Benjamin Arthur, MD

ILLUSTRATIVE CASE

A 60-year-old woman who is generally healthy except for a history of recurrent urinary tract infections presents to the emergency department with fever, hypotension, and altered mental status, meeting criteria for septic shock. During her resuscitation, supplemental oxygen is administered. Standard treatment calls for a minimum SpO₂ (saturation of peripheral oxygen) > 90%. What should your SpO₂ goal be?

Use of supplemental oxygen in the acute care of the critically ill adult is a common practice in pre-hospital, emergency department (ED), and hospitalized settings.^2,3 Despite their prevalence, guidelines about appropriate oxygen concentration and target SpO₂ levels are often conflicting or vague.^3-5

Excessive oxygen supplementation in acute illness may be harmful and cause increased risk of hypercapnic respiratory failure, delayed recognition of clinical deterioration, and oxygen toxicity.^2,6 The perception of oxygen safety persists despite these findings, and it likely contributes to the ongoing practice of liberal oxygen supplementation in the acutely ill adult.^2,7,8

STUDY SUMMARY

Liberal supplemental O₂ linked to increased mortality

The Improving Oxygen Therapy in Acute illness (IOTA) study was a systematic review and meta-analysis of 25 randomized controlled trials (RCTs) that compared liberal vs conservative oxygen strategies for acutely ill adults (N = 16,037; median age = 64 years; range = 28-76 years). Patients with sepsis, critical illness, stroke, trauma, myocardial infarction, or cardiac arrest, and patients who had emergency surgery were included. Studies were excluded if they involved patients who had chronic respiratory illness or psychiatric diseases, were receiving extracorporeal membrane oxygenation, were undergoing elective surgeries, were being treated with hyperbaric oxygen therapy, or were pregnant.

The outcomes studied were mortality (in-hospital, at 30 days, and at the longest ­follow-up) and morbidity (disability measured by the modified Rankin Scale at longest follow-up, risk of hospital-acquired pneumonia, risk of any hospital-acquired infection, and hospital length of stay).

Liberal supplemental oxygen, above an SpO₂ range of 94% to 96%, increased mortality during inpatient stays (relative risk [RR] = 1.21; 95% confidence interval [CI], 1.03-1.43; N = 15,071), at 30 days (RR = 1.14; 95% CI, 1.01-1.29; N = 15,053), and at longest follow-up (RR = 1.10; 95% CI, 1.00-1.20; N = 15,754; median = 90 days; range = 14,365 days). There was no difference in morbidity outcomes between groups.

While it’s difficult to define a specific target SpO₂ range, the number needed to harm when using a liberal oxygen approach (SpO₂ > 96%) resulting in 1 death was 71 (95% CI, 37-1000).

Continue to: WHAT'S NEW

High-quality evidence points to the dangers of liberal O₂ therapy

This comprehensive meta-analysis is the first high-quality evidence to suggest that liberal use of oxygen in acutely ill adults above a specific SpO₂ level increases all-cause mortality. Previous small RCTs and observational studies have examined the effect of liberal oxygen only on specific presenting conditions, thus making more generalizable conclusions challenging.^9-12

CAVEATS

Varied definitions of “liberal” and “conservative”

This review included studies with variable ranges of SpO₂ defined as liberal vs conservative supplementation. However, in all of these, SpO₂ above 96% was correlated with unfavorable outcomes.

This meta-analysis is the first high-quality evidence to suggest that liberal use of oxygen in acutely ill adults above a specific SpO₂ level increases all-cause mortality.

The study excluded 2 potentially important patient groups: patients with chronic respiratory diseases and pregnant patients. Increased oxygen supplementation in patients with chronic respiratory diseases in noncritical settings has been shown to be deleterious.^13-15 While this study does not address the issue of oxygen supplementation in acutely ill patients with chronic respiratory disease, use should be considered with caution. The results from this study may not be generalizable to women who are pregnant.

CHALLENGES TO IMPLEMENTATION

Reversing the tide

Liberal oxygen administration continues to be practiced in many health care settings. The main challenges to implementing the conclusions of this study are these pervasive practices.

ACKNOWLEDGMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

ILLUSTRATIVE CASE

A 60-year-old woman who is generally healthy except for a history of recurrent urinary tract infections presents to the emergency department with fever, hypotension, and altered mental status, meeting criteria for septic shock. During her resuscitation, supplemental oxygen is administered. Standard treatment calls for a minimum SpO₂ (saturation of peripheral oxygen) > 90%. What should your SpO₂ goal be?

