‐200s (mg/dL) and a recent glycosylated hemoglobin (HbA1C) measurement of 10.9%. Her home medical regimen includes glipizide 10 mg daily, metformin 1000 mg twice daily, and 20 units of neutral protamine hagadorn (NPH) insulin at bedtime. Her blood glucose in the Emergency Department is 289 mg/dL. How should this patient's blood glucose be managed in the hospital?

PHARMACOLOGIC CONTROL OF BG IN THE HOSPITAL: INSULIN IS THE ANTIHYPERGLYCEMIC AGENT OF CHOICE

Although oral antihyperglycemic agents are frequently used in the outpatient setting, there are many potential disadvantages to using these medications in acutely ill hospital patients, as shown in Figure 1.2, 3 Oral antihyperglycemic agents, in general, are difficult to quickly titrate to effect, and have side effects that can limit their use in the hospital. Metformin can lead to lactic acidosis when it is used in clinical situations that predispose to lactate production (eg, renal failure, circulatory failure, hypoxemia). Therefore, metformin should be held in patients who have, or are at risk for, these conditions, each of which may be encountered in the hospital. Also, agents that stimulate the release of insulin, such as sulfonylureas, should be held in patients with variable nutritional intake, to prevent hypoglycemia. In contrast, insulin acts rapidly, responds in a timely fashion to dose titrations, and can be used effectively in virtually all patients and clinical situations to control BG levels. This makes insulin the treatment of choice for hyperglycemia in the hospital. Insulin can be administered via subcutaneous doses or as an intravenous infusion for cases in which rapid titration is the goal. Intravenous insulin infusions are the preferred mode of insulin delivery in the ICU setting, and may be appropriate for some noncritically ill patients in hospitals that have developed systems to safely provide them on general wards. Subcutaneous insulin is most commonly used in the noncritically ill patient population and is the focus of this article.

Figure 1

Although insulin is the drug of choice for managing hyperglycemia in the hospital, there are some situations when it is appropriate to continue oral antihyperglycemic medications in the hospital. These agents may be continued in hospitalized patients who are clinically stable, and who have normal nutritional intake, normal BG levels, and stable renal and cardiac function. They may also be started or resumed in the hospital if they are to be included in the discharge medication regimen once the patient is clinically stable and if it has been assured that contraindications to their use no longer exist.

Ms. X should be treated with a more robust (physiologic) insulin regimen. This statement would be true, even if she were not an inpatient with a foot infection. Her glycemic control is currently poor, as evidenced by her high HbA1C and her elevated admission BG, and is unlikely to be appreciably improved with the addition of any pharmacologic agent other than insulin. The glipizide should be held, as the patient will be NPO after midnight. Most experts would recommend holding the metformin at this time as well, since the patient will be undergoing a surgical procedure in the morning that places her at risk for predisposing factors to lactic acidosis.

INPATIENT GLYCEMIC TARGETS

At present, recommended glycemic targets for noncritically ill hospital patients are based entirely on expert opinion, as there have been no clinical studies directly comparing different glycemic targets in this patient population. However, the American College of Endocrinology, the American Association of Clinical Endocrinologists, and the American Diabetes Association do provide recommendations about glycemic targets for inpatients (Table 1).6, 7 Although controversial, these recommendations make it clear that uncontrolled hyperglycemia is no longer the accepted standard of care for hospitalized patients, and illustrate the consensus of expert opinion on the subject. Of note, many hospitals are adopting glycemic targets that are less stringent than those shown in Table 1, recognizing the challenges of controlling BG levels in hospitalized patients, and the potential risk for hypoglycemia when lower BG targets are used. Each hospital's glycemic control champions must reach consensus on a target BG range for their institution. In practice this range has been 90110 mg/dL for the lower BG limit and 140180 mg/dL for the upper BG limit. It is also important to note that the recommendations from professional organizations emphasize the need to individualize BG targets, based on the clinical circumstances of each patient.

Ms. X is exhibiting glycemic values far outside of the recommended upper limit of 180 mg/dL, and treatment with insulin monotherapy is the most appropriate strategy in this case.

PHYSIOLOGIC (BASAL‐BOLUS, PLUS CORRECTION DOSE) INSULIN

The management of hyperglycemia and diabetes in the inpatient setting is challenging due to the many changes that patients experience in the hospital. Hospitalized patients often experience changes in their nutritional intake and their medication regimen. In addition, hospitalized patients usually experience the stress of acute illness and are treated with medications that might impact glycemic control. Figure 2 lists some of the barriers to achieving glycemic control in hospitalized patients. The inpatient insulin program needs to be flexible enough to allow for maintenance of glycemic control in the face of tumultuous circumstances. This can best be accomplished by the use of a physiologic insulin program. This means using exogenous insulin to mimic normal physiologic insulin activity by providing the correct types and doses of insulin at the correct times.

Figure 2

A physiologic insulin regimen can be conceptualized as having 3 separate components: basal insulin, nutritional (or prandial/meal) insulin, and correction dose (or supplemental) insulin.2 A patient's total daily dose (TDD) of insulin is the sum of all of these, and represents the amount of insulin that a patient requires over the course of 1 day while receiving adequate nutrition. Basal insulin is the insulin normally released continuously by the pancreas, even when fasting. This serves to suppress glucose and ketone production. When nutrition is ingested, there is a surge in the level of glucose in the blood, and this surge is accompanied by rapid secretion of additional insulin to allow for the appropriate utilization of the glucose. The insulin that is secreted in response to nutritional intake is referred to as nutritional insulin. About one‐half of the total daily insulin secreted by a healthy normal human serves a basal function, and about one‐half is secreted in response to nutritional intake.8 Understanding this bit of physiology (the 50/50 rule) is very helpful for creating flexible regimens using exogenous insulin. Although the 50/50 rule is useful in many circumstances, there are some notable exceptions. In some cases, basal insulin might be expected to be less than one‐half of the TDD (eg, enteral feeds, as discussed below). Additional correction dose insulin is given to correct hyperglycemia that occurs despite scheduled doses of basal and nutritional insulin.

It is an important practical consideration to note that when a person with diabetes is acutely ill or stressed, as is commonly the case in the hospital setting, total daily insulin requirements increase. This is due to the action of insulin counterregulatory hormones such as catecholamines, cortisol, growth hormone, and glucagon. The hospitalized patient is therefore likely to require a TDD that is higher than that required when well. This is particularly true for the basal insulin dose. Conversely, insulin requirements will decrease as a patient recovers from acute illness, and it may be necessary to lower insulin doses as BG levels decrease during convalescence.

Exogenous basal insulin is provided as a long‐acting or intermediate‐acting, low‐peaking or nonpeaking insulin (eg, glargine or detemir), that allows for a consistent level of basal insulin (Figure 3). This insulin is provided even when the person is not receiving any nutrition. Although twice daily NPH insulin can be used to provide basal insulin, the peak (as shown in Figure 3) is likely to exceed the level of insulin that is truly required for basal needs, which can result in hypoglycemia. In theory, NPH insulin would be less physiologic than glargine or detemir, although no studies have compared these insulins in the hospital setting. When using NPH insulin as a basal insulin in a patient who is designated NPO, the dose should be reduced by one‐third to one‐half to avoid hypoglycemia that may occur when it peaks.2

Figure 3

Exogenous nutritional insulin must be provided in a way that matches the nutrition that is being provided to the patient. For example, a patient who is receiving nutritional boluses (ie, meals or bolus tube feeds) can be given rapid‐acting insulin (eg, aspart, glulisine, lispro) along with each nutritional bolus to cover the glycemic peak that is caused by the meal. The rapid‐acting analog insulins can also be given at the end of a meal or bolus tube feed for cases in which it is not clear if the nutrition will be well tolerated. A reduction in the insulin dose proportionate to the amount of nutrition actually taken can then be made to decrease the risk of subsequent hypoglycemia. Regular insulin can also be given in anticipation of a meal or tube feed, but its later peak (as shown in Figure 3) requires that it be given 30 minutes before a meal is ingested, the timing of which is a challenge on most nursing units. Patients who are not receiving any nutrition should not receive nutritional insulin. And, patients receiving alternative forms of nutrition will require different nutritional insulin regimens to adequately cover their nutritional glycemic loads, as discussed below.

The separate provision of basal and nutritional insulin results in a highly‐flexible insulin program that can provide basal insulin to patients even when they are not receiving significant nutrition, and can be easily adjusted to provide appropriate nutritional insulin to match actual nutritional delivery.

Correction‐dose insulin is the small amount of insulin that is given to patients, in addition to basal and nutritional insulin, to correct hyperglycemia. Correction‐dose insulin is usually provided as rapid‐acting or regular insulin (usually the same type as the nutritional insulin), and is given in a dose that is specifically designed to reduce the patient's BG back into the target range. It is usually given at the same time as the nutritional insulin in patients who are receiving nutrition (or every 4 to 6 hours in patients who are not). Correction‐dose insulin is often written in a stepped format, to provide the appropriate amount of insulin for a given BG value. It differs from the traditional sliding‐scale in that it is not used alone (but rather as 1 component of a physiologic program), and in that it is customized to match the insulin sensitivity for each patient. Most standardized order sets for subcutaneous insulin provide several different correction‐dose scales to choose from, depending on the patient's weight or total daily insulin requirement.

If correction‐dose insulin is required consistently, or in high doses, it suggests a need to modify the basal and/or nutritional insulin. A proportion of the total number of units of correction‐dose insulin given in the preceding 24 hours can be distributed into basal and nutritional insulin doses for the next day if there is ongoing need for significant correction‐doses of insulin. A well‐designed, physiologic insulin regimen should provide targeted glycemic control, without a need for constantly adding large correctional boluses.

Some insulins do not fit neatly into either basal or nutritional insulin categories. For example, mixed insulins (eg, 70/30, rapid‐analog/NPH mixtures) combine basal and nutritional insulins to form either a double‐peaking insulin or an intermediate‐peaking insulin. The use of this type of insulin makes it impossible to manipulate the basal and nutritional components separately to enable attainment of BG targets. Therefore, the role of this type of insulin is limited in the hospital setting. Mixed insulins may, however, be started once the patient is clinically stable if they will be part of the discharge regimen.

Diabetes and hyperglycemia in the hospitalized patient require active management, and there are no autopilot insulin regimens. The use of sliding scale insulin alone to manage hyperglycemia is a common practice in hospitals.9 However, this is an historic practice that is based on the erroneous idea that BG can be managed with a reactive strategy. When sliding‐scale insulin is used as the sole modality of insulin therapy, insulin is provided only after metabolic control has been lost, and usually does not provide an appropriate dose of insulin, considering basal, nutritional, and correctional needs. The end result is poor glycemic control.9, 10 A recent randomized, controlled trial demonstrated that a physiologic insulin regimen is indeed superior to a standardized insulin sliding‐scale for managing inpatient hyperglycemia.4

Ms. X should be given an insulin regimen that includes basal, nutritional, and correctional components. The provision of separate basal and nutritional insulin will allow the clinicians to provide the patient with basal insulin even when her nutritional insulin is held, and to easily modify her nutritional insulin, depending on her nutritional intake.

PHYSIOLOGIC INSULIN: A PRACTICAL APPROACH

The use of physiologic insulin in the hospital can be facilitated by considering a stepwise approach (Figure 4).5 The first step is to estimate the amount of insulin that the patient will require over the course of a day if taking adequate nutrition (this is the TDD). If the patient has been treated with subcutaneous insulin before being admitted to the hospital, the clinician can use the outpatient TDD to gauge the insulin needs. To do this, the clinician simply adds up the total number of units of insulin that a patient takes at home in a day. Using this method to estimate the patient's TDD can be very helpful, even if the clinician plans to use different types of insulin while the patient is hospitalized. When using this approach, one should consider the patient's prior metabolic control on the existing regimen (ie, if the patient's glycemic control was poor on the preexisting regimen, an increase in the TDD would be necessary). In addition, clinicians should recognize that insulin requirements usually increase when patients are acutely ill, as discussed above. Managing diabetes and hyperglycemia in the hospital is very different than doing so in the outpatient arena, and hospitalists should not feel bound by the outpatient regimen.

Figure 4

In addition, a weight‐based estimation of the TDD can be very helpful in determining a starting dose of insulin in a hospitalized patient (see Figure 5). An estimate of 0.4 units/kg of body weight provides a conservative starting point for the TDD for most patients. Occasionally, a lower starting dose of 0.3 units/kg of body weight might be safer for those patients who are likely to be very sensitive to insulin, or who are otherwise at increased at risk for hypoglycemia (see Figure 5). Patients who are overweight or obese often require considerably higher TDDs in the range of 0.5‐0.6 (or even more) units/kg of body weight. Some may require over 1 unit/kg of body weight for their TDD. Therefore, the doses provided by these calculations represent conservative estimates in most patients. Hospitalists should be able to confidently make these dose estimates and avoid dependence on nonphysiologic regimens such as sliding‐scale insulin alone.

Figure 5

The presence of risk factors for hypoglycemia or hyperglycemia should temper the dose calculations. Clinical conditions associated with hyperglycemia include obesity, certain medications (eg, glucocorticoids, catecholamines, tacrolimus, cyclosporine), and changes in nutritional intake (Figure 2). Clinical conditions associated with hypoglycemia are summarized in Figure 6. It is important to recognize that these calculations are intended to give the clinician a safe and rational starting point for insulin dosing. More important than the calculations is the careful monitoring of BG levels and timely modifications of the insulin regimen that follow.

Figure 6

The second step in developing a physiologic insulin regimen is to determine the patient's nutritional regimen. The third step, then, is to decide how the TDD will be distributed into basal and nutritional insulins, and which insulin will be used for each. As noted above, for most patients, approximately one‐half of the TDD will be provided as basal insulin, and the other one‐half given as nutritional insulin. When patients are receiving nutrition, the insulin must be given in a way that matches the timing of nutrition delivery (eg, with each meal or bolus tube feeding), and provides appropriate insulin coverage for the nutrition that is being provided.

