Expert Commentary

This statistical tour de force on the topic of tocolytic therapy attempts to determine which agents are most effective at delaying delivery. The analysis is not a typical meta-analysis but what the investigators refer to as “network meta-analysis,” the distinction being that the latter makes an assumption of consistency because all relevant data are compared, including treatments that may no longer appear to be effective or relevant. This distinction may be a bit too esoteric for most clinicians, me included.

Details of the trial

Investigators identified 95 randomized, controlled trials of tocolytic therapy.

The probability of delivery being delayed by 48 hours was greatest with prostaglandin inhibitors (odds ratio [OR], 5.39; 95% confidence interval [CI], 2.14–12.34), followed by magnesium sulfate (OR, 2.76; 95% CI, 1.58–4.94), calcium channel blockers (OR, 2.71; 95% CI, 1.17–5.91), beta mimetics (OR, 2.41; 95% CI, 1.27–4.55), and the oxytocin receptor blocker atosiban (OR, 2.02; 95% CI, 1.10–3.80), compared with placebo.

No class of tocolytic was superior to placebo in reducing the incidence of neonatal respiratory distress syndrome.

Side effects that required a change of medication were significantly more common with beta mimetics (OR, 22.68; 95% CI, 7.51–73.67), magnesium sulfate (OR, 8.15; 95% CI, 2.47–27.70), and calcium channel blockers (OR, 3.80; 95% CI, 1.02–16.92), compared with placebo.

Prostaglandin inhibitors and calcium channel blockers were the agents most likely to be ranked in the top three classes of medication for the outcomes of a 48-hour delay in delivery, lower risk of respiratory distress syndrome and neonatal mortality, and fewer maternal side effects.

Strengths and limitations

The major strength of this analysis is its inclusion of trials from the world literature.

Weaknesses include the:

• lack of practice standardization in many trials
• inclusion of many trials that used composite or secondary analysis
• inability to control for the inclusion of magnesium sulfate in more recent trials, when it was classified as a neuroprotective agent and not a tocolytic
• inclusion of studies involving drugs unavailable in the United States.

The investigators also made some decisions about which trials to include and exclude that could have confused the picture. For example, they excluded trials that used combination drug therapy for tocolysis. As a result, the use of magnesium sulfate as a neuroprotective agent could have confounded the results if it was not recorded as a tocolytic when used in conjunction with another tocolytic.

The most recent practice bulletin from the American College of Obstetricians and Gynecologists addresses this point when it cautions practitioners about developing guidelines for concurrent tocolytic use when employing magnesium sulfate for fetal neuroprotection.¹ The practice bulletin also confirms Level A evidence for the use of beta-agonists, calcium channel blockers, or nonsteroidal anti-inflammatory drugs for short-term tocolysis, effectively summarizing current clinical practice and agreeing with the conclusions of Haas and colleagues.

Overall, Haas and colleagues affirm current practice, concluding that prostaglandin inhibitors (eg, indomethacin) and calcium channel blockers (eg, nifedipine, nicardipine) delay delivery and improve short-term neonatal outcomes, whereas beta-agonist therapy was not considered to be as preferable, largely due to its maternal side effect profile. In addition, it is difficult to decipher the relative contributions of the drugs described in this investigation to neonatal and maternal side effects.

We want to hear from you! Tell us what you think.

This statistical tour de force on the topic of tocolytic therapy attempts to determine which agents are most effective at delaying delivery. The analysis is not a typical meta-analysis but what the investigators refer to as “network meta-analysis,” the distinction being that the latter makes an assumption of consistency because all relevant data are compared, including treatments that may no longer appear to be effective or relevant. This distinction may be a bit too esoteric for most clinicians, me included.

Details of the trial

Investigators identified 95 randomized, controlled trials of tocolytic therapy.

The probability of delivery being delayed by 48 hours was greatest with prostaglandin inhibitors (odds ratio [OR], 5.39; 95% confidence interval [CI], 2.14–12.34), followed by magnesium sulfate (OR, 2.76; 95% CI, 1.58–4.94), calcium channel blockers (OR, 2.71; 95% CI, 1.17–5.91), beta mimetics (OR, 2.41; 95% CI, 1.27–4.55), and the oxytocin receptor blocker atosiban (OR, 2.02; 95% CI, 1.10–3.80), compared with placebo.

No class of tocolytic was superior to placebo in reducing the incidence of neonatal respiratory distress syndrome.

Side effects that required a change of medication were significantly more common with beta mimetics (OR, 22.68; 95% CI, 7.51–73.67), magnesium sulfate (OR, 8.15; 95% CI, 2.47–27.70), and calcium channel blockers (OR, 3.80; 95% CI, 1.02–16.92), compared with placebo.

Prostaglandin inhibitors and calcium channel blockers were the agents most likely to be ranked in the top three classes of medication for the outcomes of a 48-hour delay in delivery, lower risk of respiratory distress syndrome and neonatal mortality, and fewer maternal side effects.

Strengths and limitations

The major strength of this analysis is its inclusion of trials from the world literature.

Weaknesses include the:

• lack of practice standardization in many trials
• inclusion of many trials that used composite or secondary analysis
• inability to control for the inclusion of magnesium sulfate in more recent trials, when it was classified as a neuroprotective agent and not a tocolytic
• inclusion of studies involving drugs unavailable in the United States.

The investigators also made some decisions about which trials to include and exclude that could have confused the picture. For example, they excluded trials that used combination drug therapy for tocolysis. As a result, the use of magnesium sulfate as a neuroprotective agent could have confounded the results if it was not recorded as a tocolytic when used in conjunction with another tocolytic.

The most recent practice bulletin from the American College of Obstetricians and Gynecologists addresses this point when it cautions practitioners about developing guidelines for concurrent tocolytic use when employing magnesium sulfate for fetal neuroprotection.¹ The practice bulletin also confirms Level A evidence for the use of beta-agonists, calcium channel blockers, or nonsteroidal anti-inflammatory drugs for short-term tocolysis, effectively summarizing current clinical practice and agreeing with the conclusions of Haas and colleagues.

Overall, Haas and colleagues affirm current practice, concluding that prostaglandin inhibitors (eg, indomethacin) and calcium channel blockers (eg, nifedipine, nicardipine) delay delivery and improve short-term neonatal outcomes, whereas beta-agonist therapy was not considered to be as preferable, largely due to its maternal side effect profile. In addition, it is difficult to decipher the relative contributions of the drugs described in this investigation to neonatal and maternal side effects.

We want to hear from you! Tell us what you think.

This statistical tour de force on the topic of tocolytic therapy attempts to determine which agents are most effective at delaying delivery. The analysis is not a typical meta-analysis but what the investigators refer to as “network meta-analysis,” the distinction being that the latter makes an assumption of consistency because all relevant data are compared, including treatments that may no longer appear to be effective or relevant. This distinction may be a bit too esoteric for most clinicians, me included.