Use of supplemental oxygen in the acute care of the critically ill adult is a common practice in pre-hospital, emergency department (ED), and hospitalized settings.^2,3 Despite their prevalence, guidelines about appropriate oxygen concentration and target SpO₂ levels are often conflicting or vague.^3-5

Excessive oxygen supplementation in acute illness may be harmful and cause increased risk of hypercapnic respiratory failure, delayed recognition of clinical deterioration, and oxygen toxicity.^2,6 The perception of oxygen safety persists despite these findings, and it likely contributes to the ongoing practice of liberal oxygen supplementation in the acutely ill adult.^2,7,8

STUDY SUMMARY

Liberal supplemental O₂ linked to increased mortality

The Improving Oxygen Therapy in Acute illness (IOTA) study was a systematic review and meta-analysis of 25 randomized controlled trials (RCTs) that compared liberal vs conservative oxygen strategies for acutely ill adults (N = 16,037; median age = 64 years; range = 28-76 years). Patients with sepsis, critical illness, stroke, trauma, myocardial infarction, or cardiac arrest, and patients who had emergency surgery were included. Studies were excluded if they involved patients who had chronic respiratory illness or psychiatric diseases, were receiving extracorporeal membrane oxygenation, were undergoing elective surgeries, were being treated with hyperbaric oxygen therapy, or were pregnant.

The outcomes studied were mortality (in-hospital, at 30 days, and at the longest ­follow-up) and morbidity (disability measured by the modified Rankin Scale at longest follow-up, risk of hospital-acquired pneumonia, risk of any hospital-acquired infection, and hospital length of stay).

Liberal supplemental oxygen, above an SpO₂ range of 94% to 96%, increased mortality during inpatient stays (relative risk [RR] = 1.21; 95% confidence interval [CI], 1.03-1.43; N = 15,071), at 30 days (RR = 1.14; 95% CI, 1.01-1.29; N = 15,053), and at longest follow-up (RR = 1.10; 95% CI, 1.00-1.20; N = 15,754; median = 90 days; range = 14,365 days). There was no difference in morbidity outcomes between groups.

While it’s difficult to define a specific target SpO₂ range, the number needed to harm when using a liberal oxygen approach (SpO₂ > 96%) resulting in 1 death was 71 (95% CI, 37-1000).

Continue to: WHAT'S NEW

High-quality evidence points to the dangers of liberal O₂ therapy

This comprehensive meta-analysis is the first high-quality evidence to suggest that liberal use of oxygen in acutely ill adults above a specific SpO₂ level increases all-cause mortality. Previous small RCTs and observational studies have examined the effect of liberal oxygen only on specific presenting conditions, thus making more generalizable conclusions challenging.^9-12

CAVEATS

Varied definitions of “liberal” and “conservative”

This review included studies with variable ranges of SpO₂ defined as liberal vs conservative supplementation. However, in all of these, SpO₂ above 96% was correlated with unfavorable outcomes.

This meta-analysis is the first high-quality evidence to suggest that liberal use of oxygen in acutely ill adults above a specific SpO₂ level increases all-cause mortality.

The study excluded 2 potentially important patient groups: patients with chronic respiratory diseases and pregnant patients. Increased oxygen supplementation in patients with chronic respiratory diseases in noncritical settings has been shown to be deleterious.^13-15 While this study does not address the issue of oxygen supplementation in acutely ill patients with chronic respiratory disease, use should be considered with caution. The results from this study may not be generalizable to women who are pregnant.

CHALLENGES TO IMPLEMENTATION

Reversing the tide

Liberal oxygen administration continues to be practiced in many health care settings. The main challenges to implementing the conclusions of this study are these pervasive practices.

ACKNOWLEDGMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

ILLUSTRATIVE CASE

A 60-year-old woman who is generally healthy except for a history of recurrent urinary tract infections presents to the emergency department with fever, hypotension, and altered mental status, meeting criteria for septic shock. During her resuscitation, supplemental oxygen is administered. Standard treatment calls for a minimum SpO₂ (saturation of peripheral oxygen) > 90%. What should your SpO₂ goal be?

Use of supplemental oxygen in the acute care of the critically ill adult is a common practice in pre-hospital, emergency department (ED), and hospitalized settings.^2,3 Despite their prevalence, guidelines about appropriate oxygen concentration and target SpO₂ levels are often conflicting or vague.^3-5

Excessive oxygen supplementation in acute illness may be harmful and cause increased risk of hypercapnic respiratory failure, delayed recognition of clinical deterioration, and oxygen toxicity.^2,6 The perception of oxygen safety persists despite these findings, and it likely contributes to the ongoing practice of liberal oxygen supplementation in the acutely ill adult.^2,7,8

STUDY SUMMARY

Liberal supplemental O₂ linked to increased mortality

The Improving Oxygen Therapy in Acute illness (IOTA) study was a systematic review and meta-analysis of 25 randomized controlled trials (RCTs) that compared liberal vs conservative oxygen strategies for acutely ill adults (N = 16,037; median age = 64 years; range = 28-76 years). Patients with sepsis, critical illness, stroke, trauma, myocardial infarction, or cardiac arrest, and patients who had emergency surgery were included. Studies were excluded if they involved patients who had chronic respiratory illness or psychiatric diseases, were receiving extracorporeal membrane oxygenation, were undergoing elective surgeries, were being treated with hyperbaric oxygen therapy, or were pregnant.

The outcomes studied were mortality (in-hospital, at 30 days, and at the longest ­follow-up) and morbidity (disability measured by the modified Rankin Scale at longest follow-up, risk of hospital-acquired pneumonia, risk of any hospital-acquired infection, and hospital length of stay).