Nutritional insulin will not be given if the patient is not receiving any nutrition, in which case basal insulin and correction‐dose insulin will usually be continued. Table 2 shows the preferred insulin regimens for a variety of different nutritional circumstances, as put forth by the Society of Hospital Medicine (SHM) Glycemic Control Task Force.5

For Ms. X, the first step is to determine a TDD estimate. This patient weighs 100 kg, and is obese. Therefore, a TDD of 0.5 units/kg (50 units) is appropriate. This dose may be an underestimate of her insulin needs, but it is a conservative, reasonable starting point. The patient's basal insulin could be provided by giving one‐half of the TDD as basal insulin, such as glargine, 25 units daily. In this case, the patient will be eating dinner soon, but then will be NPO after midnight for surgery. Appropriate nutritional insulin could be provided by giving one‐third of her total nutritional insulin before this meal as a rapid‐acting insulin analog (25 units nutritional insulin per day divided by 3 meals results in a dose of 8 units per meal). After she eats dinner, additional nutritional insulin will not be given until she resumes her diet postoperatively. While NPO, her basal insulin should be continued, and her blood glucose should be checked every 4‐6 hours. An appropriate correction‐dose insulin scale should be chosen to provide a supplemental insulin dose with each bedside test of the blood glucose level, if and only if, hyperglycemia is present.

Case continued: The patient is given 8 units of lispro insulin before her dinner, and is also given a dose of 25 units of glargine insulin. She is held NPO after midnight and dextrose‐containing fluid is provided intravenously overnight at a maintenance rate. In the morning her blood glucose is 161 mg/dL before surgery. Surgery goes well, and at lunch her blood glucose is 179 mg/dL, and she is given a food tray. However, the patient says that she feels mildly nauseated, and is not sure that she will be able to eat her lunch. How should her nutritional insulin be managed in this situation?

MATCHING NUTRITION AND NUTRITIONAL INSULIN: A DIFFICULT CHALLENGE

It is the provision of the correct type and amount of nutritional insulin at the right time that is most challenging in the hospital. In the hospital, a patient's nutritional intake is often interrupted. Patients might be made NPO as part of the treatment plan, or may not be able to take nutrition by mouth because of specific medical conditions. In some cases, enteral or parenteral feeding is used to replace or enhance oral feeding. Even when alternate routes of nutrition are employed, sudden interruptions in nutrition still remain common (eg, the feeding tube falls out). Ultimately, to provide the best possible care to a diabetes patient, the nutritional insulin that is delivered must match the actual nutritional delivery (Table 2). Ideally, each institution should choose a preferred, standardized approach for each nutritional situation.

Even if institutions standardize their approach to nutritional insulin delivery in general, clinicians must be able to accurately respond to the unplanned variations in nutrition that occur in the hospital. One example of this is the patient who is expected to eat meals, but who becomes suddenly unable to do so, such as in the case above. In cases like this, the best approach is to hold the patient's nutritional insulin and allow the patient to attempt to eat the provided meal. Then, a rapid‐acting insulin analog can be given just after the meal, in proportion to the amount of the meal that was eaten. If the patient really is unable to tolerate any of the meal, then no nutritional insulin is provided. If the patient does tolerate a portion of the meal (eg, 50% of the meal is consumed), then a corresponding amount of insulin is given (eg, 50% of the scheduled nutritional insulin is given). The quick onset of the rapid‐acting insulin analogs allows near‐physiologic effect, even when they are given after the meal.

Ms. X should be allowed to eat as much of the meal as she can tolerate. Afterward, her intake can be assessed, and insulin can be provided in proportion to the amount of the meal that was eaten, as described above.

TYPE 1 DIABETES

Because type 2 diabetes is more prevalent than type 1 diabetes, hospitalists will manage this form of diabetes most often. However, it is crucial that hospitalists are also able to manage type 1 diabetes in the hospital. For the most part, the principles presented in this article apply to all types of diabetes patients. This section outlines some special considerations to remember when caring for type 1 diabetes patients in the hospital that will assure prevention of diabetic ketoacidosis in patients with type 1 diabetes.

Type 1 diabetes patients completely lack endogenous insulin production. Therefore, these patients require exogenous insulin to be provided at all times. Type 1 diabetes patients need to be provided continuous, exogenous basal insulin, even when fasting, to suppress gluconeogenesis and ketone production. Failure to provide basal insulin to a type 1 diabetes patient can lead to the rapid development (in hours) of ketoacidosis. When receiving nutrition, the patient with type 1 diabetes must also be provided with nutritional insulin to control postprandial BGs. Whereas many type 2 diabetes patients may produce sufficient endogenous insulin to meet basal requirements when fasting (ie, they produce enough basal insulin to maintain metabolic stability when they are not taking in nutrition), this is never the case for type 1 diabetes patients.

In addition, type 1 diabetes patients typically exhibit less insulin resistance than type 2 diabetes patients, especially if they are not obese. Therefore, type 1 diabetes patients often have TDDs of insulin that are lower than those of type 2 patients. This is reflected in the recommendations in Figure 5, with the TDD of insulin estimate for a lean type 1 diabetes patient of 0.3 units/kg/day.

CONTINUOUS SUBCUTANEOUS INSULIN INFUSIONS (INSULIN PUMPS) IN THE HOSPITAL

Continuous subcutaneous insulin infusion therapy (CSII), often referred to as insulin pump therapy, involves the use of a pump to provide a continuous flow of subcutaneous basal insulin (usually a rapid‐acting analog) through a needle that is left in place. This basal rate is adjustable, and therefore can be customized to meet variable needs over a 24‐hour period. When the patient takes in nutrition, a bolus of the same insulin is given, via the pump, at a dose that is appropriate to cover the nutritional intake. The advantages of CSII therapy are the capacity for precision and flexibility of the basal insulin delivery (compared to the use of a once‐daily or twice‐daily dose of long‐acting insulin analog), and the lack of a need to inject insulin boluses (which are delivered via the pump). This type of therapy is preferred by some diabetes patients, and although it is not highly prevalent in most areas, it is common enough that hospitalists must have a plan for managing it in their practices.

There are many barriers to the use of CSII in the hospital. Most of these barriers are related to the need for constant management of the pump. Most hospitalists and nurses do not have the expertise to manage this therapy in the hospital. Although the patient (or caregiver) might have the expertise to manage the pump, this is an acceptable option only if the patient is competent to manage the pump. Patient competence to use the pump must be formally assessed and documented, and the patient must agree to perform the many components of care related to managing the pump (eg, documenting the basal rate and boluses given, documenting BGs, providing tubing and other supplies).

Many hospitals currently choose a policy of converting insulin pump therapy to standard subcutaneous insulin treatment for most hospitalized patients. Usually the conversion of CSII to a physiologic subcutaneous insulin regimen (as detailed in this article) is fairly straightforwardthe basal insulin will be given as long‐acting, low‐peaking insulin, and nutritional and correction‐dose insulin can then be added as a rapid‐acting analog, in accord with the patient's needs.

Hospitals that admit a large number of insulin pump patients, or those that choose to use pumps routinely in the hospital, should create a formal policy for pump use.11 It has been suggested that the policy should assure that there is formal assessment of the patient's competence to manage the pump, that there is professional oversight of the pump management (usually via endocrinology and diabetes educator consultation), that contraindications for CSII use are clearly stated, and that there is a formal mechanism for engaging the patient and informing him of his roles and responsibilities (eg, a written agreement). The clinician must write insulin orders in the medical record that specify the basal and bolus insulin doses which are being used. Pump use may be limited to floors where nurses receive at least basic education in the principles of CSII pumps.

CARE TRANSITIONS IN THE HOSPITAL

CONCLUSIONS

Understanding the basic principles of the physiologic (basal, nutritional, and correction‐dose) insulin regimen will allow clinicians to formulate safe and effective insulin regimens in virtually any clinical situation. Simple steps can allow safe estimates of initial doses and titration toward glycemic goals. Additional information and case studies can be found in a Society of Hospital Medicine Task Force Educational Module,5 available online.

Additional resources for improving glycemic control in hospital patients are available online at the Glycemic Control Resource Room (http://www.hospitalmedicine.org/ResourceRoomRedesign/ GlycemicControl.cfm).

Recently, there has been a heightened interest in improving the quality and safety of the management of diabetes and hyperglycemia in the hospital.1 While observational data strongly suggests an association of hyperglycemia with morbidity and mortality in adults on general medicine and surgery units, clinical research has not yet defined the best practices for managing hyperglycemia in the hospital outside the intensive care unit (ICU). As a result, many physicians do not have a well‐formulated approach to managing hyperglycemia in the noncritically ill hospital patient, and the use of insulin therapy to attain targeted blood glucose (BG) control is often subject to practice variability, leading to suboptimal glycemic outcomes.

Practical guidelines for the management of this common clinical problem have been formulated by experts in the field, based on understanding of the physiology of glucose and insulin dynamics, the characteristics of currently available insulin preparations, and clinical experience. In 2004, in Clement et al.,2 the American Diabetes Association published a technical review promoting the use of physiologic (basal‐nutritional‐correction dose) insulin regimens in the hospital to achieve targeted glycemic outcomes. This approach has been disseminated via review articles,3 and more recently, a randomized, controlled trial demonstrated that hospitalized type 2 diabetes patients experienced better glycemic control when treated with a physiologic insulin regimen than when treated with sliding‐scale insulin alone.4 The Society of Hospital Medicine has assembled a Glycemic Control Task Force, which is charged with providing physicians and hospitals with practical tools to improve the safety and efficacy of diabetes management in the hospital. One product of this work is an educational module that serves as a tutorial on the best practice for the management of diabetes and hyperglycemia in the noncritically ill hospital patient.5 This article is based on that module, and provides a practical summary of the key concepts that will allow clinicians to confidently employ physiologic insulin regimens when caring for their hospital patients.

Case: Ms. X is a 56‐year‐old obese woman with type 2 diabetes mellitus who is admitted for treatment of an infected diabetes‐related foot ulcer. The patient will be allowed to eat dinner in a couple of hours, but the surgeons have requested that she be kept nothing by mouth (NPO) after midnight for surgical debridement in the morning. Her current weight is 100 kg, and her recent glycemic control can be summarized as having BG values that are usually in the mid‐200s (mg/dL) and a recent glycosylated hemoglobin (HbA1C) measurement of 10.9%. Her home medical regimen includes glipizide 10 mg daily, metformin 1000 mg twice daily, and 20 units of neutral protamine hagadorn (NPH) insulin at bedtime. Her blood glucose in the Emergency Department is 289 mg/dL. How should this patient's blood glucose be managed in the hospital?

PHARMACOLOGIC CONTROL OF BG IN THE HOSPITAL: INSULIN IS THE ANTIHYPERGLYCEMIC AGENT OF CHOICE

Although oral antihyperglycemic agents are frequently used in the outpatient setting, there are many potential disadvantages to using these medications in acutely ill hospital patients, as shown in Figure 1.2, 3 Oral antihyperglycemic agents, in general, are difficult to quickly titrate to effect, and have side effects that can limit their use in the hospital. Metformin can lead to lactic acidosis when it is used in clinical situations that predispose to lactate production (eg, renal failure, circulatory failure, hypoxemia). Therefore, metformin should be held in patients who have, or are at risk for, these conditions, each of which may be encountered in the hospital. Also, agents that stimulate the release of insulin, such as sulfonylureas, should be held in patients with variable nutritional intake, to prevent hypoglycemia. In contrast, insulin acts rapidly, responds in a timely fashion to dose titrations, and can be used effectively in virtually all patients and clinical situations to control BG levels. This makes insulin the treatment of choice for hyperglycemia in the hospital. Insulin can be administered via subcutaneous doses or as an intravenous infusion for cases in which rapid titration is the goal. Intravenous insulin infusions are the preferred mode of insulin delivery in the ICU setting, and may be appropriate for some noncritically ill patients in hospitals that have developed systems to safely provide them on general wards. Subcutaneous insulin is most commonly used in the noncritically ill patient population and is the focus of this article.

Figure 1

Although insulin is the drug of choice for managing hyperglycemia in the hospital, there are some situations when it is appropriate to continue oral antihyperglycemic medications in the hospital. These agents may be continued in hospitalized patients who are clinically stable, and who have normal nutritional intake, normal BG levels, and stable renal and cardiac function. They may also be started or resumed in the hospital if they are to be included in the discharge medication regimen once the patient is clinically stable and if it has been assured that contraindications to their use no longer exist.

Ms. X should be treated with a more robust (physiologic) insulin regimen. This statement would be true, even if she were not an inpatient with a foot infection. Her glycemic control is currently poor, as evidenced by her high HbA1C and her elevated admission BG, and is unlikely to be appreciably improved with the addition of any pharmacologic agent other than insulin. The glipizide should be held, as the patient will be NPO after midnight. Most experts would recommend holding the metformin at this time as well, since the patient will be undergoing a surgical procedure in the morning that places her at risk for predisposing factors to lactic acidosis.

INPATIENT GLYCEMIC TARGETS

At present, recommended glycemic targets for noncritically ill hospital patients are based entirely on expert opinion, as there have been no clinical studies directly comparing different glycemic targets in this patient population. However, the American College of Endocrinology, the American Association of Clinical Endocrinologists, and the American Diabetes Association do provide recommendations about glycemic targets for inpatients (Table 1).6, 7 Although controversial, these recommendations make it clear that uncontrolled hyperglycemia is no longer the accepted standard of care for hospitalized patients, and illustrate the consensus of expert opinion on the subject. Of note, many hospitals are adopting glycemic targets that are less stringent than those shown in Table 1, recognizing the challenges of controlling BG levels in hospitalized patients, and the potential risk for hypoglycemia when lower BG targets are used. Each hospital's glycemic control champions must reach consensus on a target BG range for their institution. In practice this range has been 90110 mg/dL for the lower BG limit and 140180 mg/dL for the upper BG limit. It is also important to note that the recommendations from professional organizations emphasize the need to individualize BG targets, based on the clinical circumstances of each patient.

Ms. X is exhibiting glycemic values far outside of the recommended upper limit of 180 mg/dL, and treatment with insulin monotherapy is the most appropriate strategy in this case.

PHYSIOLOGIC (BASAL‐BOLUS, PLUS CORRECTION DOSE) INSULIN

The management of hyperglycemia and diabetes in the inpatient setting is challenging due to the many changes that patients experience in the hospital. Hospitalized patients often experience changes in their nutritional intake and their medication regimen. In addition, hospitalized patients usually experience the stress of acute illness and are treated with medications that might impact glycemic control. Figure 2 lists some of the barriers to achieving glycemic control in hospitalized patients. The inpatient insulin program needs to be flexible enough to allow for maintenance of glycemic control in the face of tumultuous circumstances. This can best be accomplished by the use of a physiologic insulin program. This means using exogenous insulin to mimic normal physiologic insulin activity by providing the correct types and doses of insulin at the correct times.