Details of the trial

Investigators identified 95 randomized, controlled trials of tocolytic therapy.

The probability of delivery being delayed by 48 hours was greatest with prostaglandin inhibitors (odds ratio [OR], 5.39; 95% confidence interval [CI], 2.14–12.34), followed by magnesium sulfate (OR, 2.76; 95% CI, 1.58–4.94), calcium channel blockers (OR, 2.71; 95% CI, 1.17–5.91), beta mimetics (OR, 2.41; 95% CI, 1.27–4.55), and the oxytocin receptor blocker atosiban (OR, 2.02; 95% CI, 1.10–3.80), compared with placebo.

No class of tocolytic was superior to placebo in reducing the incidence of neonatal respiratory distress syndrome.

Side effects that required a change of medication were significantly more common with beta mimetics (OR, 22.68; 95% CI, 7.51–73.67), magnesium sulfate (OR, 8.15; 95% CI, 2.47–27.70), and calcium channel blockers (OR, 3.80; 95% CI, 1.02–16.92), compared with placebo.

Prostaglandin inhibitors and calcium channel blockers were the agents most likely to be ranked in the top three classes of medication for the outcomes of a 48-hour delay in delivery, lower risk of respiratory distress syndrome and neonatal mortality, and fewer maternal side effects.

Strengths and limitations

The major strength of this analysis is its inclusion of trials from the world literature.

Weaknesses include the:

• lack of practice standardization in many trials
• inclusion of many trials that used composite or secondary analysis
• inability to control for the inclusion of magnesium sulfate in more recent trials, when it was classified as a neuroprotective agent and not a tocolytic
• inclusion of studies involving drugs unavailable in the United States.

The investigators also made some decisions about which trials to include and exclude that could have confused the picture. For example, they excluded trials that used combination drug therapy for tocolysis. As a result, the use of magnesium sulfate as a neuroprotective agent could have confounded the results if it was not recorded as a tocolytic when used in conjunction with another tocolytic.

The most recent practice bulletin from the American College of Obstetricians and Gynecologists addresses this point when it cautions practitioners about developing guidelines for concurrent tocolytic use when employing magnesium sulfate for fetal neuroprotection.¹ The practice bulletin also confirms Level A evidence for the use of beta-agonists, calcium channel blockers, or nonsteroidal anti-inflammatory drugs for short-term tocolysis, effectively summarizing current clinical practice and agreeing with the conclusions of Haas and colleagues.

Overall, Haas and colleagues affirm current practice, concluding that prostaglandin inhibitors (eg, indomethacin) and calcium channel blockers (eg, nifedipine, nicardipine) delay delivery and improve short-term neonatal outcomes, whereas beta-agonist therapy was not considered to be as preferable, largely due to its maternal side effect profile. In addition, it is difficult to decipher the relative contributions of the drugs described in this investigation to neonatal and maternal side effects.

We want to hear from you! Tell us what you think.

In 2007, we and our colleagues began assessing the experience necessary to gain proficiency with robotic hysterectomy, and we published our findings early this year.¹ We concluded that the number of cases needed to reach this threshold is about 91—many more than the 20 to 50 cases previously reported.^2-4 Earlier studies defined proficiency in relation to the stabilization of operative times, which is subjective, somewhat arbitrary, and ignores patient outcomes.

To better elucidate the learning curve of robotic hysterectomy, we focused on a more objective, patient-centered analysis that utilized cumulative summation, or CUSUM, analysis and operative complications. This approach mitigates many of the problems encountered in earlier studies and reveals broader implications for the adoption of new surgical techniques and surgical quality control.

How CUSUM analysis works

E. S. Page introduced CUSUM analysis in 1954 for use in industrial quality control.⁵ This approach has been applied more recently to the construction of learning curves in cardiac surgery, general surgery, and anesthesiology.^6-9 Standard CUSUM methodology defines each event—in our study, each robotic hysterectomy case—as a success or failure and tracks the sequence of events between two predefined parameters—the acceptable control limit and the unacceptable control limit. For each success, the CUSUM score decreases toward the acceptable control limit; for each failure, it increases toward the unacceptable limit.

In our study, a procedure was considered a success if no complication occurred; it was a failure if a complication did occur. The acceptable control limit was based on published complication rates of abdominal hysterectomy, and the unacceptable limit was set at twice that rate. A surgeon would be considered proficient when his or her CUSUM chart crosses the lower control limit, signifying that the surgeon’s complication rate is lower than the rate associated with abdominal hysterectomy. We used abdominal complication rates rather than those of laparoscopic hysterectomy because only abdominal and vaginal hysterectomy were performed at our institution, and the robotic system was introduced as a minimally invasive alternative to the abdominal approach.

We also conducted a risk-adjusted CUSUM analysis that was weighted for identified risk factors for complications. As in the standard CUSUM analysis, each score decreases for a successful attempt and increases for an unsuccessful attempt, but the scores are variable, depending on patient risk factors. That is, the score increases more for a complication in a low-risk patient than in a high-risk patient, and vice versa.

Instead of tracking between acceptable and unacceptable limits, the CUSUM scores were plotted around a line representing a predicted complication rate to determine whether complications for a particular surgeon were occurring more often, less often, or as predicted, based on patient risk factors.

Results based on intraoperative complications. With the score based only on intraoperative complications, we observed one surgeon to cross the acceptable control limit after 96 cases and a second surgeon to be trending toward a similar crossing point, although this surgeon had completed only 76 procedures. We calculated the average number of cases needed to develop proficiency to be 91 to cross the acceptable control limit.

Results based on intraoperative and postoperative complications. We also conducted a second analysis that was based on intraoperative and postoperative complications within 6 weeks of surgery. Our two surgeons crossed the acceptable control limit after 21 and 14 cases, respectively, using these parameters. We calculated the average number of cases needed to cross the acceptable control limit to be 44. We considered intraoperative complications to be most indicative of surgical skill; therefore, we concluded that 91 cases are needed to become proficient.

Any learning curve is an individual process

Our findings should not be used as a blanket mark of proficiency. Our conclusion is at first striking, but must be viewed within the context of CUSUM methodology. Ninety-one hysterectomy cases is an average number based on acceptable and unacceptable complication rates; we found it to be consistent with our observations of two active robotic surgeons.

However, any learning curve—not just in robotic hysterectomy—is an individual process dependent on many variables. An experienced, high-volume laparoscopic surgeon may reach proficiency with robotic hysterectomy in many fewer cases than our ballpark number of 91, just as an inexperienced, low-volume surgeon may take many more than 91 procedures to become proficient. Some surgeons may never become proficient. For these reasons, it is inappropriate to assign any single number as a mark of proficiency. Because of its original intent, CUSUM analysis assesses each surgeon on an individual basis and compares that surgeon to an objective benchmark, enabling it to take individual variances in surgeon attributes into account.