Liberal supplemental oxygen, above an SpO₂ range of 94% to 96%, increased mortality during inpatient stays (relative risk [RR] = 1.21; 95% confidence interval [CI], 1.03-1.43; N = 15,071), at 30 days (RR = 1.14; 95% CI, 1.01-1.29; N = 15,053), and at longest follow-up (RR = 1.10; 95% CI, 1.00-1.20; N = 15,754; median = 90 days; range = 14,365 days). There was no difference in morbidity outcomes between groups.

While it’s difficult to define a specific target SpO₂ range, the number needed to harm when using a liberal oxygen approach (SpO₂ > 96%) resulting in 1 death was 71 (95% CI, 37-1000).

Continue to: WHAT'S NEW

High-quality evidence points to the dangers of liberal O₂ therapy

This comprehensive meta-analysis is the first high-quality evidence to suggest that liberal use of oxygen in acutely ill adults above a specific SpO₂ level increases all-cause mortality. Previous small RCTs and observational studies have examined the effect of liberal oxygen only on specific presenting conditions, thus making more generalizable conclusions challenging.^9-12

CAVEATS

Varied definitions of “liberal” and “conservative”

This review included studies with variable ranges of SpO₂ defined as liberal vs conservative supplementation. However, in all of these, SpO₂ above 96% was correlated with unfavorable outcomes.

This meta-analysis is the first high-quality evidence to suggest that liberal use of oxygen in acutely ill adults above a specific SpO₂ level increases all-cause mortality.

The study excluded 2 potentially important patient groups: patients with chronic respiratory diseases and pregnant patients. Increased oxygen supplementation in patients with chronic respiratory diseases in noncritical settings has been shown to be deleterious.^13-15 While this study does not address the issue of oxygen supplementation in acutely ill patients with chronic respiratory disease, use should be considered with caution. The results from this study may not be generalizable to women who are pregnant.

CHALLENGES TO IMPLEMENTATION

Reversing the tide

Liberal oxygen administration continues to be practiced in many health care settings. The main challenges to implementing the conclusions of this study are these pervasive practices.

ACKNOWLEDGMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

A 58-year-old man presents to your office with a 2-day history of moderate (6/10) left lower quadrant pain, mild fever (none currently), 2 episodes of vomiting, no diarrhea, and no relief with OTC medications. You suspect diverticulitis and obtain an abdominal CT scan, which shows mild, uncomplicated (Hinchey stage 1a) diverticulitis. How would you treat this patient?

Diverticulitis is common; each year, about 200,000 people in the United States are admitted to the hospital because of it.^2,3 Health care providers typically treat diverticular disease with antibiotics and bowel rest.^2,3 While severe forms of diverticulitis often require parenteral antibiotics and/or surgery, practitioners are increasingly managing the condition with oral antibiotics.⁴

One previous randomized controlled trial (RCT; N = 623) found that antibiotic treatment for acute uncomplicated diverticulitis did not speed recovery or prevent complications (perforation or abscess formation) or recurrence at 12 months.⁵ The study’s strengths included limiting enrollment to people with CT-proven diverticulitis, using a good randomization and concealment process, and employing intention-to-treat analysis. The study was limited by the lack of a standardized antibiotic regimen across centers, previous diverticulitis diagnoses in 40% of patients, nonuniform follow-up processes to confirm anatomic resolution, and the lack of assessment to confirm resolution.⁵

STUDY SUMMARY

Watchful waiting just as effective as antibiotics

This newer study was a single-blind RCT that compared treatment with antibiotics to observation among 528 adults in the Netherlands. Patients were enrolled if they had CT-proven, primary, left-sided, uncomplicated acute diverticulitis (Hinchey stage 1a and 1b).¹ (The Hinchey classification is based on radiologic findings, with 0 for clinical diverticulitis only, 1a for confined pericolic inflammation or phlegmon, and 1b for pericolic or mesocolic abscess.⁶) Exclusion criteria included suspicion of colonic cancer by CT or ultrasound (US), previous CT/US-proven diverticulitis, sepsis, pregnancy, or antibiotic use in the previous 4 weeks.¹

Observational vs antibiotic treatment. Enrolled patients were randomly assigned to receive amoxicillin-clavulanate (1,200 mg by IV qid for at least 48 hours, followed by 625 mg po tid, for 10 total days; n = 266) or to be observed (n = 262). Randomization was performed by computer, with a random varying block size and stratification by Hinchey classification and center; allocation was concealed. The investigators were masked to the allocation until all analyses were completed.¹

The primary outcome was the time to functional recovery (resumption of pre-illness work activities) during a 6-month follow-up period. Secondary outcomes included hospital readmission rate; complicated, ongoing, and recurrent diverticulitis; sigmoid resection; other nonsurgical intervention; antibiotic adverse effects; and all-cause mortality.