Figure 2

A physiologic insulin regimen can be conceptualized as having 3 separate components: basal insulin, nutritional (or prandial/meal) insulin, and correction dose (or supplemental) insulin.2 A patient's total daily dose (TDD) of insulin is the sum of all of these, and represents the amount of insulin that a patient requires over the course of 1 day while receiving adequate nutrition. Basal insulin is the insulin normally released continuously by the pancreas, even when fasting. This serves to suppress glucose and ketone production. When nutrition is ingested, there is a surge in the level of glucose in the blood, and this surge is accompanied by rapid secretion of additional insulin to allow for the appropriate utilization of the glucose. The insulin that is secreted in response to nutritional intake is referred to as nutritional insulin. About one‐half of the total daily insulin secreted by a healthy normal human serves a basal function, and about one‐half is secreted in response to nutritional intake.8 Understanding this bit of physiology (the 50/50 rule) is very helpful for creating flexible regimens using exogenous insulin. Although the 50/50 rule is useful in many circumstances, there are some notable exceptions. In some cases, basal insulin might be expected to be less than one‐half of the TDD (eg, enteral feeds, as discussed below). Additional correction dose insulin is given to correct hyperglycemia that occurs despite scheduled doses of basal and nutritional insulin.

It is an important practical consideration to note that when a person with diabetes is acutely ill or stressed, as is commonly the case in the hospital setting, total daily insulin requirements increase. This is due to the action of insulin counterregulatory hormones such as catecholamines, cortisol, growth hormone, and glucagon. The hospitalized patient is therefore likely to require a TDD that is higher than that required when well. This is particularly true for the basal insulin dose. Conversely, insulin requirements will decrease as a patient recovers from acute illness, and it may be necessary to lower insulin doses as BG levels decrease during convalescence.

Exogenous basal insulin is provided as a long‐acting or intermediate‐acting, low‐peaking or nonpeaking insulin (eg, glargine or detemir), that allows for a consistent level of basal insulin (Figure 3). This insulin is provided even when the person is not receiving any nutrition. Although twice daily NPH insulin can be used to provide basal insulin, the peak (as shown in Figure 3) is likely to exceed the level of insulin that is truly required for basal needs, which can result in hypoglycemia. In theory, NPH insulin would be less physiologic than glargine or detemir, although no studies have compared these insulins in the hospital setting. When using NPH insulin as a basal insulin in a patient who is designated NPO, the dose should be reduced by one‐third to one‐half to avoid hypoglycemia that may occur when it peaks.2

Figure 3

Exogenous nutritional insulin must be provided in a way that matches the nutrition that is being provided to the patient. For example, a patient who is receiving nutritional boluses (ie, meals or bolus tube feeds) can be given rapid‐acting insulin (eg, aspart, glulisine, lispro) along with each nutritional bolus to cover the glycemic peak that is caused by the meal. The rapid‐acting analog insulins can also be given at the end of a meal or bolus tube feed for cases in which it is not clear if the nutrition will be well tolerated. A reduction in the insulin dose proportionate to the amount of nutrition actually taken can then be made to decrease the risk of subsequent hypoglycemia. Regular insulin can also be given in anticipation of a meal or tube feed, but its later peak (as shown in Figure 3) requires that it be given 30 minutes before a meal is ingested, the timing of which is a challenge on most nursing units. Patients who are not receiving any nutrition should not receive nutritional insulin. And, patients receiving alternative forms of nutrition will require different nutritional insulin regimens to adequately cover their nutritional glycemic loads, as discussed below.

The separate provision of basal and nutritional insulin results in a highly‐flexible insulin program that can provide basal insulin to patients even when they are not receiving significant nutrition, and can be easily adjusted to provide appropriate nutritional insulin to match actual nutritional delivery.

Correction‐dose insulin is the small amount of insulin that is given to patients, in addition to basal and nutritional insulin, to correct hyperglycemia. Correction‐dose insulin is usually provided as rapid‐acting or regular insulin (usually the same type as the nutritional insulin), and is given in a dose that is specifically designed to reduce the patient's BG back into the target range. It is usually given at the same time as the nutritional insulin in patients who are receiving nutrition (or every 4 to 6 hours in patients who are not). Correction‐dose insulin is often written in a stepped format, to provide the appropriate amount of insulin for a given BG value. It differs from the traditional sliding‐scale in that it is not used alone (but rather as 1 component of a physiologic program), and in that it is customized to match the insulin sensitivity for each patient. Most standardized order sets for subcutaneous insulin provide several different correction‐dose scales to choose from, depending on the patient's weight or total daily insulin requirement.

If correction‐dose insulin is required consistently, or in high doses, it suggests a need to modify the basal and/or nutritional insulin. A proportion of the total number of units of correction‐dose insulin given in the preceding 24 hours can be distributed into basal and nutritional insulin doses for the next day if there is ongoing need for significant correction‐doses of insulin. A well‐designed, physiologic insulin regimen should provide targeted glycemic control, without a need for constantly adding large correctional boluses.

Some insulins do not fit neatly into either basal or nutritional insulin categories. For example, mixed insulins (eg, 70/30, rapid‐analog/NPH mixtures) combine basal and nutritional insulins to form either a double‐peaking insulin or an intermediate‐peaking insulin. The use of this type of insulin makes it impossible to manipulate the basal and nutritional components separately to enable attainment of BG targets. Therefore, the role of this type of insulin is limited in the hospital setting. Mixed insulins may, however, be started once the patient is clinically stable if they will be part of the discharge regimen.

Diabetes and hyperglycemia in the hospitalized patient require active management, and there are no autopilot insulin regimens. The use of sliding scale insulin alone to manage hyperglycemia is a common practice in hospitals.9 However, this is an historic practice that is based on the erroneous idea that BG can be managed with a reactive strategy. When sliding‐scale insulin is used as the sole modality of insulin therapy, insulin is provided only after metabolic control has been lost, and usually does not provide an appropriate dose of insulin, considering basal, nutritional, and correctional needs. The end result is poor glycemic control.9, 10 A recent randomized, controlled trial demonstrated that a physiologic insulin regimen is indeed superior to a standardized insulin sliding‐scale for managing inpatient hyperglycemia.4

Ms. X should be given an insulin regimen that includes basal, nutritional, and correctional components. The provision of separate basal and nutritional insulin will allow the clinicians to provide the patient with basal insulin even when her nutritional insulin is held, and to easily modify her nutritional insulin, depending on her nutritional intake.

PHYSIOLOGIC INSULIN: A PRACTICAL APPROACH

The use of physiologic insulin in the hospital can be facilitated by considering a stepwise approach (Figure 4).5 The first step is to estimate the amount of insulin that the patient will require over the course of a day if taking adequate nutrition (this is the TDD). If the patient has been treated with subcutaneous insulin before being admitted to the hospital, the clinician can use the outpatient TDD to gauge the insulin needs. To do this, the clinician simply adds up the total number of units of insulin that a patient takes at home in a day. Using this method to estimate the patient's TDD can be very helpful, even if the clinician plans to use different types of insulin while the patient is hospitalized. When using this approach, one should consider the patient's prior metabolic control on the existing regimen (ie, if the patient's glycemic control was poor on the preexisting regimen, an increase in the TDD would be necessary). In addition, clinicians should recognize that insulin requirements usually increase when patients are acutely ill, as discussed above. Managing diabetes and hyperglycemia in the hospital is very different than doing so in the outpatient arena, and hospitalists should not feel bound by the outpatient regimen.

Figure 4

In addition, a weight‐based estimation of the TDD can be very helpful in determining a starting dose of insulin in a hospitalized patient (see Figure 5). An estimate of 0.4 units/kg of body weight provides a conservative starting point for the TDD for most patients. Occasionally, a lower starting dose of 0.3 units/kg of body weight might be safer for those patients who are likely to be very sensitive to insulin, or who are otherwise at increased at risk for hypoglycemia (see Figure 5). Patients who are overweight or obese often require considerably higher TDDs in the range of 0.5‐0.6 (or even more) units/kg of body weight. Some may require over 1 unit/kg of body weight for their TDD. Therefore, the doses provided by these calculations represent conservative estimates in most patients. Hospitalists should be able to confidently make these dose estimates and avoid dependence on nonphysiologic regimens such as sliding‐scale insulin alone.

Figure 5

The presence of risk factors for hypoglycemia or hyperglycemia should temper the dose calculations. Clinical conditions associated with hyperglycemia include obesity, certain medications (eg, glucocorticoids, catecholamines, tacrolimus, cyclosporine), and changes in nutritional intake (Figure 2). Clinical conditions associated with hypoglycemia are summarized in Figure 6. It is important to recognize that these calculations are intended to give the clinician a safe and rational starting point for insulin dosing. More important than the calculations is the careful monitoring of BG levels and timely modifications of the insulin regimen that follow.

Figure 6

The second step in developing a physiologic insulin regimen is to determine the patient's nutritional regimen. The third step, then, is to decide how the TDD will be distributed into basal and nutritional insulins, and which insulin will be used for each. As noted above, for most patients, approximately one‐half of the TDD will be provided as basal insulin, and the other one‐half given as nutritional insulin. When patients are receiving nutrition, the insulin must be given in a way that matches the timing of nutrition delivery (eg, with each meal or bolus tube feeding), and provides appropriate insulin coverage for the nutrition that is being provided.

Nutritional insulin will not be given if the patient is not receiving any nutrition, in which case basal insulin and correction‐dose insulin will usually be continued. Table 2 shows the preferred insulin regimens for a variety of different nutritional circumstances, as put forth by the Society of Hospital Medicine (SHM) Glycemic Control Task Force.5

For Ms. X, the first step is to determine a TDD estimate. This patient weighs 100 kg, and is obese. Therefore, a TDD of 0.5 units/kg (50 units) is appropriate. This dose may be an underestimate of her insulin needs, but it is a conservative, reasonable starting point. The patient's basal insulin could be provided by giving one‐half of the TDD as basal insulin, such as glargine, 25 units daily. In this case, the patient will be eating dinner soon, but then will be NPO after midnight for surgery. Appropriate nutritional insulin could be provided by giving one‐third of her total nutritional insulin before this meal as a rapid‐acting insulin analog (25 units nutritional insulin per day divided by 3 meals results in a dose of 8 units per meal). After she eats dinner, additional nutritional insulin will not be given until she resumes her diet postoperatively. While NPO, her basal insulin should be continued, and her blood glucose should be checked every 4‐6 hours. An appropriate correction‐dose insulin scale should be chosen to provide a supplemental insulin dose with each bedside test of the blood glucose level, if and only if, hyperglycemia is present.

Case continued: The patient is given 8 units of lispro insulin before her dinner, and is also given a dose of 25 units of glargine insulin. She is held NPO after midnight and dextrose‐containing fluid is provided intravenously overnight at a maintenance rate. In the morning her blood glucose is 161 mg/dL before surgery. Surgery goes well, and at lunch her blood glucose is 179 mg/dL, and she is given a food tray. However, the patient says that she feels mildly nauseated, and is not sure that she will be able to eat her lunch. How should her nutritional insulin be managed in this situation?

MATCHING NUTRITION AND NUTRITIONAL INSULIN: A DIFFICULT CHALLENGE

It is the provision of the correct type and amount of nutritional insulin at the right time that is most challenging in the hospital. In the hospital, a patient's nutritional intake is often interrupted. Patients might be made NPO as part of the treatment plan, or may not be able to take nutrition by mouth because of specific medical conditions. In some cases, enteral or parenteral feeding is used to replace or enhance oral feeding. Even when alternate routes of nutrition are employed, sudden interruptions in nutrition still remain common (eg, the feeding tube falls out). Ultimately, to provide the best possible care to a diabetes patient, the nutritional insulin that is delivered must match the actual nutritional delivery (Table 2). Ideally, each institution should choose a preferred, standardized approach for each nutritional situation.

Even if institutions standardize their approach to nutritional insulin delivery in general, clinicians must be able to accurately respond to the unplanned variations in nutrition that occur in the hospital. One example of this is the patient who is expected to eat meals, but who becomes suddenly unable to do so, such as in the case above. In cases like this, the best approach is to hold the patient's nutritional insulin and allow the patient to attempt to eat the provided meal. Then, a rapid‐acting insulin analog can be given just after the meal, in proportion to the amount of the meal that was eaten. If the patient really is unable to tolerate any of the meal, then no nutritional insulin is provided. If the patient does tolerate a portion of the meal (eg, 50% of the meal is consumed), then a corresponding amount of insulin is given (eg, 50% of the scheduled nutritional insulin is given). The quick onset of the rapid‐acting insulin analogs allows near‐physiologic effect, even when they are given after the meal.

Ms. X should be allowed to eat as much of the meal as she can tolerate. Afterward, her intake can be assessed, and insulin can be provided in proportion to the amount of the meal that was eaten, as described above.

TYPE 1 DIABETES

Because type 2 diabetes is more prevalent than type 1 diabetes, hospitalists will manage this form of diabetes most often. However, it is crucial that hospitalists are also able to manage type 1 diabetes in the hospital. For the most part, the principles presented in this article apply to all types of diabetes patients. This section outlines some special considerations to remember when caring for type 1 diabetes patients in the hospital that will assure prevention of diabetic ketoacidosis in patients with type 1 diabetes.

Type 1 diabetes patients completely lack endogenous insulin production. Therefore, these patients require exogenous insulin to be provided at all times. Type 1 diabetes patients need to be provided continuous, exogenous basal insulin, even when fasting, to suppress gluconeogenesis and ketone production. Failure to provide basal insulin to a type 1 diabetes patient can lead to the rapid development (in hours) of ketoacidosis. When receiving nutrition, the patient with type 1 diabetes must also be provided with nutritional insulin to control postprandial BGs. Whereas many type 2 diabetes patients may produce sufficient endogenous insulin to meet basal requirements when fasting (ie, they produce enough basal insulin to maintain metabolic stability when they are not taking in nutrition), this is never the case for type 1 diabetes patients.

In addition, type 1 diabetes patients typically exhibit less insulin resistance than type 2 diabetes patients, especially if they are not obese. Therefore, type 1 diabetes patients often have TDDs of insulin that are lower than those of type 2 patients. This is reflected in the recommendations in Figure 5, with the TDD of insulin estimate for a lean type 1 diabetes patient of 0.3 units/kg/day.