CUSUM analysis is a useful tool for surgical quality monitoring

Because it was designed for quality control, this methodology is most suitable when it is applied to assess a surgeon’s progress toward (or away from) proficiency, rather than to assign a representative number to classify a surgeon as proficient. By tracking a surgeon’s particular successes or failures with a procedure, CUSUM analysis can identify problems in an individual’s surgical quality.

If complication rates are tracking near, or cross, the unacceptable control limit using the standard method, or if they trend upward, away from the predicted complication rate with the risk-adjusted method, this fact should arouse concern so that the problem can be identified before patient safety is compromised.

Potential problems contributing to increased complications

Identifiable contributors to an increased complication rate could be intrinsic to the surgeon, such as:

• inadequate training
• low surgical volume
• sleep deprivation
• other personal issues.

Problems extrinsic to the surgeon also could be identified, such as:

• new policy changes in the surgical suite
• new staff assistance during cases
• excessive trainee involvement in surgery.

Ideally, both the standard and risk-adjusted CUSUM methods would be based on institution-specific complication rates and patient risk factors to make them internally valid. In this scenario, CUSUM analysis provides an opportunity for intervention to improve surgical quality and patient outcomes not only in robotic hysterectomy but also in any surgical procedure.

A surgeon’s proficiency waxes and wanes

At its most fundamental level, a learning curve for robotic surgery should be considered an individual continuum. A surgeon’s proficiency will wax and wane throughout his or her career, depending on any number of variables, including surgical volume, case complexity, practice setting, and personal attributes.

Although our findings suggest that a gynecologist, on average, will require 91 cases to become proficient in robotic hysterectomy, an overall benefit of robotic hysterectomy over abdominal hysterectomy was observed after completion of 21 and 14 cases by our two surgeons. We do not believe that credentialing bodies should mandate that 91 robotic hysterectomies be required of a surgeon. That approach would be too simplistic and obfuscates many of the true implications of our study—most importantly, that learning a new procedure is an individual process that must be compared with an acceptable outcome to determine proficiency and maintain patient safety.

In 2007, we and our colleagues began assessing the experience necessary to gain proficiency with robotic hysterectomy, and we published our findings early this year.¹ We concluded that the number of cases needed to reach this threshold is about 91—many more than the 20 to 50 cases previously reported.^2-4 Earlier studies defined proficiency in relation to the stabilization of operative times, which is subjective, somewhat arbitrary, and ignores patient outcomes.

To better elucidate the learning curve of robotic hysterectomy, we focused on a more objective, patient-centered analysis that utilized cumulative summation, or CUSUM, analysis and operative complications. This approach mitigates many of the problems encountered in earlier studies and reveals broader implications for the adoption of new surgical techniques and surgical quality control.

How CUSUM analysis works

E. S. Page introduced CUSUM analysis in 1954 for use in industrial quality control.⁵ This approach has been applied more recently to the construction of learning curves in cardiac surgery, general surgery, and anesthesiology.^6-9 Standard CUSUM methodology defines each event—in our study, each robotic hysterectomy case—as a success or failure and tracks the sequence of events between two predefined parameters—the acceptable control limit and the unacceptable control limit. For each success, the CUSUM score decreases toward the acceptable control limit; for each failure, it increases toward the unacceptable limit.

In our study, a procedure was considered a success if no complication occurred; it was a failure if a complication did occur. The acceptable control limit was based on published complication rates of abdominal hysterectomy, and the unacceptable limit was set at twice that rate. A surgeon would be considered proficient when his or her CUSUM chart crosses the lower control limit, signifying that the surgeon’s complication rate is lower than the rate associated with abdominal hysterectomy. We used abdominal complication rates rather than those of laparoscopic hysterectomy because only abdominal and vaginal hysterectomy were performed at our institution, and the robotic system was introduced as a minimally invasive alternative to the abdominal approach.

We also conducted a risk-adjusted CUSUM analysis that was weighted for identified risk factors for complications. As in the standard CUSUM analysis, each score decreases for a successful attempt and increases for an unsuccessful attempt, but the scores are variable, depending on patient risk factors. That is, the score increases more for a complication in a low-risk patient than in a high-risk patient, and vice versa.

Instead of tracking between acceptable and unacceptable limits, the CUSUM scores were plotted around a line representing a predicted complication rate to determine whether complications for a particular surgeon were occurring more often, less often, or as predicted, based on patient risk factors.

Results based on intraoperative complications. With the score based only on intraoperative complications, we observed one surgeon to cross the acceptable control limit after 96 cases and a second surgeon to be trending toward a similar crossing point, although this surgeon had completed only 76 procedures. We calculated the average number of cases needed to develop proficiency to be 91 to cross the acceptable control limit.

Results based on intraoperative and postoperative complications. We also conducted a second analysis that was based on intraoperative and postoperative complications within 6 weeks of surgery. Our two surgeons crossed the acceptable control limit after 21 and 14 cases, respectively, using these parameters. We calculated the average number of cases needed to cross the acceptable control limit to be 44. We considered intraoperative complications to be most indicative of surgical skill; therefore, we concluded that 91 cases are needed to become proficient.

Any learning curve is an individual process

Our findings should not be used as a blanket mark of proficiency. Our conclusion is at first striking, but must be viewed within the context of CUSUM methodology. Ninety-one hysterectomy cases is an average number based on acceptable and unacceptable complication rates; we found it to be consistent with our observations of two active robotic surgeons.

However, any learning curve—not just in robotic hysterectomy—is an individual process dependent on many variables. An experienced, high-volume laparoscopic surgeon may reach proficiency with robotic hysterectomy in many fewer cases than our ballpark number of 91, just as an inexperienced, low-volume surgeon may take many more than 91 procedures to become proficient. Some surgeons may never become proficient. For these reasons, it is inappropriate to assign any single number as a mark of proficiency. Because of its original intent, CUSUM analysis assesses each surgeon on an individual basis and compares that surgeon to an objective benchmark, enabling it to take individual variances in surgeon attributes into account.

CUSUM analysis is a useful tool for surgical quality monitoring

Because it was designed for quality control, this methodology is most suitable when it is applied to assess a surgeon’s progress toward (or away from) proficiency, rather than to assign a representative number to classify a surgeon as proficient. By tracking a surgeon’s particular successes or failures with a procedure, CUSUM analysis can identify problems in an individual’s surgical quality.

If complication rates are tracking near, or cross, the unacceptable control limit using the standard method, or if they trend upward, away from the predicted complication rate with the risk-adjusted method, this fact should arouse concern so that the problem can be identified before patient safety is compromised.

Potential problems contributing to increased complications

Identifiable contributors to an increased complication rate could be intrinsic to the surgeon, such as:

• inadequate training
• low surgical volume
• sleep deprivation
• other personal issues.