Results. Median recovery time for observational treatment was not inferior to antibiotic treatment (14 d vs 12 d; hazard ratio for functional recovery, 0.91). Observation was not inferior to antibiotics for any of the secondary endpoints at 6 and 12 months of follow-up: complicated diverticulitis (3.8% vs 2.6%, respectively), recurrent diverticulitis (3.4% vs 3%), readmission (17.6% vs 12%), or adverse events (48.5% vs 54.5%). Initial hospitalization length of stay was shorter in the observation group (2 vs 3 d). The researchers conducted a 24-month telephone follow-up, but no differences from the 12-month follow-up were noted.¹

Continue to: WHAT'S NEW

WHAT’S NEW

Study looked at true patient-oriented ­outcome

Previous studies of treatment options for acute uncomplicated diverticulitis looked at short-term outcomes, or at readmission, recurrence, and surgical intervention rate or requirement for percutaneous drainage.^7,8 This study is the first to look at functional return to work (a true patient-oriented outcome). And it is the only study to follow up at 24 months to gauge long-term outcomes with observational treatment.

CAVEATS

Can’t generalize to worse cases

It is worth noting that the findings of this study apply only to the mildest form of CT-proven acute diverticulitis (those patients classified as having Hinchey 1a disease) and are not generalizable to patients with more severe forms. Not enough patients with Hinchey 1b acute diverticulitis were enrolled in the study to reach any conclusions about treatment.

Various guidelines issued outside the United States recommend antibiotics for uncomplicated diverticulitis; however, the American Gastroenterological Association (AGA) indicates that antibiotics should be used selectively.^1,9,10 This recommendation was based on an emerging understanding that diverticulitis may be more inflammatory than infectious in nature. The AGA guideline authors acknowledge that their conclusion was based on low-quality evidence.⁹

CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to implementing this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2018. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice (2018;67[7]:435-436,438).

A 58-year-old man presents to your office with a 2-day history of moderate (6/10) left lower quadrant pain, mild fever (none currently), 2 episodes of vomiting, no diarrhea, and no relief with OTC medications. You suspect diverticulitis and obtain an abdominal CT scan, which shows mild, uncomplicated (Hinchey stage 1a) diverticulitis. How would you treat this patient?

Diverticulitis is common; each year, about 200,000 people in the United States are admitted to the hospital because of it.^2,3 Health care providers typically treat diverticular disease with antibiotics and bowel rest.^2,3 While severe forms of diverticulitis often require parenteral antibiotics and/or surgery, practitioners are increasingly managing the condition with oral antibiotics.⁴

One previous randomized controlled trial (RCT; N = 623) found that antibiotic treatment for acute uncomplicated diverticulitis did not speed recovery or prevent complications (perforation or abscess formation) or recurrence at 12 months.⁵ The study’s strengths included limiting enrollment to people with CT-proven diverticulitis, using a good randomization and concealment process, and employing intention-to-treat analysis. The study was limited by the lack of a standardized antibiotic regimen across centers, previous diverticulitis diagnoses in 40% of patients, nonuniform follow-up processes to confirm anatomic resolution, and the lack of assessment to confirm resolution.⁵

STUDY SUMMARY

Watchful waiting just as effective as antibiotics

This newer study was a single-blind RCT that compared treatment with antibiotics to observation among 528 adults in the Netherlands. Patients were enrolled if they had CT-proven, primary, left-sided, uncomplicated acute diverticulitis (Hinchey stage 1a and 1b).¹ (The Hinchey classification is based on radiologic findings, with 0 for clinical diverticulitis only, 1a for confined pericolic inflammation or phlegmon, and 1b for pericolic or mesocolic abscess.⁶) Exclusion criteria included suspicion of colonic cancer by CT or ultrasound (US), previous CT/US-proven diverticulitis, sepsis, pregnancy, or antibiotic use in the previous 4 weeks.¹

Observational vs antibiotic treatment. Enrolled patients were randomly assigned to receive amoxicillin-clavulanate (1,200 mg by IV qid for at least 48 hours, followed by 625 mg po tid, for 10 total days; n = 266) or to be observed (n = 262). Randomization was performed by computer, with a random varying block size and stratification by Hinchey classification and center; allocation was concealed. The investigators were masked to the allocation until all analyses were completed.¹

The primary outcome was the time to functional recovery (resumption of pre-illness work activities) during a 6-month follow-up period. Secondary outcomes included hospital readmission rate; complicated, ongoing, and recurrent diverticulitis; sigmoid resection; other nonsurgical intervention; antibiotic adverse effects; and all-cause mortality.

Results. Median recovery time for observational treatment was not inferior to antibiotic treatment (14 d vs 12 d; hazard ratio for functional recovery, 0.91). Observation was not inferior to antibiotics for any of the secondary endpoints at 6 and 12 months of follow-up: complicated diverticulitis (3.8% vs 2.6%, respectively), recurrent diverticulitis (3.4% vs 3%), readmission (17.6% vs 12%), or adverse events (48.5% vs 54.5%). Initial hospitalization length of stay was shorter in the observation group (2 vs 3 d). The researchers conducted a 24-month telephone follow-up, but no differences from the 12-month follow-up were noted.¹

Continue to: WHAT'S NEW

WHAT’S NEW

Study looked at true patient-oriented ­outcome

Previous studies of treatment options for acute uncomplicated diverticulitis looked at short-term outcomes, or at readmission, recurrence, and surgical intervention rate or requirement for percutaneous drainage.^7,8 This study is the first to look at functional return to work (a true patient-oriented outcome). And it is the only study to follow up at 24 months to gauge long-term outcomes with observational treatment.