CONTINUOUS SUBCUTANEOUS INSULIN INFUSIONS (INSULIN PUMPS) IN THE HOSPITAL

Continuous subcutaneous insulin infusion therapy (CSII), often referred to as insulin pump therapy, involves the use of a pump to provide a continuous flow of subcutaneous basal insulin (usually a rapid‐acting analog) through a needle that is left in place. This basal rate is adjustable, and therefore can be customized to meet variable needs over a 24‐hour period. When the patient takes in nutrition, a bolus of the same insulin is given, via the pump, at a dose that is appropriate to cover the nutritional intake. The advantages of CSII therapy are the capacity for precision and flexibility of the basal insulin delivery (compared to the use of a once‐daily or twice‐daily dose of long‐acting insulin analog), and the lack of a need to inject insulin boluses (which are delivered via the pump). This type of therapy is preferred by some diabetes patients, and although it is not highly prevalent in most areas, it is common enough that hospitalists must have a plan for managing it in their practices.

There are many barriers to the use of CSII in the hospital. Most of these barriers are related to the need for constant management of the pump. Most hospitalists and nurses do not have the expertise to manage this therapy in the hospital. Although the patient (or caregiver) might have the expertise to manage the pump, this is an acceptable option only if the patient is competent to manage the pump. Patient competence to use the pump must be formally assessed and documented, and the patient must agree to perform the many components of care related to managing the pump (eg, documenting the basal rate and boluses given, documenting BGs, providing tubing and other supplies).

Many hospitals currently choose a policy of converting insulin pump therapy to standard subcutaneous insulin treatment for most hospitalized patients. Usually the conversion of CSII to a physiologic subcutaneous insulin regimen (as detailed in this article) is fairly straightforwardthe basal insulin will be given as long‐acting, low‐peaking insulin, and nutritional and correction‐dose insulin can then be added as a rapid‐acting analog, in accord with the patient's needs.

Hospitals that admit a large number of insulin pump patients, or those that choose to use pumps routinely in the hospital, should create a formal policy for pump use.11 It has been suggested that the policy should assure that there is formal assessment of the patient's competence to manage the pump, that there is professional oversight of the pump management (usually via endocrinology and diabetes educator consultation), that contraindications for CSII use are clearly stated, and that there is a formal mechanism for engaging the patient and informing him of his roles and responsibilities (eg, a written agreement). The clinician must write insulin orders in the medical record that specify the basal and bolus insulin doses which are being used. Pump use may be limited to floors where nurses receive at least basic education in the principles of CSII pumps.

CARE TRANSITIONS IN THE HOSPITAL

CONCLUSIONS

Understanding the basic principles of the physiologic (basal, nutritional, and correction‐dose) insulin regimen will allow clinicians to formulate safe and effective insulin regimens in virtually any clinical situation. Simple steps can allow safe estimates of initial doses and titration toward glycemic goals. Additional information and case studies can be found in a Society of Hospital Medicine Task Force Educational Module,5 available online.

Additional resources for improving glycemic control in hospital patients are available online at the Glycemic Control Resource Room (http://www.hospitalmedicine.org/ResourceRoomRedesign/ GlycemicControl.cfm).

Recently, there has been a heightened interest in improving the quality and safety of the management of diabetes and hyperglycemia in the hospital.1 While observational data strongly suggests an association of hyperglycemia with morbidity and mortality in adults on general medicine and surgery units, clinical research has not yet defined the best practices for managing hyperglycemia in the hospital outside the intensive care unit (ICU). As a result, many physicians do not have a well‐formulated approach to managing hyperglycemia in the noncritically ill hospital patient, and the use of insulin therapy to attain targeted blood glucose (BG) control is often subject to practice variability, leading to suboptimal glycemic outcomes.

Practical guidelines for the management of this common clinical problem have been formulated by experts in the field, based on understanding of the physiology of glucose and insulin dynamics, the characteristics of currently available insulin preparations, and clinical experience. In 2004, in Clement et al.,2 the American Diabetes Association published a technical review promoting the use of physiologic (basal‐nutritional‐correction dose) insulin regimens in the hospital to achieve targeted glycemic outcomes. This approach has been disseminated via review articles,3 and more recently, a randomized, controlled trial demonstrated that hospitalized type 2 diabetes patients experienced better glycemic control when treated with a physiologic insulin regimen than when treated with sliding‐scale insulin alone.4 The Society of Hospital Medicine has assembled a Glycemic Control Task Force, which is charged with providing physicians and hospitals with practical tools to improve the safety and efficacy of diabetes management in the hospital. One product of this work is an educational module that serves as a tutorial on the best practice for the management of diabetes and hyperglycemia in the noncritically ill hospital patient.5 This article is based on that module, and provides a practical summary of the key concepts that will allow clinicians to confidently employ physiologic insulin regimens when caring for their hospital patients.

Case: Ms. X is a 56‐year‐old obese woman with type 2 diabetes mellitus who is admitted for treatment of an infected diabetes‐related foot ulcer. The patient will be allowed to eat dinner in a couple of hours, but the surgeons have requested that she be kept nothing by mouth (NPO) after midnight for surgical debridement in the morning. Her current weight is 100 kg, and her recent glycemic control can be summarized as having BG values that are usually in the mid‐200s (mg/dL) and a recent glycosylated hemoglobin (HbA1C) measurement of 10.9%. Her home medical regimen includes glipizide 10 mg daily, metformin 1000 mg twice daily, and 20 units of neutral protamine hagadorn (NPH) insulin at bedtime. Her blood glucose in the Emergency Department is 289 mg/dL. How should this patient's blood glucose be managed in the hospital?

PHARMACOLOGIC CONTROL OF BG IN THE HOSPITAL: INSULIN IS THE ANTIHYPERGLYCEMIC AGENT OF CHOICE

Although oral antihyperglycemic agents are frequently used in the outpatient setting, there are many potential disadvantages to using these medications in acutely ill hospital patients, as shown in Figure 1.2, 3 Oral antihyperglycemic agents, in general, are difficult to quickly titrate to effect, and have side effects that can limit their use in the hospital. Metformin can lead to lactic acidosis when it is used in clinical situations that predispose to lactate production (eg, renal failure, circulatory failure, hypoxemia). Therefore, metformin should be held in patients who have, or are at risk for, these conditions, each of which may be encountered in the hospital. Also, agents that stimulate the release of insulin, such as sulfonylureas, should be held in patients with variable nutritional intake, to prevent hypoglycemia. In contrast, insulin acts rapidly, responds in a timely fashion to dose titrations, and can be used effectively in virtually all patients and clinical situations to control BG levels. This makes insulin the treatment of choice for hyperglycemia in the hospital. Insulin can be administered via subcutaneous doses or as an intravenous infusion for cases in which rapid titration is the goal. Intravenous insulin infusions are the preferred mode of insulin delivery in the ICU setting, and may be appropriate for some noncritically ill patients in hospitals that have developed systems to safely provide them on general wards. Subcutaneous insulin is most commonly used in the noncritically ill patient population and is the focus of this article.

Figure 1

Although insulin is the drug of choice for managing hyperglycemia in the hospital, there are some situations when it is appropriate to continue oral antihyperglycemic medications in the hospital. These agents may be continued in hospitalized patients who are clinically stable, and who have normal nutritional intake, normal BG levels, and stable renal and cardiac function. They may also be started or resumed in the hospital if they are to be included in the discharge medication regimen once the patient is clinically stable and if it has been assured that contraindications to their use no longer exist.

Ms. X should be treated with a more robust (physiologic) insulin regimen. This statement would be true, even if she were not an inpatient with a foot infection. Her glycemic control is currently poor, as evidenced by her high HbA1C and her elevated admission BG, and is unlikely to be appreciably improved with the addition of any pharmacologic agent other than insulin. The glipizide should be held, as the patient will be NPO after midnight. Most experts would recommend holding the metformin at this time as well, since the patient will be undergoing a surgical procedure in the morning that places her at risk for predisposing factors to lactic acidosis.

INPATIENT GLYCEMIC TARGETS

At present, recommended glycemic targets for noncritically ill hospital patients are based entirely on expert opinion, as there have been no clinical studies directly comparing different glycemic targets in this patient population. However, the American College of Endocrinology, the American Association of Clinical Endocrinologists, and the American Diabetes Association do provide recommendations about glycemic targets for inpatients (Table 1).6, 7 Although controversial, these recommendations make it clear that uncontrolled hyperglycemia is no longer the accepted standard of care for hospitalized patients, and illustrate the consensus of expert opinion on the subject. Of note, many hospitals are adopting glycemic targets that are less stringent than those shown in Table 1, recognizing the challenges of controlling BG levels in hospitalized patients, and the potential risk for hypoglycemia when lower BG targets are used. Each hospital's glycemic control champions must reach consensus on a target BG range for their institution. In practice this range has been 90110 mg/dL for the lower BG limit and 140180 mg/dL for the upper BG limit. It is also important to note that the recommendations from professional organizations emphasize the need to individualize BG targets, based on the clinical circumstances of each patient.

Ms. X is exhibiting glycemic values far outside of the recommended upper limit of 180 mg/dL, and treatment with insulin monotherapy is the most appropriate strategy in this case.

PHYSIOLOGIC (BASAL‐BOLUS, PLUS CORRECTION DOSE) INSULIN

The management of hyperglycemia and diabetes in the inpatient setting is challenging due to the many changes that patients experience in the hospital. Hospitalized patients often experience changes in their nutritional intake and their medication regimen. In addition, hospitalized patients usually experience the stress of acute illness and are treated with medications that might impact glycemic control. Figure 2 lists some of the barriers to achieving glycemic control in hospitalized patients. The inpatient insulin program needs to be flexible enough to allow for maintenance of glycemic control in the face of tumultuous circumstances. This can best be accomplished by the use of a physiologic insulin program. This means using exogenous insulin to mimic normal physiologic insulin activity by providing the correct types and doses of insulin at the correct times.

Figure 2

A physiologic insulin regimen can be conceptualized as having 3 separate components: basal insulin, nutritional (or prandial/meal) insulin, and correction dose (or supplemental) insulin.2 A patient's total daily dose (TDD) of insulin is the sum of all of these, and represents the amount of insulin that a patient requires over the course of 1 day while receiving adequate nutrition. Basal insulin is the insulin normally released continuously by the pancreas, even when fasting. This serves to suppress glucose and ketone production. When nutrition is ingested, there is a surge in the level of glucose in the blood, and this surge is accompanied by rapid secretion of additional insulin to allow for the appropriate utilization of the glucose. The insulin that is secreted in response to nutritional intake is referred to as nutritional insulin. About one‐half of the total daily insulin secreted by a healthy normal human serves a basal function, and about one‐half is secreted in response to nutritional intake.8 Understanding this bit of physiology (the 50/50 rule) is very helpful for creating flexible regimens using exogenous insulin. Although the 50/50 rule is useful in many circumstances, there are some notable exceptions. In some cases, basal insulin might be expected to be less than one‐half of the TDD (eg, enteral feeds, as discussed below). Additional correction dose insulin is given to correct hyperglycemia that occurs despite scheduled doses of basal and nutritional insulin.

It is an important practical consideration to note that when a person with diabetes is acutely ill or stressed, as is commonly the case in the hospital setting, total daily insulin requirements increase. This is due to the action of insulin counterregulatory hormones such as catecholamines, cortisol, growth hormone, and glucagon. The hospitalized patient is therefore likely to require a TDD that is higher than that required when well. This is particularly true for the basal insulin dose. Conversely, insulin requirements will decrease as a patient recovers from acute illness, and it may be necessary to lower insulin doses as BG levels decrease during convalescence.

Exogenous basal insulin is provided as a long‐acting or intermediate‐acting, low‐peaking or nonpeaking insulin (eg, glargine or detemir), that allows for a consistent level of basal insulin (Figure 3). This insulin is provided even when the person is not receiving any nutrition. Although twice daily NPH insulin can be used to provide basal insulin, the peak (as shown in Figure 3) is likely to exceed the level of insulin that is truly required for basal needs, which can result in hypoglycemia. In theory, NPH insulin would be less physiologic than glargine or detemir, although no studies have compared these insulins in the hospital setting. When using NPH insulin as a basal insulin in a patient who is designated NPO, the dose should be reduced by one‐third to one‐half to avoid hypoglycemia that may occur when it peaks.2

Figure 3

Exogenous nutritional insulin must be provided in a way that matches the nutrition that is being provided to the patient. For example, a patient who is receiving nutritional boluses (ie, meals or bolus tube feeds) can be given rapid‐acting insulin (eg, aspart, glulisine, lispro) along with each nutritional bolus to cover the glycemic peak that is caused by the meal. The rapid‐acting analog insulins can also be given at the end of a meal or bolus tube feed for cases in which it is not clear if the nutrition will be well tolerated. A reduction in the insulin dose proportionate to the amount of nutrition actually taken can then be made to decrease the risk of subsequent hypoglycemia. Regular insulin can also be given in anticipation of a meal or tube feed, but its later peak (as shown in Figure 3) requires that it be given 30 minutes before a meal is ingested, the timing of which is a challenge on most nursing units. Patients who are not receiving any nutrition should not receive nutritional insulin. And, patients receiving alternative forms of nutrition will require different nutritional insulin regimens to adequately cover their nutritional glycemic loads, as discussed below.

The separate provision of basal and nutritional insulin results in a highly‐flexible insulin program that can provide basal insulin to patients even when they are not receiving significant nutrition, and can be easily adjusted to provide appropriate nutritional insulin to match actual nutritional delivery.

Correction‐dose insulin is the small amount of insulin that is given to patients, in addition to basal and nutritional insulin, to correct hyperglycemia. Correction‐dose insulin is usually provided as rapid‐acting or regular insulin (usually the same type as the nutritional insulin), and is given in a dose that is specifically designed to reduce the patient's BG back into the target range. It is usually given at the same time as the nutritional insulin in patients who are receiving nutrition (or every 4 to 6 hours in patients who are not). Correction‐dose insulin is often written in a stepped format, to provide the appropriate amount of insulin for a given BG value. It differs from the traditional sliding‐scale in that it is not used alone (but rather as 1 component of a physiologic program), and in that it is customized to match the insulin sensitivity for each patient. Most standardized order sets for subcutaneous insulin provide several different correction‐dose scales to choose from, depending on the patient's weight or total daily insulin requirement.

If correction‐dose insulin is required consistently, or in high doses, it suggests a need to modify the basal and/or nutritional insulin. A proportion of the total number of units of correction‐dose insulin given in the preceding 24 hours can be distributed into basal and nutritional insulin doses for the next day if there is ongoing need for significant correction‐doses of insulin. A well‐designed, physiologic insulin regimen should provide targeted glycemic control, without a need for constantly adding large correctional boluses.