Problems extrinsic to the surgeon also could be identified, such as:

• new policy changes in the surgical suite
• new staff assistance during cases
• excessive trainee involvement in surgery.

Ideally, both the standard and risk-adjusted CUSUM methods would be based on institution-specific complication rates and patient risk factors to make them internally valid. In this scenario, CUSUM analysis provides an opportunity for intervention to improve surgical quality and patient outcomes not only in robotic hysterectomy but also in any surgical procedure.

A surgeon’s proficiency waxes and wanes

At its most fundamental level, a learning curve for robotic surgery should be considered an individual continuum. A surgeon’s proficiency will wax and wane throughout his or her career, depending on any number of variables, including surgical volume, case complexity, practice setting, and personal attributes.

Although our findings suggest that a gynecologist, on average, will require 91 cases to become proficient in robotic hysterectomy, an overall benefit of robotic hysterectomy over abdominal hysterectomy was observed after completion of 21 and 14 cases by our two surgeons. We do not believe that credentialing bodies should mandate that 91 robotic hysterectomies be required of a surgeon. That approach would be too simplistic and obfuscates many of the true implications of our study—most importantly, that learning a new procedure is an individual process that must be compared with an acceptable outcome to determine proficiency and maintain patient safety.

In 2007, we and our colleagues began assessing the experience necessary to gain proficiency with robotic hysterectomy, and we published our findings early this year.¹ We concluded that the number of cases needed to reach this threshold is about 91—many more than the 20 to 50 cases previously reported.^2-4 Earlier studies defined proficiency in relation to the stabilization of operative times, which is subjective, somewhat arbitrary, and ignores patient outcomes.

To better elucidate the learning curve of robotic hysterectomy, we focused on a more objective, patient-centered analysis that utilized cumulative summation, or CUSUM, analysis and operative complications. This approach mitigates many of the problems encountered in earlier studies and reveals broader implications for the adoption of new surgical techniques and surgical quality control.

How CUSUM analysis works

E. S. Page introduced CUSUM analysis in 1954 for use in industrial quality control.⁵ This approach has been applied more recently to the construction of learning curves in cardiac surgery, general surgery, and anesthesiology.^6-9 Standard CUSUM methodology defines each event—in our study, each robotic hysterectomy case—as a success or failure and tracks the sequence of events between two predefined parameters—the acceptable control limit and the unacceptable control limit. For each success, the CUSUM score decreases toward the acceptable control limit; for each failure, it increases toward the unacceptable limit.

In our study, a procedure was considered a success if no complication occurred; it was a failure if a complication did occur. The acceptable control limit was based on published complication rates of abdominal hysterectomy, and the unacceptable limit was set at twice that rate. A surgeon would be considered proficient when his or her CUSUM chart crosses the lower control limit, signifying that the surgeon’s complication rate is lower than the rate associated with abdominal hysterectomy. We used abdominal complication rates rather than those of laparoscopic hysterectomy because only abdominal and vaginal hysterectomy were performed at our institution, and the robotic system was introduced as a minimally invasive alternative to the abdominal approach.

We also conducted a risk-adjusted CUSUM analysis that was weighted for identified risk factors for complications. As in the standard CUSUM analysis, each score decreases for a successful attempt and increases for an unsuccessful attempt, but the scores are variable, depending on patient risk factors. That is, the score increases more for a complication in a low-risk patient than in a high-risk patient, and vice versa.

Instead of tracking between acceptable and unacceptable limits, the CUSUM scores were plotted around a line representing a predicted complication rate to determine whether complications for a particular surgeon were occurring more often, less often, or as predicted, based on patient risk factors.

Results based on intraoperative complications. With the score based only on intraoperative complications, we observed one surgeon to cross the acceptable control limit after 96 cases and a second surgeon to be trending toward a similar crossing point, although this surgeon had completed only 76 procedures. We calculated the average number of cases needed to develop proficiency to be 91 to cross the acceptable control limit.

Results based on intraoperative and postoperative complications. We also conducted a second analysis that was based on intraoperative and postoperative complications within 6 weeks of surgery. Our two surgeons crossed the acceptable control limit after 21 and 14 cases, respectively, using these parameters. We calculated the average number of cases needed to cross the acceptable control limit to be 44. We considered intraoperative complications to be most indicative of surgical skill; therefore, we concluded that 91 cases are needed to become proficient.

Any learning curve is an individual process

Our findings should not be used as a blanket mark of proficiency. Our conclusion is at first striking, but must be viewed within the context of CUSUM methodology. Ninety-one hysterectomy cases is an average number based on acceptable and unacceptable complication rates; we found it to be consistent with our observations of two active robotic surgeons.

However, any learning curve—not just in robotic hysterectomy—is an individual process dependent on many variables. An experienced, high-volume laparoscopic surgeon may reach proficiency with robotic hysterectomy in many fewer cases than our ballpark number of 91, just as an inexperienced, low-volume surgeon may take many more than 91 procedures to become proficient. Some surgeons may never become proficient. For these reasons, it is inappropriate to assign any single number as a mark of proficiency. Because of its original intent, CUSUM analysis assesses each surgeon on an individual basis and compares that surgeon to an objective benchmark, enabling it to take individual variances in surgeon attributes into account.

CUSUM analysis is a useful tool for surgical quality monitoring

Because it was designed for quality control, this methodology is most suitable when it is applied to assess a surgeon’s progress toward (or away from) proficiency, rather than to assign a representative number to classify a surgeon as proficient. By tracking a surgeon’s particular successes or failures with a procedure, CUSUM analysis can identify problems in an individual’s surgical quality.

If complication rates are tracking near, or cross, the unacceptable control limit using the standard method, or if they trend upward, away from the predicted complication rate with the risk-adjusted method, this fact should arouse concern so that the problem can be identified before patient safety is compromised.

Potential problems contributing to increased complications

Identifiable contributors to an increased complication rate could be intrinsic to the surgeon, such as:

• inadequate training
• low surgical volume
• sleep deprivation
• other personal issues.

Problems extrinsic to the surgeon also could be identified, such as:

• new policy changes in the surgical suite
• new staff assistance during cases
• excessive trainee involvement in surgery.

Ideally, both the standard and risk-adjusted CUSUM methods would be based on institution-specific complication rates and patient risk factors to make them internally valid. In this scenario, CUSUM analysis provides an opportunity for intervention to improve surgical quality and patient outcomes not only in robotic hysterectomy but also in any surgical procedure.

A surgeon’s proficiency waxes and wanes

At its most fundamental level, a learning curve for robotic surgery should be considered an individual continuum. A surgeon’s proficiency will wax and wane throughout his or her career, depending on any number of variables, including surgical volume, case complexity, practice setting, and personal attributes.