CAVEATS

Can’t generalize to worse cases

It is worth noting that the findings of this study apply only to the mildest form of CT-proven acute diverticulitis (those patients classified as having Hinchey 1a disease) and are not generalizable to patients with more severe forms. Not enough patients with Hinchey 1b acute diverticulitis were enrolled in the study to reach any conclusions about treatment.

Various guidelines issued outside the United States recommend antibiotics for uncomplicated diverticulitis; however, the American Gastroenterological Association (AGA) indicates that antibiotics should be used selectively.^1,9,10 This recommendation was based on an emerging understanding that diverticulitis may be more inflammatory than infectious in nature. The AGA guideline authors acknowledge that their conclusion was based on low-quality evidence.⁹

CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to implementing this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2018. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice (2018;67[7]:435-436,438).

A 58-year-old man presents to your office with a 2-day history of moderate (6/10) left lower quadrant pain, mild fever (none currently), 2 episodes of vomiting, no diarrhea, and no relief with OTC medications. You suspect diverticulitis and obtain an abdominal CT scan, which shows mild, uncomplicated (Hinchey stage 1a) diverticulitis. How would you treat this patient?

Diverticulitis is common; each year, about 200,000 people in the United States are admitted to the hospital because of it.^2,3 Health care providers typically treat diverticular disease with antibiotics and bowel rest.^2,3 While severe forms of diverticulitis often require parenteral antibiotics and/or surgery, practitioners are increasingly managing the condition with oral antibiotics.⁴

One previous randomized controlled trial (RCT; N = 623) found that antibiotic treatment for acute uncomplicated diverticulitis did not speed recovery or prevent complications (perforation or abscess formation) or recurrence at 12 months.⁵ The study’s strengths included limiting enrollment to people with CT-proven diverticulitis, using a good randomization and concealment process, and employing intention-to-treat analysis. The study was limited by the lack of a standardized antibiotic regimen across centers, previous diverticulitis diagnoses in 40% of patients, nonuniform follow-up processes to confirm anatomic resolution, and the lack of assessment to confirm resolution.⁵

STUDY SUMMARY

Watchful waiting just as effective as antibiotics

This newer study was a single-blind RCT that compared treatment with antibiotics to observation among 528 adults in the Netherlands. Patients were enrolled if they had CT-proven, primary, left-sided, uncomplicated acute diverticulitis (Hinchey stage 1a and 1b).¹ (The Hinchey classification is based on radiologic findings, with 0 for clinical diverticulitis only, 1a for confined pericolic inflammation or phlegmon, and 1b for pericolic or mesocolic abscess.⁶) Exclusion criteria included suspicion of colonic cancer by CT or ultrasound (US), previous CT/US-proven diverticulitis, sepsis, pregnancy, or antibiotic use in the previous 4 weeks.¹

Observational vs antibiotic treatment. Enrolled patients were randomly assigned to receive amoxicillin-clavulanate (1,200 mg by IV qid for at least 48 hours, followed by 625 mg po tid, for 10 total days; n = 266) or to be observed (n = 262). Randomization was performed by computer, with a random varying block size and stratification by Hinchey classification and center; allocation was concealed. The investigators were masked to the allocation until all analyses were completed.¹

The primary outcome was the time to functional recovery (resumption of pre-illness work activities) during a 6-month follow-up period. Secondary outcomes included hospital readmission rate; complicated, ongoing, and recurrent diverticulitis; sigmoid resection; other nonsurgical intervention; antibiotic adverse effects; and all-cause mortality.

Results. Median recovery time for observational treatment was not inferior to antibiotic treatment (14 d vs 12 d; hazard ratio for functional recovery, 0.91). Observation was not inferior to antibiotics for any of the secondary endpoints at 6 and 12 months of follow-up: complicated diverticulitis (3.8% vs 2.6%, respectively), recurrent diverticulitis (3.4% vs 3%), readmission (17.6% vs 12%), or adverse events (48.5% vs 54.5%). Initial hospitalization length of stay was shorter in the observation group (2 vs 3 d). The researchers conducted a 24-month telephone follow-up, but no differences from the 12-month follow-up were noted.¹

Continue to: WHAT'S NEW

WHAT’S NEW

Study looked at true patient-oriented ­outcome

Previous studies of treatment options for acute uncomplicated diverticulitis looked at short-term outcomes, or at readmission, recurrence, and surgical intervention rate or requirement for percutaneous drainage.^7,8 This study is the first to look at functional return to work (a true patient-oriented outcome). And it is the only study to follow up at 24 months to gauge long-term outcomes with observational treatment.

CAVEATS

Can’t generalize to worse cases

It is worth noting that the findings of this study apply only to the mildest form of CT-proven acute diverticulitis (those patients classified as having Hinchey 1a disease) and are not generalizable to patients with more severe forms. Not enough patients with Hinchey 1b acute diverticulitis were enrolled in the study to reach any conclusions about treatment.