Some insulins do not fit neatly into either basal or nutritional insulin categories. For example, mixed insulins (eg, 70/30, rapid‐analog/NPH mixtures) combine basal and nutritional insulins to form either a double‐peaking insulin or an intermediate‐peaking insulin. The use of this type of insulin makes it impossible to manipulate the basal and nutritional components separately to enable attainment of BG targets. Therefore, the role of this type of insulin is limited in the hospital setting. Mixed insulins may, however, be started once the patient is clinically stable if they will be part of the discharge regimen.

Diabetes and hyperglycemia in the hospitalized patient require active management, and there are no autopilot insulin regimens. The use of sliding scale insulin alone to manage hyperglycemia is a common practice in hospitals.9 However, this is an historic practice that is based on the erroneous idea that BG can be managed with a reactive strategy. When sliding‐scale insulin is used as the sole modality of insulin therapy, insulin is provided only after metabolic control has been lost, and usually does not provide an appropriate dose of insulin, considering basal, nutritional, and correctional needs. The end result is poor glycemic control.9, 10 A recent randomized, controlled trial demonstrated that a physiologic insulin regimen is indeed superior to a standardized insulin sliding‐scale for managing inpatient hyperglycemia.4

Ms. X should be given an insulin regimen that includes basal, nutritional, and correctional components. The provision of separate basal and nutritional insulin will allow the clinicians to provide the patient with basal insulin even when her nutritional insulin is held, and to easily modify her nutritional insulin, depending on her nutritional intake.

PHYSIOLOGIC INSULIN: A PRACTICAL APPROACH

The use of physiologic insulin in the hospital can be facilitated by considering a stepwise approach (Figure 4).5 The first step is to estimate the amount of insulin that the patient will require over the course of a day if taking adequate nutrition (this is the TDD). If the patient has been treated with subcutaneous insulin before being admitted to the hospital, the clinician can use the outpatient TDD to gauge the insulin needs. To do this, the clinician simply adds up the total number of units of insulin that a patient takes at home in a day. Using this method to estimate the patient's TDD can be very helpful, even if the clinician plans to use different types of insulin while the patient is hospitalized. When using this approach, one should consider the patient's prior metabolic control on the existing regimen (ie, if the patient's glycemic control was poor on the preexisting regimen, an increase in the TDD would be necessary). In addition, clinicians should recognize that insulin requirements usually increase when patients are acutely ill, as discussed above. Managing diabetes and hyperglycemia in the hospital is very different than doing so in the outpatient arena, and hospitalists should not feel bound by the outpatient regimen.

Figure 4

In addition, a weight‐based estimation of the TDD can be very helpful in determining a starting dose of insulin in a hospitalized patient (see Figure 5). An estimate of 0.4 units/kg of body weight provides a conservative starting point for the TDD for most patients. Occasionally, a lower starting dose of 0.3 units/kg of body weight might be safer for those patients who are likely to be very sensitive to insulin, or who are otherwise at increased at risk for hypoglycemia (see Figure 5). Patients who are overweight or obese often require considerably higher TDDs in the range of 0.5‐0.6 (or even more) units/kg of body weight. Some may require over 1 unit/kg of body weight for their TDD. Therefore, the doses provided by these calculations represent conservative estimates in most patients. Hospitalists should be able to confidently make these dose estimates and avoid dependence on nonphysiologic regimens such as sliding‐scale insulin alone.

Figure 5

The presence of risk factors for hypoglycemia or hyperglycemia should temper the dose calculations. Clinical conditions associated with hyperglycemia include obesity, certain medications (eg, glucocorticoids, catecholamines, tacrolimus, cyclosporine), and changes in nutritional intake (Figure 2). Clinical conditions associated with hypoglycemia are summarized in Figure 6. It is important to recognize that these calculations are intended to give the clinician a safe and rational starting point for insulin dosing. More important than the calculations is the careful monitoring of BG levels and timely modifications of the insulin regimen that follow.

Figure 6

The second step in developing a physiologic insulin regimen is to determine the patient's nutritional regimen. The third step, then, is to decide how the TDD will be distributed into basal and nutritional insulins, and which insulin will be used for each. As noted above, for most patients, approximately one‐half of the TDD will be provided as basal insulin, and the other one‐half given as nutritional insulin. When patients are receiving nutrition, the insulin must be given in a way that matches the timing of nutrition delivery (eg, with each meal or bolus tube feeding), and provides appropriate insulin coverage for the nutrition that is being provided.

Nutritional insulin will not be given if the patient is not receiving any nutrition, in which case basal insulin and correction‐dose insulin will usually be continued. Table 2 shows the preferred insulin regimens for a variety of different nutritional circumstances, as put forth by the Society of Hospital Medicine (SHM) Glycemic Control Task Force.5

For Ms. X, the first step is to determine a TDD estimate. This patient weighs 100 kg, and is obese. Therefore, a TDD of 0.5 units/kg (50 units) is appropriate. This dose may be an underestimate of her insulin needs, but it is a conservative, reasonable starting point. The patient's basal insulin could be provided by giving one‐half of the TDD as basal insulin, such as glargine, 25 units daily. In this case, the patient will be eating dinner soon, but then will be NPO after midnight for surgery. Appropriate nutritional insulin could be provided by giving one‐third of her total nutritional insulin before this meal as a rapid‐acting insulin analog (25 units nutritional insulin per day divided by 3 meals results in a dose of 8 units per meal). After she eats dinner, additional nutritional insulin will not be given until she resumes her diet postoperatively. While NPO, her basal insulin should be continued, and her blood glucose should be checked every 4‐6 hours. An appropriate correction‐dose insulin scale should be chosen to provide a supplemental insulin dose with each bedside test of the blood glucose level, if and only if, hyperglycemia is present.

Case continued: The patient is given 8 units of lispro insulin before her dinner, and is also given a dose of 25 units of glargine insulin. She is held NPO after midnight and dextrose‐containing fluid is provided intravenously overnight at a maintenance rate. In the morning her blood glucose is 161 mg/dL before surgery. Surgery goes well, and at lunch her blood glucose is 179 mg/dL, and she is given a food tray. However, the patient says that she feels mildly nauseated, and is not sure that she will be able to eat her lunch. How should her nutritional insulin be managed in this situation?

MATCHING NUTRITION AND NUTRITIONAL INSULIN: A DIFFICULT CHALLENGE

It is the provision of the correct type and amount of nutritional insulin at the right time that is most challenging in the hospital. In the hospital, a patient's nutritional intake is often interrupted. Patients might be made NPO as part of the treatment plan, or may not be able to take nutrition by mouth because of specific medical conditions. In some cases, enteral or parenteral feeding is used to replace or enhance oral feeding. Even when alternate routes of nutrition are employed, sudden interruptions in nutrition still remain common (eg, the feeding tube falls out). Ultimately, to provide the best possible care to a diabetes patient, the nutritional insulin that is delivered must match the actual nutritional delivery (Table 2). Ideally, each institution should choose a preferred, standardized approach for each nutritional situation.

Even if institutions standardize their approach to nutritional insulin delivery in general, clinicians must be able to accurately respond to the unplanned variations in nutrition that occur in the hospital. One example of this is the patient who is expected to eat meals, but who becomes suddenly unable to do so, such as in the case above. In cases like this, the best approach is to hold the patient's nutritional insulin and allow the patient to attempt to eat the provided meal. Then, a rapid‐acting insulin analog can be given just after the meal, in proportion to the amount of the meal that was eaten. If the patient really is unable to tolerate any of the meal, then no nutritional insulin is provided. If the patient does tolerate a portion of the meal (eg, 50% of the meal is consumed), then a corresponding amount of insulin is given (eg, 50% of the scheduled nutritional insulin is given). The quick onset of the rapid‐acting insulin analogs allows near‐physiologic effect, even when they are given after the meal.

Ms. X should be allowed to eat as much of the meal as she can tolerate. Afterward, her intake can be assessed, and insulin can be provided in proportion to the amount of the meal that was eaten, as described above.

TYPE 1 DIABETES

Because type 2 diabetes is more prevalent than type 1 diabetes, hospitalists will manage this form of diabetes most often. However, it is crucial that hospitalists are also able to manage type 1 diabetes in the hospital. For the most part, the principles presented in this article apply to all types of diabetes patients. This section outlines some special considerations to remember when caring for type 1 diabetes patients in the hospital that will assure prevention of diabetic ketoacidosis in patients with type 1 diabetes.

Type 1 diabetes patients completely lack endogenous insulin production. Therefore, these patients require exogenous insulin to be provided at all times. Type 1 diabetes patients need to be provided continuous, exogenous basal insulin, even when fasting, to suppress gluconeogenesis and ketone production. Failure to provide basal insulin to a type 1 diabetes patient can lead to the rapid development (in hours) of ketoacidosis. When receiving nutrition, the patient with type 1 diabetes must also be provided with nutritional insulin to control postprandial BGs. Whereas many type 2 diabetes patients may produce sufficient endogenous insulin to meet basal requirements when fasting (ie, they produce enough basal insulin to maintain metabolic stability when they are not taking in nutrition), this is never the case for type 1 diabetes patients.

In addition, type 1 diabetes patients typically exhibit less insulin resistance than type 2 diabetes patients, especially if they are not obese. Therefore, type 1 diabetes patients often have TDDs of insulin that are lower than those of type 2 patients. This is reflected in the recommendations in Figure 5, with the TDD of insulin estimate for a lean type 1 diabetes patient of 0.3 units/kg/day.

CONTINUOUS SUBCUTANEOUS INSULIN INFUSIONS (INSULIN PUMPS) IN THE HOSPITAL

Continuous subcutaneous insulin infusion therapy (CSII), often referred to as insulin pump therapy, involves the use of a pump to provide a continuous flow of subcutaneous basal insulin (usually a rapid‐acting analog) through a needle that is left in place. This basal rate is adjustable, and therefore can be customized to meet variable needs over a 24‐hour period. When the patient takes in nutrition, a bolus of the same insulin is given, via the pump, at a dose that is appropriate to cover the nutritional intake. The advantages of CSII therapy are the capacity for precision and flexibility of the basal insulin delivery (compared to the use of a once‐daily or twice‐daily dose of long‐acting insulin analog), and the lack of a need to inject insulin boluses (which are delivered via the pump). This type of therapy is preferred by some diabetes patients, and although it is not highly prevalent in most areas, it is common enough that hospitalists must have a plan for managing it in their practices.

There are many barriers to the use of CSII in the hospital. Most of these barriers are related to the need for constant management of the pump. Most hospitalists and nurses do not have the expertise to manage this therapy in the hospital. Although the patient (or caregiver) might have the expertise to manage the pump, this is an acceptable option only if the patient is competent to manage the pump. Patient competence to use the pump must be formally assessed and documented, and the patient must agree to perform the many components of care related to managing the pump (eg, documenting the basal rate and boluses given, documenting BGs, providing tubing and other supplies).

Many hospitals currently choose a policy of converting insulin pump therapy to standard subcutaneous insulin treatment for most hospitalized patients. Usually the conversion of CSII to a physiologic subcutaneous insulin regimen (as detailed in this article) is fairly straightforwardthe basal insulin will be given as long‐acting, low‐peaking insulin, and nutritional and correction‐dose insulin can then be added as a rapid‐acting analog, in accord with the patient's needs.

Hospitals that admit a large number of insulin pump patients, or those that choose to use pumps routinely in the hospital, should create a formal policy for pump use.11 It has been suggested that the policy should assure that there is formal assessment of the patient's competence to manage the pump, that there is professional oversight of the pump management (usually via endocrinology and diabetes educator consultation), that contraindications for CSII use are clearly stated, and that there is a formal mechanism for engaging the patient and informing him of his roles and responsibilities (eg, a written agreement). The clinician must write insulin orders in the medical record that specify the basal and bolus insulin doses which are being used. Pump use may be limited to floors where nurses receive at least basic education in the principles of CSII pumps.

CARE TRANSITIONS IN THE HOSPITAL

CONCLUSIONS

Understanding the basic principles of the physiologic (basal, nutritional, and correction‐dose) insulin regimen will allow clinicians to formulate safe and effective insulin regimens in virtually any clinical situation. Simple steps can allow safe estimates of initial doses and titration toward glycemic goals. Additional information and case studies can be found in a Society of Hospital Medicine Task Force Educational Module,5 available online.

Additional resources for improving glycemic control in hospital patients are available online at the Glycemic Control Resource Room (http://www.hospitalmedicine.org/ResourceRoomRedesign/ GlycemicControl.cfm).

The delayed and variable absorption of subcutaneous (SC) insulin has always provided challenges for the rapid and predictable control of hyperglycemia in the acute care setting. Conversely, intravenous infusion of human regular insulin provides a continuous and essentially immediate delivery mechanism. Once in the circulation, insulin has a very short half‐life of about 5 to 7 minutes and a biological effect of about 20 minutes.1 Intravenous insulin infusions are well‐established in several acute care settings including hyperglycemic emergencies, perioperative glucose management, and glucose control during labor and delivery.2, 3

The beneficial effects seen in early trials of strict glycemic control involving intensive care unit (ICU) patients47 (particularly cardiac surgery patients) and guidelines for inpatient glycemic control8 stimulated widespread interest in adopting insulin infusion protocols (IIPs) focused on achieving strict glycemic targets. The initial enthusiasm has been tempered by uneven results in trials of tight glycemic control, concerns about the effects of excessive hypoglycemia, and the resources needed to implement and maintain an IIP.9 Although considerable controversy about the ideal glycemic target for different patient populations exists, and will likely continue for some time, this article is not a review of the evidence for supporting 1 glycemic target versus another. Regardless of the glycemic target chosen, a standardized algorithm and accompanying program of monitoring are widely endorsed for both safety and quality reasons.1014 Most medical centers are at least attempting to implement nurse‐driven protocols that have demonstrated better perfomance than SC regimens15 and physician‐driven insulin infusions.16, 17 In this article, we outline several variables in IIP design and implementation and endorse several aspects of design and implementation that will likely result in improved staff acceptance and, ultimately, a more safe and effective IIP.

PREPARING TO IMPLEMENT AN IIP

CHOOSING AN IIP FOR YOUR HOSPITAL

See Table 2 for a comparison of several features identified in selected published protocols.7, 2127 This is not a comprehensive list of all protocols found in the literature. Rather, the authors consider it representative of the various types of IIPs or best recognized IIPs in the literature. Note that there is variability in study population, the glucose targets, hypoglycemia, the time to reach the target, and the time spent in the target range. Other practical factors to consider in reviewing the literature and selecting an IIP design are the complexity of the protocol, the required process steps or calculations, the evidence for staff acceptance, and the level of resources supporting the published protocol.