Although our findings suggest that a gynecologist, on average, will require 91 cases to become proficient in robotic hysterectomy, an overall benefit of robotic hysterectomy over abdominal hysterectomy was observed after completion of 21 and 14 cases by our two surgeons. We do not believe that credentialing bodies should mandate that 91 robotic hysterectomies be required of a surgeon. That approach would be too simplistic and obfuscates many of the true implications of our study—most importantly, that learning a new procedure is an individual process that must be compared with an acceptable outcome to determine proficiency and maintain patient safety.

Shoulder dystocia is an obstetric complication that occurs in up to 1.4% of deliveries.¹ Although the vast majority can be managed successfully, the complication is associated with risk of fetal injury. The most serious injury is brachial plexus palsy, which occurs in 4% to 40% of shoulder dystocia cases, although less than 10% of these injuries are permanent. Other injuries include fractures of the clavicle and humerus; in rare instances the complication may be associated with fetal asphyxia and death. Early recognition of the complication followed by an orderly approach to management will reduce the risk of fetal injury.

First, recognize shoulder dystocia and take control

Recognition of shoulder dystocia immediately followed by avoidance of further impaction, particularly of the anterior shoulder against the symphysis pubis, will likely increase the chances of successful resolution.

These factors should lead you to anticipate shoulder dystocia during delivery:

• suspected macrosomia
• diabetic parturient
• prolonged second stage.

However, a high percentage of cases occur in women without risk factors. Because persistent or forceful traction, used in an attempt to deliver the anterior shoulder, may be one of the causes of brachial plexus injury, early recognition of shoulder dystocia, followed by a halt of further traction, reduces the risk of that injury.

In my experience, if some movement of the anterior shoulder does not occur after 2 to 3 seconds of gentle downward guidance, you need to consider the possibility of shoulder dystocia. It is also important to take control of the situation: Instruct the patient to stop pushing and family members to stop urging the patient to push.

Avoid panic. Initiate a care-team management algorithm.

Having a management algorithm that can be quickly recalled and initiated allows the care team to proceed in an orderly fashion and remain calm and avoid panic, particularly if the dystocia is severe. In obstetric emergencies, panic is your enemy, leading to inefficient activity, team confusion, and an increased likelihood that an error in judgment (too much traction, fundal pressure) may occur. I advise my residents that whenever there are risk factors for shoulder dystocia, or it is suspected for any reason, to do a mental run-through of the management steps.

Rehearse the algorithm. It will make a difference in the delivery room.

To most effectively use a management algorithm, rehearsal using team training drills or simulation is necessary. Studies support simulation and team training even for individuals who have completed training in obstetrics or midwifery. Crofts and colleagues videotaped 450 simulations of shoulder dystocia involving 95 certified nurse midwives and 45 physicians.² The authors noted that 1) shoulder dystocia could not be resolved in 57% of cases, and 2) there was frequent confusion regarding how to perform the internal maneuvers, with poor communication among team members. This same group of researchers later demonstrated that skills in managing shoulder dystocia improved significantly after simulation training. In fact, a high proportion of “trainees” maintained their skill level when tested a year later.³

Finally, when evaluating the impact of training on actual clinical outcomes in their hospital, Crofts and colleagues noted that the rate of obstetric brachial plexus injury fell from 7.4% in a 4-year period prior to training, to 2.3% in a 4-year period after training.⁴

Practice within your own L&D unit

The use of in situ simulation (ie, simulation within the labor and delivery unit) has two major advantages:

• It is more realistic than practicing within a lab. Systems issues, such as lack of a uniform procedure for getting help or a lack of chairs in the labor room to assist with performance of suprapubic pressure, can be identified.
• The full team, including ward clerks and other support personnel, can be part of the simulation more readily.

The box on this page provides a possible process to use in managing shoulder dystocia. If there has not been an opportunity for this training, practitioners, at the very least, should be cognizant of the steps they are going to take in managing such cases.

What should you do after primary maneuvers fail?

Try to deliver the posterior arm. Although the order of maneuvers in the proposed algorithm may vary, a recent study using a database of more than 130,000 deliveries suggests that use of posterior arm delivery after failure of primary maneuvers, such as McRoberts or suprapubic pressure, may more likely result in resolution.⁵

Start from the beginning, and try again. If the first set of maneuvers does not resolve the problem, running through them again usually leads to success. Although the risk of fetal hypoxia increases the longer it takes to resolve the dystocia, it may actually facilitate delivery because fetal tone may also decrease.

Zavanelli maneuver. In general, use of the Zavanelli maneuver with replacement of the fetal head accompanied by cesarean section is a last resort; there is a lack of data to support its use earlier in the process or more frequently. This maneuver requires reversing the cardinal movements related to head descent in order to successfully complete replacement.

Shoulder dystocia in obese patients proves more difficult

In my own experience with obese patients, suprapubic pressure is often ineffective due to the presence of a large fat pad or pannus. Use of an anterior Rubin’s maneuver to rotate the shoulders about 30° to the oblique often facilitates delivery.

Liberal use of episiotomy to facilitate posterior arm delivery or rotational maneuvers is often necessary with obese patients.

Documentation is key

Documentation of the dystocia event in the patient’s permanent record should not occur until after the care team has discussed the case. This will ensure that the maneuvers utilized and the related timing of events are recorded accurately. This is critically important should a lawsuit occur, since discrepancies or errors in charting will hamper defense of the case. A checklist, such as the one provided by the American College of Obstetricians and Gynecologists, lists key points that should be recorded and outlines important steps related to the event.⁶

We want to hear from you! Tell us what you think.

Shoulder dystocia is an obstetric complication that occurs in up to 1.4% of deliveries.¹ Although the vast majority can be managed successfully, the complication is associated with risk of fetal injury. The most serious injury is brachial plexus palsy, which occurs in 4% to 40% of shoulder dystocia cases, although less than 10% of these injuries are permanent. Other injuries include fractures of the clavicle and humerus; in rare instances the complication may be associated with fetal asphyxia and death. Early recognition of the complication followed by an orderly approach to management will reduce the risk of fetal injury.

First, recognize shoulder dystocia and take control

Recognition of shoulder dystocia immediately followed by avoidance of further impaction, particularly of the anterior shoulder against the symphysis pubis, will likely increase the chances of successful resolution.

These factors should lead you to anticipate shoulder dystocia during delivery:

• suspected macrosomia
• diabetic parturient
• prolonged second stage.

However, a high percentage of cases occur in women without risk factors. Because persistent or forceful traction, used in an attempt to deliver the anterior shoulder, may be one of the causes of brachial plexus injury, early recognition of shoulder dystocia, followed by a halt of further traction, reduces the risk of that injury.

In my experience, if some movement of the anterior shoulder does not occur after 2 to 3 seconds of gentle downward guidance, you need to consider the possibility of shoulder dystocia. It is also important to take control of the situation: Instruct the patient to stop pushing and family members to stop urging the patient to push.

Avoid panic. Initiate a care-team management algorithm.