Various guidelines issued outside the United States recommend antibiotics for uncomplicated diverticulitis; however, the American Gastroenterological Association (AGA) indicates that antibiotics should be used selectively.^1,9,10 This recommendation was based on an emerging understanding that diverticulitis may be more inflammatory than infectious in nature. The AGA guideline authors acknowledge that their conclusion was based on low-quality evidence.⁹

CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to implementing this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2018. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice (2018;67[7]:435-436,438).

ILLUSTRATIVE CASE

A 58-year-old man presents to your office with a 2-day history of moderate (6/10) left lower quadrant pain, mild fever (none currently), 2 episodes of vomiting, no diarrhea, and no relief with over-the-counter medications. You suspect diverticulitis and obtain an abdominal computed tomography (CT) scan, which shows mild, uncomplicated (Hinchey stage 1a) diverticulitis.

How would you treat him?

Diverticulitis is common; about 200,000 people per year are admitted to the hospital because of diverticulitis in the United States.^2,3 Health care providers typically treat diverticular disease with antibiotics and bowel rest.^2,3 While severe forms of diverticulitis often require parenteral antibiotics and/or surgery, practitioners are increasingly managing the condition with oral antibiotics.⁴

One previous randomized control trial (RCT; N=623) found that antibiotic treatment (compared with no antibiotic treatment) for acute uncomplicated diverticulitis did not speed recovery or prevent complications (perforation or abscess formation) or recurrence at 12 months.⁵ The study’s strengths included limiting enrollment to people with CT-proven diverticulitis, using a good randomization and concealment process, and employing intention-to-treat analysis. The study was limited by a lack of a standardized antibiotic regimen across centers, previous diverticulitis diagnoses in 40% of patients, non-uniform follow-up processes to confirm anatomic resolution, and the lack of assessment to confirm resolution.⁵

STUDY SUMMARY

RCT finds that watchful waiting is just as effective as antibiotic Tx

This newer study was a single-blind RCT that compared treatment with antibiotics to observation among 528 adult patients in the Netherlands. Patients were enrolled if they had CT-proven, primary, left-sided, uncomplicated acute diverticulitis (Hinchey stage 1a and 1b).¹ (The Hinchey classification is based on radiologic findings, with 0 for clinical diverticulitis only, 1a for confined pericolic inflammation or phlegmon, and 1b for pericolic or mesocolic abscess.⁶) Exclusion criteria included suspicion of colonic cancer by CT or ultrasound (US), previous CT/US-proven diverticulitis, sepsis, pregnancy, or antibiotic use in the previous 4 weeks.¹

Observational vs antibiotic treatment. Enrolled patients were randomized to receive IV administration of amoxicillin-clavulanate 1200 mg 4 times daily for at least 48 hours followed by 625 mg PO 3 times daily for 10 total days of antibiotic treatment (n=266) or to be observed (n=262). Computerized randomization, with a random varying block size and stratified by Hinchey classification and center, was performed, and allocation was concealed. The investigators were masked to the allocation until all analyses were completed.¹

The primary outcome was the time to functional recovery (resumption of pre-illness work activities) during a 6-month follow-up period. Secondary outcomes included hospital readmission rate; complicated, ongoing, and recurrent diverticulitis; sigmoid resection; other nonsurgical intervention; antibiotic treatment adverse effects; and all-cause mortality.

Continue to: Results

This study is the first to look at functional return to work and the only study to gauge long-term outcomes with observational treatment.

Results. Median recovery time for observational treatment was not inferior to antibiotic treatment (14 days vs 12 days; P=.15; hazard ratio [HR] for functional recovery=0.91; lower limit of 1-sided 95% confidence interval, 0.78). Observation was not inferior to antibiotics for any of the secondary endpoints at 6 and 12 months of follow-up (complicated diverticulitis, 3.8% vs 2.6%, respectively; P=.377), recurrent diverticulitis (3.4% vs 3%; P=.494), readmission (17.6% vs 12%; P=.148), or adverse events (48.5% vs 54.5%; P=.221). Initial hospitalization length of stay was shorter in the observation group (2 vs 3 days; P=.006). The researchers conducted a 24-month telephone follow-up, but no differences from the 12-month follow-up were noted.¹

WHAT’S NEW

A study that looks at a true patient-oriented outcome

Previous studies of treatment options for acute uncomplicated diverticulitis looked at short-term outcomes, or at readmission, recurrence, and surgical intervention rate, or requirement for percutaneous drainage.^7,8 This study is the first one to look at functional return to work (a true patient-oriented outcome). And it is the only study to look out to 24 months to gauge long-term outcomes with observational treatment.

CAVEATS

Can’t generalize findings to patients with worse forms of diverticulitis

It is worth noting that the findings of this study apply only to the mildest form of CT-proven acute diverticulitis (those patients classified as having Hinchey 1a disease), and is not generalizable to patients with more severe forms. Not enough patients with Hinchey 1b acute diverticulitis were enrolled in the study to reach any conclusions about treatment.