ENHANCING THE DESIGN OF YOUR IIP

Once the improvement team has identified and examined current order sets and protocols in the context of the literature, we encourage consolidation of institutional insulin infusion orders into a common basic structure. This basic structure should be enhanced by incorporating a variety of elements designed to enhance the reliability of use and safety of the IIP. These design features are outlined in Table 3. Randomized trial evidence of the effectiveness of these design features are largely lacking, but they are well grounded in reliability principles and common experience, and have also been recommended by others.1013, 58

The orders should require a single physician signature and limited physician choices as the vehicle initiating the nurse‐driven protocol. The glycemic target range should be explicitly identified, and guidance for calling the physician and how to handle interruptions in nutrition should be embedded in the order set. Frequent monitoring of glucose levels is necessary for the safe infusion of insulin. Guidance for how often the monitoring is required must be explicit and included in the infusion order set, and standardization of documentation of the infusion rates and glucose values is highly desirable. IIPs that adjust based on the velocity of glucose change and insulin sensitivity are desirable. Certain elements may be more appropriate for some institutions than others, partly based on previous protocols and methods of practice. For example, the hypoglycemia protocol may be embedded or referred to as a separate standard of care with clear presence in the chart. The intended timing of conversion from IV to SC insulin should be included, but the actual method may be the subject of a separate order set. At other times, the conversion formula will be part of the initial intravenous order set.

IMPLEMENTATION: ADDRESSING SAFETY ISSUES

The use of insulin infusions comes with several potential hazards. Many of these potential complications can be proactively addressed, thereby minimizing accidental injuries to the patient on an insulin infusion.

IMPLEMENTATION: EDUCATING AND ENGAGING NURSING AND PHYSICIAN STAFF

Nursing staff generally bear the brunt of the burden on the front line of implementing intensive IIPs. Educational efforts for nurses should include the rationale for intensive insulin therapy and use of an IIP. Additionally, detailed, case‐based instruction on utilization of the IIP is required. Properly educated, nursing staff often become the strongest advocates of the IIP. In addition, they can frequently provide important input when situations arise that require troubleshooting. Regular feedback sessions early in implementation that address ease of use, clarity of orders, and difficulties encountered by nurses can be invaluable. Improvement teams need to provide frequent in‐service training and updates on the IIP selected after implementation. This is imperative to promote nursing acceptance and adherence to the IIP chosen, particularly with consideration for traveling nurses. The importance of nursing champions to design and carry out this work cannot be overstated. Educational programs focusing on the physician staff can also be very useful, particularly when focused on high‐volume physicians and influential thought leaders.

IMPLEMENTATION: ADDRESSING COMMON CLINICAL SITUATIONS

ASSESSING THE IMPACT OF YOUR EFFORTS: FOLLOW‐UP AND FOLLOW‐THROUGH

CONCLUSIONS

Insulin infusions are a powerful clinical tool in the inpatient setting to maintain glycemic control. Many IIPs have been developed and used successfully. The institutional challenge is to select, modify, and implement the IIP to reduce hyperglycemia and improve outcomes without excess hypoglycemia. In order to accomplish this goal safely and efficiently, standardized processes and collaboration between physicians, nurses, and pharmacists are needed. The keys to minimizing errors include developing a culture of safety and cooperation, back‐up checks, standardization, automation, and robust training for all those who are involved in the care of a patient on an insulin infusion. Although we encourage standardization and the use of protocols, providers always need to consider the unique clinical circumstances and potential problems presented by each individual patient. It is important to recognize the many barriers to successful implementation of an IIP, but strategies exist to overcome these. Finally, remember that the process does not end with the development phase. Continued review is paramount to success. Note variations in use, analyze them, and learn from them, in order to continually improve the process of care.

The delayed and variable absorption of subcutaneous (SC) insulin has always provided challenges for the rapid and predictable control of hyperglycemia in the acute care setting. Conversely, intravenous infusion of human regular insulin provides a continuous and essentially immediate delivery mechanism. Once in the circulation, insulin has a very short half‐life of about 5 to 7 minutes and a biological effect of about 20 minutes.1 Intravenous insulin infusions are well‐established in several acute care settings including hyperglycemic emergencies, perioperative glucose management, and glucose control during labor and delivery.2, 3

The beneficial effects seen in early trials of strict glycemic control involving intensive care unit (ICU) patients47 (particularly cardiac surgery patients) and guidelines for inpatient glycemic control8 stimulated widespread interest in adopting insulin infusion protocols (IIPs) focused on achieving strict glycemic targets. The initial enthusiasm has been tempered by uneven results in trials of tight glycemic control, concerns about the effects of excessive hypoglycemia, and the resources needed to implement and maintain an IIP.9 Although considerable controversy about the ideal glycemic target for different patient populations exists, and will likely continue for some time, this article is not a review of the evidence for supporting 1 glycemic target versus another. Regardless of the glycemic target chosen, a standardized algorithm and accompanying program of monitoring are widely endorsed for both safety and quality reasons.1014 Most medical centers are at least attempting to implement nurse‐driven protocols that have demonstrated better perfomance than SC regimens15 and physician‐driven insulin infusions.16, 17 In this article, we outline several variables in IIP design and implementation and endorse several aspects of design and implementation that will likely result in improved staff acceptance and, ultimately, a more safe and effective IIP.

PREPARING TO IMPLEMENT AN IIP

CHOOSING AN IIP FOR YOUR HOSPITAL

See Table 2 for a comparison of several features identified in selected published protocols.7, 2127 This is not a comprehensive list of all protocols found in the literature. Rather, the authors consider it representative of the various types of IIPs or best recognized IIPs in the literature. Note that there is variability in study population, the glucose targets, hypoglycemia, the time to reach the target, and the time spent in the target range. Other practical factors to consider in reviewing the literature and selecting an IIP design are the complexity of the protocol, the required process steps or calculations, the evidence for staff acceptance, and the level of resources supporting the published protocol.

ENHANCING THE DESIGN OF YOUR IIP

Once the improvement team has identified and examined current order sets and protocols in the context of the literature, we encourage consolidation of institutional insulin infusion orders into a common basic structure. This basic structure should be enhanced by incorporating a variety of elements designed to enhance the reliability of use and safety of the IIP. These design features are outlined in Table 3. Randomized trial evidence of the effectiveness of these design features are largely lacking, but they are well grounded in reliability principles and common experience, and have also been recommended by others.1013, 58

The orders should require a single physician signature and limited physician choices as the vehicle initiating the nurse‐driven protocol. The glycemic target range should be explicitly identified, and guidance for calling the physician and how to handle interruptions in nutrition should be embedded in the order set. Frequent monitoring of glucose levels is necessary for the safe infusion of insulin. Guidance for how often the monitoring is required must be explicit and included in the infusion order set, and standardization of documentation of the infusion rates and glucose values is highly desirable. IIPs that adjust based on the velocity of glucose change and insulin sensitivity are desirable. Certain elements may be more appropriate for some institutions than others, partly based on previous protocols and methods of practice. For example, the hypoglycemia protocol may be embedded or referred to as a separate standard of care with clear presence in the chart. The intended timing of conversion from IV to SC insulin should be included, but the actual method may be the subject of a separate order set. At other times, the conversion formula will be part of the initial intravenous order set.

IMPLEMENTATION: ADDRESSING SAFETY ISSUES

The use of insulin infusions comes with several potential hazards. Many of these potential complications can be proactively addressed, thereby minimizing accidental injuries to the patient on an insulin infusion.

IMPLEMENTATION: EDUCATING AND ENGAGING NURSING AND PHYSICIAN STAFF

Nursing staff generally bear the brunt of the burden on the front line of implementing intensive IIPs. Educational efforts for nurses should include the rationale for intensive insulin therapy and use of an IIP. Additionally, detailed, case‐based instruction on utilization of the IIP is required. Properly educated, nursing staff often become the strongest advocates of the IIP. In addition, they can frequently provide important input when situations arise that require troubleshooting. Regular feedback sessions early in implementation that address ease of use, clarity of orders, and difficulties encountered by nurses can be invaluable. Improvement teams need to provide frequent in‐service training and updates on the IIP selected after implementation. This is imperative to promote nursing acceptance and adherence to the IIP chosen, particularly with consideration for traveling nurses. The importance of nursing champions to design and carry out this work cannot be overstated. Educational programs focusing on the physician staff can also be very useful, particularly when focused on high‐volume physicians and influential thought leaders.

IMPLEMENTATION: ADDRESSING COMMON CLINICAL SITUATIONS

ASSESSING THE IMPACT OF YOUR EFFORTS: FOLLOW‐UP AND FOLLOW‐THROUGH

CONCLUSIONS

Insulin infusions are a powerful clinical tool in the inpatient setting to maintain glycemic control. Many IIPs have been developed and used successfully. The institutional challenge is to select, modify, and implement the IIP to reduce hyperglycemia and improve outcomes without excess hypoglycemia. In order to accomplish this goal safely and efficiently, standardized processes and collaboration between physicians, nurses, and pharmacists are needed. The keys to minimizing errors include developing a culture of safety and cooperation, back‐up checks, standardization, automation, and robust training for all those who are involved in the care of a patient on an insulin infusion. Although we encourage standardization and the use of protocols, providers always need to consider the unique clinical circumstances and potential problems presented by each individual patient. It is important to recognize the many barriers to successful implementation of an IIP, but strategies exist to overcome these. Finally, remember that the process does not end with the development phase. Continued review is paramount to success. Note variations in use, analyze them, and learn from them, in order to continually improve the process of care.

The delayed and variable absorption of subcutaneous (SC) insulin has always provided challenges for the rapid and predictable control of hyperglycemia in the acute care setting. Conversely, intravenous infusion of human regular insulin provides a continuous and essentially immediate delivery mechanism. Once in the circulation, insulin has a very short half‐life of about 5 to 7 minutes and a biological effect of about 20 minutes.1 Intravenous insulin infusions are well‐established in several acute care settings including hyperglycemic emergencies, perioperative glucose management, and glucose control during labor and delivery.2, 3

The beneficial effects seen in early trials of strict glycemic control involving intensive care unit (ICU) patients47 (particularly cardiac surgery patients) and guidelines for inpatient glycemic control8 stimulated widespread interest in adopting insulin infusion protocols (IIPs) focused on achieving strict glycemic targets. The initial enthusiasm has been tempered by uneven results in trials of tight glycemic control, concerns about the effects of excessive hypoglycemia, and the resources needed to implement and maintain an IIP.9 Although considerable controversy about the ideal glycemic target for different patient populations exists, and will likely continue for some time, this article is not a review of the evidence for supporting 1 glycemic target versus another. Regardless of the glycemic target chosen, a standardized algorithm and accompanying program of monitoring are widely endorsed for both safety and quality reasons.1014 Most medical centers are at least attempting to implement nurse‐driven protocols that have demonstrated better perfomance than SC regimens15 and physician‐driven insulin infusions.16, 17 In this article, we outline several variables in IIP design and implementation and endorse several aspects of design and implementation that will likely result in improved staff acceptance and, ultimately, a more safe and effective IIP.

PREPARING TO IMPLEMENT AN IIP

CHOOSING AN IIP FOR YOUR HOSPITAL

See Table 2 for a comparison of several features identified in selected published protocols.7, 2127 This is not a comprehensive list of all protocols found in the literature. Rather, the authors consider it representative of the various types of IIPs or best recognized IIPs in the literature. Note that there is variability in study population, the glucose targets, hypoglycemia, the time to reach the target, and the time spent in the target range. Other practical factors to consider in reviewing the literature and selecting an IIP design are the complexity of the protocol, the required process steps or calculations, the evidence for staff acceptance, and the level of resources supporting the published protocol.

ENHANCING THE DESIGN OF YOUR IIP

Once the improvement team has identified and examined current order sets and protocols in the context of the literature, we encourage consolidation of institutional insulin infusion orders into a common basic structure. This basic structure should be enhanced by incorporating a variety of elements designed to enhance the reliability of use and safety of the IIP. These design features are outlined in Table 3. Randomized trial evidence of the effectiveness of these design features are largely lacking, but they are well grounded in reliability principles and common experience, and have also been recommended by others.1013, 58

The orders should require a single physician signature and limited physician choices as the vehicle initiating the nurse‐driven protocol. The glycemic target range should be explicitly identified, and guidance for calling the physician and how to handle interruptions in nutrition should be embedded in the order set. Frequent monitoring of glucose levels is necessary for the safe infusion of insulin. Guidance for how often the monitoring is required must be explicit and included in the infusion order set, and standardization of documentation of the infusion rates and glucose values is highly desirable. IIPs that adjust based on the velocity of glucose change and insulin sensitivity are desirable. Certain elements may be more appropriate for some institutions than others, partly based on previous protocols and methods of practice. For example, the hypoglycemia protocol may be embedded or referred to as a separate standard of care with clear presence in the chart. The intended timing of conversion from IV to SC insulin should be included, but the actual method may be the subject of a separate order set. At other times, the conversion formula will be part of the initial intravenous order set.

IMPLEMENTATION: ADDRESSING SAFETY ISSUES

The use of insulin infusions comes with several potential hazards. Many of these potential complications can be proactively addressed, thereby minimizing accidental injuries to the patient on an insulin infusion.

IMPLEMENTATION: EDUCATING AND ENGAGING NURSING AND PHYSICIAN STAFF

Nursing staff generally bear the brunt of the burden on the front line of implementing intensive IIPs. Educational efforts for nurses should include the rationale for intensive insulin therapy and use of an IIP. Additionally, detailed, case‐based instruction on utilization of the IIP is required. Properly educated, nursing staff often become the strongest advocates of the IIP. In addition, they can frequently provide important input when situations arise that require troubleshooting. Regular feedback sessions early in implementation that address ease of use, clarity of orders, and difficulties encountered by nurses can be invaluable. Improvement teams need to provide frequent in‐service training and updates on the IIP selected after implementation. This is imperative to promote nursing acceptance and adherence to the IIP chosen, particularly with consideration for traveling nurses. The importance of nursing champions to design and carry out this work cannot be overstated. Educational programs focusing on the physician staff can also be very useful, particularly when focused on high‐volume physicians and influential thought leaders.