Having a management algorithm that can be quickly recalled and initiated allows the care team to proceed in an orderly fashion and remain calm and avoid panic, particularly if the dystocia is severe. In obstetric emergencies, panic is your enemy, leading to inefficient activity, team confusion, and an increased likelihood that an error in judgment (too much traction, fundal pressure) may occur. I advise my residents that whenever there are risk factors for shoulder dystocia, or it is suspected for any reason, to do a mental run-through of the management steps.

Rehearse the algorithm. It will make a difference in the delivery room.

To most effectively use a management algorithm, rehearsal using team training drills or simulation is necessary. Studies support simulation and team training even for individuals who have completed training in obstetrics or midwifery. Crofts and colleagues videotaped 450 simulations of shoulder dystocia involving 95 certified nurse midwives and 45 physicians.² The authors noted that 1) shoulder dystocia could not be resolved in 57% of cases, and 2) there was frequent confusion regarding how to perform the internal maneuvers, with poor communication among team members. This same group of researchers later demonstrated that skills in managing shoulder dystocia improved significantly after simulation training. In fact, a high proportion of “trainees” maintained their skill level when tested a year later.³

Finally, when evaluating the impact of training on actual clinical outcomes in their hospital, Crofts and colleagues noted that the rate of obstetric brachial plexus injury fell from 7.4% in a 4-year period prior to training, to 2.3% in a 4-year period after training.⁴

Practice within your own L&D unit

The use of in situ simulation (ie, simulation within the labor and delivery unit) has two major advantages:

• It is more realistic than practicing within a lab. Systems issues, such as lack of a uniform procedure for getting help or a lack of chairs in the labor room to assist with performance of suprapubic pressure, can be identified.
• The full team, including ward clerks and other support personnel, can be part of the simulation more readily.

The box on this page provides a possible process to use in managing shoulder dystocia. If there has not been an opportunity for this training, practitioners, at the very least, should be cognizant of the steps they are going to take in managing such cases.

What should you do after primary maneuvers fail?

Try to deliver the posterior arm. Although the order of maneuvers in the proposed algorithm may vary, a recent study using a database of more than 130,000 deliveries suggests that use of posterior arm delivery after failure of primary maneuvers, such as McRoberts or suprapubic pressure, may more likely result in resolution.⁵

Start from the beginning, and try again. If the first set of maneuvers does not resolve the problem, running through them again usually leads to success. Although the risk of fetal hypoxia increases the longer it takes to resolve the dystocia, it may actually facilitate delivery because fetal tone may also decrease.

Zavanelli maneuver. In general, use of the Zavanelli maneuver with replacement of the fetal head accompanied by cesarean section is a last resort; there is a lack of data to support its use earlier in the process or more frequently. This maneuver requires reversing the cardinal movements related to head descent in order to successfully complete replacement.

Shoulder dystocia in obese patients proves more difficult

In my own experience with obese patients, suprapubic pressure is often ineffective due to the presence of a large fat pad or pannus. Use of an anterior Rubin’s maneuver to rotate the shoulders about 30° to the oblique often facilitates delivery.

Liberal use of episiotomy to facilitate posterior arm delivery or rotational maneuvers is often necessary with obese patients.

Documentation is key

Documentation of the dystocia event in the patient’s permanent record should not occur until after the care team has discussed the case. This will ensure that the maneuvers utilized and the related timing of events are recorded accurately. This is critically important should a lawsuit occur, since discrepancies or errors in charting will hamper defense of the case. A checklist, such as the one provided by the American College of Obstetricians and Gynecologists, lists key points that should be recorded and outlines important steps related to the event.⁶

We want to hear from you! Tell us what you think.

Shoulder dystocia is an obstetric complication that occurs in up to 1.4% of deliveries.¹ Although the vast majority can be managed successfully, the complication is associated with risk of fetal injury. The most serious injury is brachial plexus palsy, which occurs in 4% to 40% of shoulder dystocia cases, although less than 10% of these injuries are permanent. Other injuries include fractures of the clavicle and humerus; in rare instances the complication may be associated with fetal asphyxia and death. Early recognition of the complication followed by an orderly approach to management will reduce the risk of fetal injury.

First, recognize shoulder dystocia and take control

Recognition of shoulder dystocia immediately followed by avoidance of further impaction, particularly of the anterior shoulder against the symphysis pubis, will likely increase the chances of successful resolution.

These factors should lead you to anticipate shoulder dystocia during delivery:

• suspected macrosomia
• diabetic parturient
• prolonged second stage.

However, a high percentage of cases occur in women without risk factors. Because persistent or forceful traction, used in an attempt to deliver the anterior shoulder, may be one of the causes of brachial plexus injury, early recognition of shoulder dystocia, followed by a halt of further traction, reduces the risk of that injury.

In my experience, if some movement of the anterior shoulder does not occur after 2 to 3 seconds of gentle downward guidance, you need to consider the possibility of shoulder dystocia. It is also important to take control of the situation: Instruct the patient to stop pushing and family members to stop urging the patient to push.

Avoid panic. Initiate a care-team management algorithm.

Having a management algorithm that can be quickly recalled and initiated allows the care team to proceed in an orderly fashion and remain calm and avoid panic, particularly if the dystocia is severe. In obstetric emergencies, panic is your enemy, leading to inefficient activity, team confusion, and an increased likelihood that an error in judgment (too much traction, fundal pressure) may occur. I advise my residents that whenever there are risk factors for shoulder dystocia, or it is suspected for any reason, to do a mental run-through of the management steps.

Rehearse the algorithm. It will make a difference in the delivery room.

To most effectively use a management algorithm, rehearsal using team training drills or simulation is necessary. Studies support simulation and team training even for individuals who have completed training in obstetrics or midwifery. Crofts and colleagues videotaped 450 simulations of shoulder dystocia involving 95 certified nurse midwives and 45 physicians.² The authors noted that 1) shoulder dystocia could not be resolved in 57% of cases, and 2) there was frequent confusion regarding how to perform the internal maneuvers, with poor communication among team members. This same group of researchers later demonstrated that skills in managing shoulder dystocia improved significantly after simulation training. In fact, a high proportion of “trainees” maintained their skill level when tested a year later.³

Finally, when evaluating the impact of training on actual clinical outcomes in their hospital, Crofts and colleagues noted that the rate of obstetric brachial plexus injury fell from 7.4% in a 4-year period prior to training, to 2.3% in a 4-year period after training.⁴

Practice within your own L&D unit

The use of in situ simulation (ie, simulation within the labor and delivery unit) has two major advantages:

• It is more realistic than practicing within a lab. Systems issues, such as lack of a uniform procedure for getting help or a lack of chairs in the labor room to assist with performance of suprapubic pressure, can be identified.
• The full team, including ward clerks and other support personnel, can be part of the simulation more readily.