Various guidelines issued outside the United States recommend antibiotics for uncomplicated diverticulitis; however, the American Gastroenterological Association (AGA) indicates that antibiotics should be used selectively.^1,9,10 This recommendation was based on an emerging understanding that diverticulitis maybe more inflammatory than infectious in nature. The AGA guideline authors acknowledge that their conclusion was based on low-quality evidence.⁹

Continuet to: CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to implementing this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

ILLUSTRATIVE CASE

A 58-year-old man presents to your office with a 2-day history of moderate (6/10) left lower quadrant pain, mild fever (none currently), 2 episodes of vomiting, no diarrhea, and no relief with over-the-counter medications. You suspect diverticulitis and obtain an abdominal computed tomography (CT) scan, which shows mild, uncomplicated (Hinchey stage 1a) diverticulitis.

How would you treat him?

Diverticulitis is common; about 200,000 people per year are admitted to the hospital because of diverticulitis in the United States.^2,3 Health care providers typically treat diverticular disease with antibiotics and bowel rest.^2,3 While severe forms of diverticulitis often require parenteral antibiotics and/or surgery, practitioners are increasingly managing the condition with oral antibiotics.⁴

One previous randomized control trial (RCT; N=623) found that antibiotic treatment (compared with no antibiotic treatment) for acute uncomplicated diverticulitis did not speed recovery or prevent complications (perforation or abscess formation) or recurrence at 12 months.⁵ The study’s strengths included limiting enrollment to people with CT-proven diverticulitis, using a good randomization and concealment process, and employing intention-to-treat analysis. The study was limited by a lack of a standardized antibiotic regimen across centers, previous diverticulitis diagnoses in 40% of patients, non-uniform follow-up processes to confirm anatomic resolution, and the lack of assessment to confirm resolution.⁵

STUDY SUMMARY

RCT finds that watchful waiting is just as effective as antibiotic Tx

This newer study was a single-blind RCT that compared treatment with antibiotics to observation among 528 adult patients in the Netherlands. Patients were enrolled if they had CT-proven, primary, left-sided, uncomplicated acute diverticulitis (Hinchey stage 1a and 1b).¹ (The Hinchey classification is based on radiologic findings, with 0 for clinical diverticulitis only, 1a for confined pericolic inflammation or phlegmon, and 1b for pericolic or mesocolic abscess.⁶) Exclusion criteria included suspicion of colonic cancer by CT or ultrasound (US), previous CT/US-proven diverticulitis, sepsis, pregnancy, or antibiotic use in the previous 4 weeks.¹

Observational vs antibiotic treatment. Enrolled patients were randomized to receive IV administration of amoxicillin-clavulanate 1200 mg 4 times daily for at least 48 hours followed by 625 mg PO 3 times daily for 10 total days of antibiotic treatment (n=266) or to be observed (n=262). Computerized randomization, with a random varying block size and stratified by Hinchey classification and center, was performed, and allocation was concealed. The investigators were masked to the allocation until all analyses were completed.¹

The primary outcome was the time to functional recovery (resumption of pre-illness work activities) during a 6-month follow-up period. Secondary outcomes included hospital readmission rate; complicated, ongoing, and recurrent diverticulitis; sigmoid resection; other nonsurgical intervention; antibiotic treatment adverse effects; and all-cause mortality.

Continue to: Results

This study is the first to look at functional return to work and the only study to gauge long-term outcomes with observational treatment.

Results. Median recovery time for observational treatment was not inferior to antibiotic treatment (14 days vs 12 days; P=.15; hazard ratio [HR] for functional recovery=0.91; lower limit of 1-sided 95% confidence interval, 0.78). Observation was not inferior to antibiotics for any of the secondary endpoints at 6 and 12 months of follow-up (complicated diverticulitis, 3.8% vs 2.6%, respectively; P=.377), recurrent diverticulitis (3.4% vs 3%; P=.494), readmission (17.6% vs 12%; P=.148), or adverse events (48.5% vs 54.5%; P=.221). Initial hospitalization length of stay was shorter in the observation group (2 vs 3 days; P=.006). The researchers conducted a 24-month telephone follow-up, but no differences from the 12-month follow-up were noted.¹

WHAT’S NEW

A study that looks at a true patient-oriented outcome

Previous studies of treatment options for acute uncomplicated diverticulitis looked at short-term outcomes, or at readmission, recurrence, and surgical intervention rate, or requirement for percutaneous drainage.^7,8 This study is the first one to look at functional return to work (a true patient-oriented outcome). And it is the only study to look out to 24 months to gauge long-term outcomes with observational treatment.

CAVEATS

Can’t generalize findings to patients with worse forms of diverticulitis

It is worth noting that the findings of this study apply only to the mildest form of CT-proven acute diverticulitis (those patients classified as having Hinchey 1a disease), and is not generalizable to patients with more severe forms. Not enough patients with Hinchey 1b acute diverticulitis were enrolled in the study to reach any conclusions about treatment.