IMPLEMENTATION: ADDRESSING COMMON CLINICAL SITUATIONS

ASSESSING THE IMPACT OF YOUR EFFORTS: FOLLOW‐UP AND FOLLOW‐THROUGH

CONCLUSIONS

Insulin infusions are a powerful clinical tool in the inpatient setting to maintain glycemic control. Many IIPs have been developed and used successfully. The institutional challenge is to select, modify, and implement the IIP to reduce hyperglycemia and improve outcomes without excess hypoglycemia. In order to accomplish this goal safely and efficiently, standardized processes and collaboration between physicians, nurses, and pharmacists are needed. The keys to minimizing errors include developing a culture of safety and cooperation, back‐up checks, standardization, automation, and robust training for all those who are involved in the care of a patient on an insulin infusion. Although we encourage standardization and the use of protocols, providers always need to consider the unique clinical circumstances and potential problems presented by each individual patient. It is important to recognize the many barriers to successful implementation of an IIP, but strategies exist to overcome these. Finally, remember that the process does not end with the development phase. Continued review is paramount to success. Note variations in use, analyze them, and learn from them, in order to continually improve the process of care.

Inpatient glycemic control and hypoglycemia are issues with well deserved increased attention in recent years. Prominent guidelines and technical reviews have been published,13 and a recent, randomized controlled trial demonstrated the superiority of basal bolus insulin regimens compared to sliding‐scale regimens.4 Effective glycemic control for inpatients has remained elusive in most medical centers. Recent reports57 detail clinical inertia and the continued widespread use of sliding‐scale subcutaneous insulin regimens, as opposed to the anticipatory, physiologic basal‐nutrition‐correction dose insulin regimens endorsed by these reviews.

Inpatient glycemic control faces a number of barriers, including fears of inducing hypoglycemia, uneven knowledge and training among staff, and competing institutional and patient priorities. These barriers occur in the background of an inherently complex inpatient environment that poses unique challenges in maintaining safe glycemic control. Patients frequently move across a variety of care teams and geographic locations during a single inpatient stay, giving rise to multiple opportunities for failed communication, incomplete handoffs, and inconsistent treatment. In addition, insulin requirements may change dramatically due to variations in the stress of illness, exposure to medications that effect glucose levels, and varied forms of nutritional intake with frequent interruption. Although insulin is recognized as one of the medications most likely to be associated with adverse events in the hospital, many hospitals do not have protocols or order sets in place to standardize its use.

A Call to Action consensus conference,8, 9 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA), brought together many thought leaders and organizations, including representation from the Society of Hospital Medicine (SHM), to address these barriers and to outline components necessary for successful implementation of a program to improve inpatient glycemic control in the face of these difficulties. Institutional insulin management protocols and standardized insulin order sets (supported by appropriate educational efforts) were identified as key interventions. It may be tempting to quickly deploy a generic insulin order set in an effort to improve care. This often results in mediocre results, due to inadequate incorporation of standardization and guidance into the order set and other documentation tools, and uneven use of the order set.

The SHM Glycemic Control Task Force (GCTF) recommends the following steps for developing and implementing successful protocols and order sets addressing the needs of the noncritical care inpatient with diabetes/hyperglycemia.

• Form a steering committee for this work, and assess the current processes of care.

• Identify best practices and preferred regimens to manage diabetes and hyperglycemia in the hospital.

• Integrate best practices and preferred institutional choices into an inpatient glycemic control protocol. Crystallize your protocol into a one page summary.

• Place guidance from your protocol into the flow of work, by integrating it into standardized subcutaneous insulin order sets and other documentation and treatment tools.

• Monitor the use of your order sets and protocol. Intervene actively on nonadherents to your protocol and those with poor glycemic control, and revise your protocol/order sets as needed.

IDENTIFYING AND INCORPORATING KEY CONCEPTS AND BEST PRACTICES

A protocol is a document that endorses specific monitoring and treatment strategies in a given institution. This potentially extensive document should provide guidance for transitions, special situations (like steroids and total parenteral nutrition [TPN]) and should outline preferred insulin regimens for all of the most common nutritional situations. One of the most difficult parts of creating a protocol is the assimilation of all of the important information on which to base decisions. Your protocol and order set will be promoting a set of clinical practices. Fortunately, the current best practice for noncritical care hyperglycemic patients has been summarized by several authoritative sources,13, 811 including references from the SHM Glycemic Task Force published in this supplement.4, 12

Table 1 summarizes the key concepts that should be emphasized in a protocol for subcutaneous insulin management in the hospital. We recommend embedding guidance from your protocol into order sets, the medication administration record, and educational materials. Although the details contained in a protocol and order set might vary from one institution to another, the key concepts should not. The remainder of this article provides practical information about how these concepts and guidance for how preferred insulin regimens should be included in these tools. Appendices 1 and 2 give examples of an institutional one‐page summary protocol and subcutaneous insulin order set, respectively.

PULLING IT ALL TOGETHER: MAKE SURE YOUR PROTOCOL/ORDER SET IS EASY TO USE AND WIDELY UTILIZED

When standardizing hospital management of diabetes and hyperglycemia, we recommend building the full protocol first, then crystallizing the protocol into a one‐page summary that can be widely disseminated. The protocol guidance is then incorporated into the order set and nursing medical administration record (MAR). Again, we recommend the most proscriptive and protocol‐driven order set feasible within the constraints of medical staff support. The example order set in Appendix 2 illustrates this approach along with other desirable features:

• 1

  Check‐box simplicity on when to order appropriate glucose monitoring.

• 2

  Prompt for the proper hyperglycemia‐related diagnosis.

• 3

  Prompts to document diagnosis and to order HbA1c level.

• 4

  Use of encouraged insulin terminology: basal, prandial (or nutritional), and correction. Language is a powerful thing, and just getting staff to use these terms goes a long way toward the more physiologic prescribing of insulin.

• 5

  Statement/reminder of a glycemic goal.

• 6

  Prompts and contact information for appropriate consultation.

• 7

  Elimination of unapproved abbreviations (such as U for units).

• 8

  Stating both generic and brand names of insulin preparations.

• 9

  Important timing cues for administration of insulin.

• 10

  Several correction‐dose scales suitable for different insulin sensitivities. One size does NOT fit all.

• 11

  Incorporation of a simple hypoglycemia protocol into the order set.

• 12

  Insulin dosing guidelines available at the point of care (in this case, on the back of the order set).

Additional nursing‐specific cues (such as an admonition to never mix glargine insulin with other types of insulin) can also be included in the MAR whenever glargine is ordered.

Once you have protocols and order sets to guide providers, you need to assure that they are used for the majority of hyperglycemic patients. Educational programs should introduce your interventions and the rationale for them. In order to make your method the default method of care, your team should survey all preprinted or CPOE insulin order sets of your institution. A review of postoperative, transfer, and admission order sets that all services use may reveal a half‐dozen or more embedded sliding‐scale insulin order sets that should be removed, with prompts to use the standardized insulin order set being placed in their stead.

Computerized order sets present both challenges and opportunities. Wording limitations and the scrolling nature can make concepts less clear, yet there is a capability for incorporating a hierarchical structure that allows for guiding the user through a more algorithmic approach. There is also a capacity to provide assistance with dosing calculations that do not exist in the paper world. Education remains of key importance for both methods.

MONITOR THE USE AND EFFECTIVENESS OF YOUR PROTOCOLS AND ORDER SETS

Creating and implementing protocols, order sets, and other tools is not the end of the journey to improve care. It is important to monitor order set utilization, insulin use patterns, and parameters measuring glycemic control and hypoglycemia, as outlined in more detail in another article in this supplement.16 In addition to summary data every month or so, we recommend daily reports that spur action in near real time. Triggers such as uncontrolled hyperglycemia, markedly elevated HbA1c levels, and nonphysiologic insulin regimens should initiate consultation, extra diabetes education, or referral to a glucose control team. If appropriate consultation is not readily available, the glycemic control steering group should lobby the administration to bolster this capability. Qualitative feedback from the frontline caregivers, as well as this quantitative data, can assist the local glycemic control champions in designing even more effective protocols, order sets, focused educational efforts, and concurrent mitigation of suboptimal care.

CONCLUSION

Diabetes, hyperglycemia, and iatrogenic hypoglycemia are common and important conditions affecting the noncritically ill inpatient. Interventional trials to validate the recommended noncritical care unit glycemic targets are needed. Although there is a growing consensus on best practices to care for these patients, numerous barriers and the complexity of caring for inpatients hamper the reliability of best practice delivery. Institutional protocols and protocol driven subcutaneous insulin orders, when implemented with the strategies outlined here, can be the key to delivering these best practices more reliably.

Inpatient glycemic control and hypoglycemia are issues with well deserved increased attention in recent years. Prominent guidelines and technical reviews have been published,13 and a recent, randomized controlled trial demonstrated the superiority of basal bolus insulin regimens compared to sliding‐scale regimens.4 Effective glycemic control for inpatients has remained elusive in most medical centers. Recent reports57 detail clinical inertia and the continued widespread use of sliding‐scale subcutaneous insulin regimens, as opposed to the anticipatory, physiologic basal‐nutrition‐correction dose insulin regimens endorsed by these reviews.

Inpatient glycemic control faces a number of barriers, including fears of inducing hypoglycemia, uneven knowledge and training among staff, and competing institutional and patient priorities. These barriers occur in the background of an inherently complex inpatient environment that poses unique challenges in maintaining safe glycemic control. Patients frequently move across a variety of care teams and geographic locations during a single inpatient stay, giving rise to multiple opportunities for failed communication, incomplete handoffs, and inconsistent treatment. In addition, insulin requirements may change dramatically due to variations in the stress of illness, exposure to medications that effect glucose levels, and varied forms of nutritional intake with frequent interruption. Although insulin is recognized as one of the medications most likely to be associated with adverse events in the hospital, many hospitals do not have protocols or order sets in place to standardize its use.

A Call to Action consensus conference,8, 9 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA), brought together many thought leaders and organizations, including representation from the Society of Hospital Medicine (SHM), to address these barriers and to outline components necessary for successful implementation of a program to improve inpatient glycemic control in the face of these difficulties. Institutional insulin management protocols and standardized insulin order sets (supported by appropriate educational efforts) were identified as key interventions. It may be tempting to quickly deploy a generic insulin order set in an effort to improve care. This often results in mediocre results, due to inadequate incorporation of standardization and guidance into the order set and other documentation tools, and uneven use of the order set.

The SHM Glycemic Control Task Force (GCTF) recommends the following steps for developing and implementing successful protocols and order sets addressing the needs of the noncritical care inpatient with diabetes/hyperglycemia.

• Form a steering committee for this work, and assess the current processes of care.

• Identify best practices and preferred regimens to manage diabetes and hyperglycemia in the hospital.

• Integrate best practices and preferred institutional choices into an inpatient glycemic control protocol. Crystallize your protocol into a one page summary.

• Place guidance from your protocol into the flow of work, by integrating it into standardized subcutaneous insulin order sets and other documentation and treatment tools.

• Monitor the use of your order sets and protocol. Intervene actively on nonadherents to your protocol and those with poor glycemic control, and revise your protocol/order sets as needed.

IDENTIFYING AND INCORPORATING KEY CONCEPTS AND BEST PRACTICES

A protocol is a document that endorses specific monitoring and treatment strategies in a given institution. This potentially extensive document should provide guidance for transitions, special situations (like steroids and total parenteral nutrition [TPN]) and should outline preferred insulin regimens for all of the most common nutritional situations. One of the most difficult parts of creating a protocol is the assimilation of all of the important information on which to base decisions. Your protocol and order set will be promoting a set of clinical practices. Fortunately, the current best practice for noncritical care hyperglycemic patients has been summarized by several authoritative sources,13, 811 including references from the SHM Glycemic Task Force published in this supplement.4, 12

Table 1 summarizes the key concepts that should be emphasized in a protocol for subcutaneous insulin management in the hospital. We recommend embedding guidance from your protocol into order sets, the medication administration record, and educational materials. Although the details contained in a protocol and order set might vary from one institution to another, the key concepts should not. The remainder of this article provides practical information about how these concepts and guidance for how preferred insulin regimens should be included in these tools. Appendices 1 and 2 give examples of an institutional one‐page summary protocol and subcutaneous insulin order set, respectively.

PULLING IT ALL TOGETHER: MAKE SURE YOUR PROTOCOL/ORDER SET IS EASY TO USE AND WIDELY UTILIZED

When standardizing hospital management of diabetes and hyperglycemia, we recommend building the full protocol first, then crystallizing the protocol into a one‐page summary that can be widely disseminated. The protocol guidance is then incorporated into the order set and nursing medical administration record (MAR). Again, we recommend the most proscriptive and protocol‐driven order set feasible within the constraints of medical staff support. The example order set in Appendix 2 illustrates this approach along with other desirable features:

• 1

  Check‐box simplicity on when to order appropriate glucose monitoring.

• 2

  Prompt for the proper hyperglycemia‐related diagnosis.

• 3

  Prompts to document diagnosis and to order HbA1c level.

• 4

  Use of encouraged insulin terminology: basal, prandial (or nutritional), and correction. Language is a powerful thing, and just getting staff to use these terms goes a long way toward the more physiologic prescribing of insulin.

• 5

  Statement/reminder of a glycemic goal.

• 6

  Prompts and contact information for appropriate consultation.

• 7

  Elimination of unapproved abbreviations (such as U for units).

• 8

  Stating both generic and brand names of insulin preparations.

• 9

  Important timing cues for administration of insulin.

• 10

  Several correction‐dose scales suitable for different insulin sensitivities. One size does NOT fit all.

• 11

  Incorporation of a simple hypoglycemia protocol into the order set.

• 12

  Insulin dosing guidelines available at the point of care (in this case, on the back of the order set).

Additional nursing‐specific cues (such as an admonition to never mix glargine insulin with other types of insulin) can also be included in the MAR whenever glargine is ordered.

Once you have protocols and order sets to guide providers, you need to assure that they are used for the majority of hyperglycemic patients. Educational programs should introduce your interventions and the rationale for them. In order to make your method the default method of care, your team should survey all preprinted or CPOE insulin order sets of your institution. A review of postoperative, transfer, and admission order sets that all services use may reveal a half‐dozen or more embedded sliding‐scale insulin order sets that should be removed, with prompts to use the standardized insulin order set being placed in their stead.

Computerized order sets present both challenges and opportunities. Wording limitations and the scrolling nature can make concepts less clear, yet there is a capability for incorporating a hierarchical structure that allows for guiding the user through a more algorithmic approach. There is also a capacity to provide assistance with dosing calculations that do not exist in the paper world. Education remains of key importance for both methods.