The box on this page provides a possible process to use in managing shoulder dystocia. If there has not been an opportunity for this training, practitioners, at the very least, should be cognizant of the steps they are going to take in managing such cases.

What should you do after primary maneuvers fail?

Try to deliver the posterior arm. Although the order of maneuvers in the proposed algorithm may vary, a recent study using a database of more than 130,000 deliveries suggests that use of posterior arm delivery after failure of primary maneuvers, such as McRoberts or suprapubic pressure, may more likely result in resolution.⁵

Start from the beginning, and try again. If the first set of maneuvers does not resolve the problem, running through them again usually leads to success. Although the risk of fetal hypoxia increases the longer it takes to resolve the dystocia, it may actually facilitate delivery because fetal tone may also decrease.

Zavanelli maneuver. In general, use of the Zavanelli maneuver with replacement of the fetal head accompanied by cesarean section is a last resort; there is a lack of data to support its use earlier in the process or more frequently. This maneuver requires reversing the cardinal movements related to head descent in order to successfully complete replacement.

Shoulder dystocia in obese patients proves more difficult

In my own experience with obese patients, suprapubic pressure is often ineffective due to the presence of a large fat pad or pannus. Use of an anterior Rubin’s maneuver to rotate the shoulders about 30° to the oblique often facilitates delivery.

Liberal use of episiotomy to facilitate posterior arm delivery or rotational maneuvers is often necessary with obese patients.

Documentation is key

Documentation of the dystocia event in the patient’s permanent record should not occur until after the care team has discussed the case. This will ensure that the maneuvers utilized and the related timing of events are recorded accurately. This is critically important should a lawsuit occur, since discrepancies or errors in charting will hamper defense of the case. A checklist, such as the one provided by the American College of Obstetricians and Gynecologists, lists key points that should be recorded and outlines important steps related to the event.⁶

We want to hear from you! Tell us what you think.

It is not uncommon to see a patient in her first trimester who is experiencing abdominal pain or vaginal bleeding or both. At my institution, we use the beta human chorionic gonadotropin (ß-hCG) value in conjunction with transvaginal ultrasonography to determine whether the pregnancy is a viable intrauterine pregnancy, a missed spontaneous abortion, or an ectopic gestation. However, even a combination of modalities can be inconclusive, necessitating repeated ß-hCG measurements and several ultrasound images. For the patient, it can provoke considerable anxiety to be told to wait and see if the pregnancy will continue.

Testing will not distinguish ectopic from intrauterine gestations

In their meta-analysis, Verhaegen and colleagues focused on a single measurement of progesterone to predict the pregnancy outcome in women who experienced pain or bleeding, or both. In early pregnancy, progesterone is produced first by the corpus luteum, then by the placenta. It stands to reason that nonviable pregnancies would have a lower level.

Although measurement of the progesterone level will not help distinguish an ectopic gestation from an intrauterine pregnancy, it does help identify nonviable pregnancy. This study found that a progesterone level below 6 ng/mL excluded a viable pregnancy in 99.2% of cases. Measuring progesterone could be very helpful when the ß-hCG level is low and ultrasound imaging is inconclusive. Currently, we tell patients under these circumstances that we need more time to sort it all out—we need to establish a trend for the ß-hCG and repeat ultrasonography. However, if we added assessment of the progesterone level and it were less than 6 ng/mL, we would be able to determine with near certainty that the pregnancy is nonviable. As a result, we could provide patients with some certainty earlier than we would otherwise be able to, even if it were not the news they had hoped to hear.

When the serum progesterone level is higher than 6 ng/mL, it doesn’t guarantee a viable pregnancy. Rather, it leaves us about where we were without it—somewhat unsure as to how things will turn out.

Testing may save money in the long run

Another advantage of adding the assessment of progesterone level may be lowered costs. If the progesterone level is less than 6 ng/mL and we can determine with almost 100% assurance when a pregnancy is nonviable, we stand to save the costs associated with additional visits, imaging, and ß-hCG testing. The authors did not address this issue, but perhaps another study will look at it more closely.

We want to hear from you! Tell us what you think.

It is not uncommon to see a patient in her first trimester who is experiencing abdominal pain or vaginal bleeding or both. At my institution, we use the beta human chorionic gonadotropin (ß-hCG) value in conjunction with transvaginal ultrasonography to determine whether the pregnancy is a viable intrauterine pregnancy, a missed spontaneous abortion, or an ectopic gestation. However, even a combination of modalities can be inconclusive, necessitating repeated ß-hCG measurements and several ultrasound images. For the patient, it can provoke considerable anxiety to be told to wait and see if the pregnancy will continue.

Testing will not distinguish ectopic from intrauterine gestations

In their meta-analysis, Verhaegen and colleagues focused on a single measurement of progesterone to predict the pregnancy outcome in women who experienced pain or bleeding, or both. In early pregnancy, progesterone is produced first by the corpus luteum, then by the placenta. It stands to reason that nonviable pregnancies would have a lower level.

Although measurement of the progesterone level will not help distinguish an ectopic gestation from an intrauterine pregnancy, it does help identify nonviable pregnancy. This study found that a progesterone level below 6 ng/mL excluded a viable pregnancy in 99.2% of cases. Measuring progesterone could be very helpful when the ß-hCG level is low and ultrasound imaging is inconclusive. Currently, we tell patients under these circumstances that we need more time to sort it all out—we need to establish a trend for the ß-hCG and repeat ultrasonography. However, if we added assessment of the progesterone level and it were less than 6 ng/mL, we would be able to determine with near certainty that the pregnancy is nonviable. As a result, we could provide patients with some certainty earlier than we would otherwise be able to, even if it were not the news they had hoped to hear.

When the serum progesterone level is higher than 6 ng/mL, it doesn’t guarantee a viable pregnancy. Rather, it leaves us about where we were without it—somewhat unsure as to how things will turn out.

Testing may save money in the long run

Another advantage of adding the assessment of progesterone level may be lowered costs. If the progesterone level is less than 6 ng/mL and we can determine with almost 100% assurance when a pregnancy is nonviable, we stand to save the costs associated with additional visits, imaging, and ß-hCG testing. The authors did not address this issue, but perhaps another study will look at it more closely.

We want to hear from you! Tell us what you think.

It is not uncommon to see a patient in her first trimester who is experiencing abdominal pain or vaginal bleeding or both. At my institution, we use the beta human chorionic gonadotropin (ß-hCG) value in conjunction with transvaginal ultrasonography to determine whether the pregnancy is a viable intrauterine pregnancy, a missed spontaneous abortion, or an ectopic gestation. However, even a combination of modalities can be inconclusive, necessitating repeated ß-hCG measurements and several ultrasound images. For the patient, it can provoke considerable anxiety to be told to wait and see if the pregnancy will continue.