Various guidelines issued outside the United States recommend antibiotics for uncomplicated diverticulitis; however, the American Gastroenterological Association (AGA) indicates that antibiotics should be used selectively.^1,9,10 This recommendation was based on an emerging understanding that diverticulitis maybe more inflammatory than infectious in nature. The AGA guideline authors acknowledge that their conclusion was based on low-quality evidence.⁹

Continuet to: CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to implementing this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

ILLUSTRATIVE CASE

A 58-year-old man presents to your office with a 2-day history of moderate (6/10) left lower quadrant pain, mild fever (none currently), 2 episodes of vomiting, no diarrhea, and no relief with over-the-counter medications. You suspect diverticulitis and obtain an abdominal computed tomography (CT) scan, which shows mild, uncomplicated (Hinchey stage 1a) diverticulitis.

How would you treat him?

Diverticulitis is common; about 200,000 people per year are admitted to the hospital because of diverticulitis in the United States.^2,3 Health care providers typically treat diverticular disease with antibiotics and bowel rest.^2,3 While severe forms of diverticulitis often require parenteral antibiotics and/or surgery, practitioners are increasingly managing the condition with oral antibiotics.⁴

One previous randomized control trial (RCT; N=623) found that antibiotic treatment (compared with no antibiotic treatment) for acute uncomplicated diverticulitis did not speed recovery or prevent complications (perforation or abscess formation) or recurrence at 12 months.⁵ The study’s strengths included limiting enrollment to people with CT-proven diverticulitis, using a good randomization and concealment process, and employing intention-to-treat analysis. The study was limited by a lack of a standardized antibiotic regimen across centers, previous diverticulitis diagnoses in 40% of patients, non-uniform follow-up processes to confirm anatomic resolution, and the lack of assessment to confirm resolution.⁵

STUDY SUMMARY

RCT finds that watchful waiting is just as effective as antibiotic Tx

This newer study was a single-blind RCT that compared treatment with antibiotics to observation among 528 adult patients in the Netherlands. Patients were enrolled if they had CT-proven, primary, left-sided, uncomplicated acute diverticulitis (Hinchey stage 1a and 1b).¹ (The Hinchey classification is based on radiologic findings, with 0 for clinical diverticulitis only, 1a for confined pericolic inflammation or phlegmon, and 1b for pericolic or mesocolic abscess.⁶) Exclusion criteria included suspicion of colonic cancer by CT or ultrasound (US), previous CT/US-proven diverticulitis, sepsis, pregnancy, or antibiotic use in the previous 4 weeks.¹

Observational vs antibiotic treatment. Enrolled patients were randomized to receive IV administration of amoxicillin-clavulanate 1200 mg 4 times daily for at least 48 hours followed by 625 mg PO 3 times daily for 10 total days of antibiotic treatment (n=266) or to be observed (n=262). Computerized randomization, with a random varying block size and stratified by Hinchey classification and center, was performed, and allocation was concealed. The investigators were masked to the allocation until all analyses were completed.¹

The primary outcome was the time to functional recovery (resumption of pre-illness work activities) during a 6-month follow-up period. Secondary outcomes included hospital readmission rate; complicated, ongoing, and recurrent diverticulitis; sigmoid resection; other nonsurgical intervention; antibiotic treatment adverse effects; and all-cause mortality.

Continue to: Results

This study is the first to look at functional return to work and the only study to gauge long-term outcomes with observational treatment.

Results. Median recovery time for observational treatment was not inferior to antibiotic treatment (14 days vs 12 days; P=.15; hazard ratio [HR] for functional recovery=0.91; lower limit of 1-sided 95% confidence interval, 0.78). Observation was not inferior to antibiotics for any of the secondary endpoints at 6 and 12 months of follow-up (complicated diverticulitis, 3.8% vs 2.6%, respectively; P=.377), recurrent diverticulitis (3.4% vs 3%; P=.494), readmission (17.6% vs 12%; P=.148), or adverse events (48.5% vs 54.5%; P=.221). Initial hospitalization length of stay was shorter in the observation group (2 vs 3 days; P=.006). The researchers conducted a 24-month telephone follow-up, but no differences from the 12-month follow-up were noted.¹

WHAT’S NEW

A study that looks at a true patient-oriented outcome

Previous studies of treatment options for acute uncomplicated diverticulitis looked at short-term outcomes, or at readmission, recurrence, and surgical intervention rate, or requirement for percutaneous drainage.^7,8 This study is the first one to look at functional return to work (a true patient-oriented outcome). And it is the only study to look out to 24 months to gauge long-term outcomes with observational treatment.

CAVEATS

Can’t generalize findings to patients with worse forms of diverticulitis

It is worth noting that the findings of this study apply only to the mildest form of CT-proven acute diverticulitis (those patients classified as having Hinchey 1a disease), and is not generalizable to patients with more severe forms. Not enough patients with Hinchey 1b acute diverticulitis were enrolled in the study to reach any conclusions about treatment.

Various guidelines issued outside the United States recommend antibiotics for uncomplicated diverticulitis; however, the American Gastroenterological Association (AGA) indicates that antibiotics should be used selectively.^1,9,10 This recommendation was based on an emerging understanding that diverticulitis maybe more inflammatory than infectious in nature. The AGA guideline authors acknowledge that their conclusion was based on low-quality evidence.⁹

Continuet to: CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to implementing this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.