MONITOR THE USE AND EFFECTIVENESS OF YOUR PROTOCOLS AND ORDER SETS

Creating and implementing protocols, order sets, and other tools is not the end of the journey to improve care. It is important to monitor order set utilization, insulin use patterns, and parameters measuring glycemic control and hypoglycemia, as outlined in more detail in another article in this supplement.16 In addition to summary data every month or so, we recommend daily reports that spur action in near real time. Triggers such as uncontrolled hyperglycemia, markedly elevated HbA1c levels, and nonphysiologic insulin regimens should initiate consultation, extra diabetes education, or referral to a glucose control team. If appropriate consultation is not readily available, the glycemic control steering group should lobby the administration to bolster this capability. Qualitative feedback from the frontline caregivers, as well as this quantitative data, can assist the local glycemic control champions in designing even more effective protocols, order sets, focused educational efforts, and concurrent mitigation of suboptimal care.

CONCLUSION

Diabetes, hyperglycemia, and iatrogenic hypoglycemia are common and important conditions affecting the noncritically ill inpatient. Interventional trials to validate the recommended noncritical care unit glycemic targets are needed. Although there is a growing consensus on best practices to care for these patients, numerous barriers and the complexity of caring for inpatients hamper the reliability of best practice delivery. Institutional protocols and protocol driven subcutaneous insulin orders, when implemented with the strategies outlined here, can be the key to delivering these best practices more reliably.

Inpatient glycemic control and hypoglycemia are issues with well deserved increased attention in recent years. Prominent guidelines and technical reviews have been published,13 and a recent, randomized controlled trial demonstrated the superiority of basal bolus insulin regimens compared to sliding‐scale regimens.4 Effective glycemic control for inpatients has remained elusive in most medical centers. Recent reports57 detail clinical inertia and the continued widespread use of sliding‐scale subcutaneous insulin regimens, as opposed to the anticipatory, physiologic basal‐nutrition‐correction dose insulin regimens endorsed by these reviews.

Inpatient glycemic control faces a number of barriers, including fears of inducing hypoglycemia, uneven knowledge and training among staff, and competing institutional and patient priorities. These barriers occur in the background of an inherently complex inpatient environment that poses unique challenges in maintaining safe glycemic control. Patients frequently move across a variety of care teams and geographic locations during a single inpatient stay, giving rise to multiple opportunities for failed communication, incomplete handoffs, and inconsistent treatment. In addition, insulin requirements may change dramatically due to variations in the stress of illness, exposure to medications that effect glucose levels, and varied forms of nutritional intake with frequent interruption. Although insulin is recognized as one of the medications most likely to be associated with adverse events in the hospital, many hospitals do not have protocols or order sets in place to standardize its use.

A Call to Action consensus conference,8, 9 hosted by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA), brought together many thought leaders and organizations, including representation from the Society of Hospital Medicine (SHM), to address these barriers and to outline components necessary for successful implementation of a program to improve inpatient glycemic control in the face of these difficulties. Institutional insulin management protocols and standardized insulin order sets (supported by appropriate educational efforts) were identified as key interventions. It may be tempting to quickly deploy a generic insulin order set in an effort to improve care. This often results in mediocre results, due to inadequate incorporation of standardization and guidance into the order set and other documentation tools, and uneven use of the order set.

The SHM Glycemic Control Task Force (GCTF) recommends the following steps for developing and implementing successful protocols and order sets addressing the needs of the noncritical care inpatient with diabetes/hyperglycemia.

• Form a steering committee for this work, and assess the current processes of care.

• Identify best practices and preferred regimens to manage diabetes and hyperglycemia in the hospital.

• Integrate best practices and preferred institutional choices into an inpatient glycemic control protocol. Crystallize your protocol into a one page summary.

• Place guidance from your protocol into the flow of work, by integrating it into standardized subcutaneous insulin order sets and other documentation and treatment tools.

• Monitor the use of your order sets and protocol. Intervene actively on nonadherents to your protocol and those with poor glycemic control, and revise your protocol/order sets as needed.

IDENTIFYING AND INCORPORATING KEY CONCEPTS AND BEST PRACTICES

A protocol is a document that endorses specific monitoring and treatment strategies in a given institution. This potentially extensive document should provide guidance for transitions, special situations (like steroids and total parenteral nutrition [TPN]) and should outline preferred insulin regimens for all of the most common nutritional situations. One of the most difficult parts of creating a protocol is the assimilation of all of the important information on which to base decisions. Your protocol and order set will be promoting a set of clinical practices. Fortunately, the current best practice for noncritical care hyperglycemic patients has been summarized by several authoritative sources,13, 811 including references from the SHM Glycemic Task Force published in this supplement.4, 12

Table 1 summarizes the key concepts that should be emphasized in a protocol for subcutaneous insulin management in the hospital. We recommend embedding guidance from your protocol into order sets, the medication administration record, and educational materials. Although the details contained in a protocol and order set might vary from one institution to another, the key concepts should not. The remainder of this article provides practical information about how these concepts and guidance for how preferred insulin regimens should be included in these tools. Appendices 1 and 2 give examples of an institutional one‐page summary protocol and subcutaneous insulin order set, respectively.

PULLING IT ALL TOGETHER: MAKE SURE YOUR PROTOCOL/ORDER SET IS EASY TO USE AND WIDELY UTILIZED

When standardizing hospital management of diabetes and hyperglycemia, we recommend building the full protocol first, then crystallizing the protocol into a one‐page summary that can be widely disseminated. The protocol guidance is then incorporated into the order set and nursing medical administration record (MAR). Again, we recommend the most proscriptive and protocol‐driven order set feasible within the constraints of medical staff support. The example order set in Appendix 2 illustrates this approach along with other desirable features:

• 1

  Check‐box simplicity on when to order appropriate glucose monitoring.

• 2

  Prompt for the proper hyperglycemia‐related diagnosis.

• 3

  Prompts to document diagnosis and to order HbA1c level.

• 4

  Use of encouraged insulin terminology: basal, prandial (or nutritional), and correction. Language is a powerful thing, and just getting staff to use these terms goes a long way toward the more physiologic prescribing of insulin.

• 5

  Statement/reminder of a glycemic goal.

• 6

  Prompts and contact information for appropriate consultation.

• 7

  Elimination of unapproved abbreviations (such as U for units).

• 8

  Stating both generic and brand names of insulin preparations.

• 9

  Important timing cues for administration of insulin.

• 10

  Several correction‐dose scales suitable for different insulin sensitivities. One size does NOT fit all.

• 11

  Incorporation of a simple hypoglycemia protocol into the order set.

• 12

  Insulin dosing guidelines available at the point of care (in this case, on the back of the order set).

Additional nursing‐specific cues (such as an admonition to never mix glargine insulin with other types of insulin) can also be included in the MAR whenever glargine is ordered.

Once you have protocols and order sets to guide providers, you need to assure that they are used for the majority of hyperglycemic patients. Educational programs should introduce your interventions and the rationale for them. In order to make your method the default method of care, your team should survey all preprinted or CPOE insulin order sets of your institution. A review of postoperative, transfer, and admission order sets that all services use may reveal a half‐dozen or more embedded sliding‐scale insulin order sets that should be removed, with prompts to use the standardized insulin order set being placed in their stead.

Computerized order sets present both challenges and opportunities. Wording limitations and the scrolling nature can make concepts less clear, yet there is a capability for incorporating a hierarchical structure that allows for guiding the user through a more algorithmic approach. There is also a capacity to provide assistance with dosing calculations that do not exist in the paper world. Education remains of key importance for both methods.

MONITOR THE USE AND EFFECTIVENESS OF YOUR PROTOCOLS AND ORDER SETS

Creating and implementing protocols, order sets, and other tools is not the end of the journey to improve care. It is important to monitor order set utilization, insulin use patterns, and parameters measuring glycemic control and hypoglycemia, as outlined in more detail in another article in this supplement.16 In addition to summary data every month or so, we recommend daily reports that spur action in near real time. Triggers such as uncontrolled hyperglycemia, markedly elevated HbA1c levels, and nonphysiologic insulin regimens should initiate consultation, extra diabetes education, or referral to a glucose control team. If appropriate consultation is not readily available, the glycemic control steering group should lobby the administration to bolster this capability. Qualitative feedback from the frontline caregivers, as well as this quantitative data, can assist the local glycemic control champions in designing even more effective protocols, order sets, focused educational efforts, and concurrent mitigation of suboptimal care.

CONCLUSION

Diabetes, hyperglycemia, and iatrogenic hypoglycemia are common and important conditions affecting the noncritically ill inpatient. Interventional trials to validate the recommended noncritical care unit glycemic targets are needed. Although there is a growing consensus on best practices to care for these patients, numerous barriers and the complexity of caring for inpatients hamper the reliability of best practice delivery. Institutional protocols and protocol driven subcutaneous insulin orders, when implemented with the strategies outlined here, can be the key to delivering these best practices more reliably.

Professional and patient safety organizations have recognized the importance of safe transitions as patients move through the health care system, and such attention is even more critical when attempting to achieve glycemic control.14 Since the publication of the Diabetes Control and Complications Trial (DCCT)5 and the United Kingdom Prospective Diabetes Study (UKPDS),6 we have known that intensive glycemic control in the ambulatory setting prevents complications in both type 1 and type 2 diabetes mellitus (DM). Despite the increased risk of hypoglycemia, these trials changed practice patterns in the outpatient settings in favor of intensification of diabetes therapy. In the same way, randomized, prospective trials using intravenous (IV) insulin therapy have revolutionized our thinking about inpatient care by showing that tight glycemic control in the critically ill7 and patients with acute myocardial infarction8 reduces mortality and morbidity. These, as well as additional observational studies associating hyperglycemia with poor outcomes in a variety of medical and surgical patients,915 have led to increased attention on glycemic control in all venues of care.16, 17 Concerns over excessive hypoglycemia and a nonsignificant increase in mortality in certain populations of medical intensive care unit (ICU) patients have raised questions over whether the initial studies can be reproduced or generalized to other groups of inpatients.18, 19 Additional studies are underway to clarify these questions but consensus exists that blood glucose values should at least be less than 180 mg/dL and that the traditional practice of ignoring hyperglycemia is no longer acceptable.

While a uniform focus on glycemic control will allow our patients to receive a consistent message about diabetes, the unique limitations inherent to each practice setting requires different therapeutic regimens and intentional focus on the risks as patients transition from one care area to another. This work addresses several areas of care transition that are particularly important in safely achieving glycemic control including: transition into the hospital for patients on a variety of home regimens, transitions within the hospital (related to changes in dietary intake, change from IV to subcutaneous [SC] therapy, and the perioperative setting), and the transition from the hospital to home or another healthcare facility.

TRANSITION INTO THE HOSPITAL

Until recently, most patients with diabetes admitted to the hospital were managed with sliding‐scale‐only regimens.20, 21 Unfortunately, this led to a variety of complications, including hyperglycemia, hypoglycemia, iatrogenic ketoacidosis, and an inconsistent message to patients on the importance of glycemic control.22 Some outpatient clinicians and patients combated this tradition by creating in‐hospital glucose control plans with orders, which patients would bring with them to the hospital.23 This practice continues to be a helpful way to guide inpatient therapy and is encouraged when available. Glycemic‐controlrelated documents from outpatient clinicians should include the most recent glycosylated hemoglobin (HbA1c) value, diagnosis and known complications, current names and doses of medications, and other patient‐specific preferences or needs (eg, compliance, financial, fear of needles). If the last HbA1c was performed more than 30 days before admission or is not available, one should be obtained upon hospital admission to help guide discharge therapy.24 By knowing the HbA1c, one can determine the level of diabetic control achieved with the current regimen and can help the inpatient team (clinician and patient) determine if a more aggressive glycemic control regimen is necessary at the time of discharge. It is important to note that if the patient has received a transfusion of red blood cells prior to HbA1c measurement or has a hemoglobinopathy, the HbA1c value may not be accurate.25, 26

In general, the outpatient regimen will need to be modified at admission to achieve the appropriate flexibility needed for the changing nutritional intake and insulin requirements that invariably accompany hospitalization. Sulfonylureas and dipeptidyl peptidase 4 inhibitors (DPP4), such as sitagliptin, have most of their effect immediately, but the other oral antihyperglycemic agents have a relatively long delay between treatment and effect, thus they are not a flexible enough method to achieve glycemic control in the hospital. Additionally, inpatients may have transient contraindications to their prior oral antihyperglycemic medications. Metformin is almost always on hold in the hospital setting, at least initially, due to concerns about lactic acidosis. Sulfonylureas can cause hypoglycemia in the setting of worsening renal function or reduced oral intake. Thiazoladinediones (TZDs) are often withheld due to concerns about fluid retention and should be avoided in patients admitted with heart failure. There is little experience in the hospital with the use of newer agents like exenatide, pramlintide, glinides, and DPP4 inhibitors.

Overall, it is generally recommended that oral antihyperglycemic agents be discontinued upon hospital admission and replaced with insulin infusions or scheduled SC insulin. An estimate of 0.4 to 0.5 units/kg of body weight provides a conservative starting point for the total daily dose of insulin (TDD) for most patients. This TDD should then be divided into basal and nutritional components to match the patients' caloric intake. Additional correction doses of insulin should be prescribed to cover episodes of hyperglycemia that develop despite the provision of anticipatory‐physiologic insulin. Further discussion of insulin dosing and SC regimens is available in detail elsewhere.27, 28 The recommendation for these insulin‐only regimens is made regardless of the glycemic control in the outpatient setting and is not meant to imply that they should be continued at discharge. In fact, most patients will return to their home regimen or to one that is intensified but less labor intensive than the basal‐nutritional‐correction insulin used in the hospital. The antihyperglycemic regimen planned for discharge should be anticipated as early as possible and clearly communicated to the patient and/or caregivers to allow for optimal education.

Outpatient insulin regimens that have a high percentage of basal insulin need to be modified during hospital admission to avoid hypoglycemia that may occur from variable nutritional intake. While hospitalized, the basal portion of the estimated TDD generally should not be more than 50% to 60%. The total number of units of all types of insulin used daily as an outpatient can be used as a starting point for determining the inpatient TDD by a 1:1 conversion. Adjustments up or down based on glycemic control, nutritional intake, and other factors are then necessary. If patients are on regimens with insulin plus oral agents at home, the inpatient TDD should either be the home insulin dose or the dose calculated based on their weight, whichever is greater. Patients who use carbohydrate counting to determine nutritional insulin doses as an outpatient might be continued on this regimen if they have a strong understanding of the methods, they are coherent enough to determine their doses, nursing staff are well educated, and dietary services provides the carbohydrate content for the hospital menu. If patients are on insulin pumps at home, these should be managed according to a uniform hospital policy to assure safety. If conversion to multiple daily injections is needed, the same 1:1 conversion is safe.29