Testing will not distinguish ectopic from intrauterine gestations

In their meta-analysis, Verhaegen and colleagues focused on a single measurement of progesterone to predict the pregnancy outcome in women who experienced pain or bleeding, or both. In early pregnancy, progesterone is produced first by the corpus luteum, then by the placenta. It stands to reason that nonviable pregnancies would have a lower level.

Although measurement of the progesterone level will not help distinguish an ectopic gestation from an intrauterine pregnancy, it does help identify nonviable pregnancy. This study found that a progesterone level below 6 ng/mL excluded a viable pregnancy in 99.2% of cases. Measuring progesterone could be very helpful when the ß-hCG level is low and ultrasound imaging is inconclusive. Currently, we tell patients under these circumstances that we need more time to sort it all out—we need to establish a trend for the ß-hCG and repeat ultrasonography. However, if we added assessment of the progesterone level and it were less than 6 ng/mL, we would be able to determine with near certainty that the pregnancy is nonviable. As a result, we could provide patients with some certainty earlier than we would otherwise be able to, even if it were not the news they had hoped to hear.

When the serum progesterone level is higher than 6 ng/mL, it doesn’t guarantee a viable pregnancy. Rather, it leaves us about where we were without it—somewhat unsure as to how things will turn out.

Testing may save money in the long run

Another advantage of adding the assessment of progesterone level may be lowered costs. If the progesterone level is less than 6 ng/mL and we can determine with almost 100% assurance when a pregnancy is nonviable, we stand to save the costs associated with additional visits, imaging, and ß-hCG testing. The authors did not address this issue, but perhaps another study will look at it more closely.

We want to hear from you! Tell us what you think.

The author reports no financial relationships relevant to this article.

Venous thromboembolism (VTE)—deep vein thrombosis (DVT) and pulmonary embolism (PE)—remains a major cause of morbidity and mortality in the United States, resulting in an estimated 200,000 deaths each year.¹ VTE is especially common among inpatients; hospitalization increases the risk of VTE eightfold,² and VTE is the most common preventable cause of hospital-associated deaths.^2,3 Most general medical and surgical inpatients have risk factors for VTE and, without prophylaxis, between 10% and 40% will develop DVT or PE.³ VTE is estimated to cost the US economy $4 billion annually in direct costs and substantially more in indirect costs, including lost productivity and subsequent medical expenses.⁴

There is no doubt that thromboprophylaxis is effective in preventing VTE in high-risk patients.^2,3,5-7 For this reason, the Agency for Healthcare Research and Quality ranks VTE prophylaxis as the single most important patient safety initiative deserving of more widespread implementation.⁸ The importance of this intervention has also been acknowledged by the Joint Commission,⁹ and by the Centers for Medicare & Medicaid Services, which include VTE prophylaxis in their Surgical Care Improvement Project (SCIP) quality measures that guide hospital reimbursement.¹⁰

All patients undergoing surgery (including cesarean delivery) should be considered at high risk for VTE. Additional risk factors include, among others:

• personal or family history of VTE
• known inherited or acquired thrombophilia
• obesity
• advancing age
• prolonged immobility or bed rest
• cancer.^2,3,5-7

Although there is general consensus that high-risk patients require thromboprophylaxis, exactly what form of prophylaxis to recommend remains controversial.

Graduated compression stockings may cause harm

Graduated compression stockings (also known as TED stockings) are commonly regarded as a safe and noninvasive method for preventing VTE. However, evidence in support of their efficacy is lacking. A recent consensus statement from the American College of Physicians recommended “against the use of mechanical prophylaxis with graduated compression stockings for prevention of venous thromboembolism (Grade: strong recommendation, moderate-quality evidence)” in medical and stroke patients.⁵ In support of their recommendation, the authors of this consensus statement cite a lack of evidence of benefit and significant evidence of patient harm related to skin breakdown from compression stockings. This recommendation is likely relevant also for obstetric and gynecologic patients. For this reason, I propose that the use of graduated compression stockings for DVT prophylaxis be abandoned.

Chemoprophylaxis should be routine in high-risk inpatients

VTE chemoprophylaxis with low molecular weight heparin (LMWH; eg, dalteparin or enoxaparin) or low-dose unfractionated heparin remains the most effective prophylactic measure and should be routine in all high-risk obstetric and gynecologic inpatients.^2,3,5-7 Pneumatic compression devices and chemoprophylaxis may provide synergistic protection against VTE.⁵

Cesarean delivery affects need for prophylaxis

Although pregnancy is an independent risk factor for VTE, the absolute risk of VTE in an otherwise healthy patient is only about 0.05% in both the antepartum and postpartum periods.¹¹ For this reason, routine VTE prophylaxis in pregnant patients would certainly cause more harm than good, and is not recommended. However, cesarean delivery doubles the risk of VTE, with an absolute risk in low-risk parturients of approximately 1 in 1,000 patients.¹² And 85% of fatal PE cases in pregnancy follow cesarean delivery. For these reasons, placement of pneumatic compression devices and/or administration of LMWH is recommended before cesarean delivery for all women not already receiving chemoprophylaxis.⁷

One clarification. Although the use of graduated compression stockings to prevent VTE should be abandoned entirely, there is some evidence that compression stockings with an ankle pressure of 30 to 40 mm Hg may help reduce the risk of long-term phlebitis syndrome in patients with established DVT in pregnancy.¹³ Therefore, use of compression stockings may be considered in this setting.

We want to hear from you! Tell us what you think.

The author reports no financial relationships relevant to this article.

Venous thromboembolism (VTE)—deep vein thrombosis (DVT) and pulmonary embolism (PE)—remains a major cause of morbidity and mortality in the United States, resulting in an estimated 200,000 deaths each year.¹ VTE is especially common among inpatients; hospitalization increases the risk of VTE eightfold,² and VTE is the most common preventable cause of hospital-associated deaths.^2,3 Most general medical and surgical inpatients have risk factors for VTE and, without prophylaxis, between 10% and 40% will develop DVT or PE.³ VTE is estimated to cost the US economy $4 billion annually in direct costs and substantially more in indirect costs, including lost productivity and subsequent medical expenses.⁴

There is no doubt that thromboprophylaxis is effective in preventing VTE in high-risk patients.^2,3,5-7 For this reason, the Agency for Healthcare Research and Quality ranks VTE prophylaxis as the single most important patient safety initiative deserving of more widespread implementation.⁸ The importance of this intervention has also been acknowledged by the Joint Commission,⁹ and by the Centers for Medicare & Medicaid Services, which include VTE prophylaxis in their Surgical Care Improvement Project (SCIP) quality measures that guide hospital reimbursement.¹⁰

All patients undergoing surgery (including cesarean delivery) should be considered at high risk for VTE. Additional risk factors include, among others:

• personal or family history of VTE
• known inherited or acquired thrombophilia
• obesity
• advancing age
• prolonged immobility or bed rest
• cancer.^2,3,5-7

Although there is general consensus that high-risk patients require thromboprophylaxis, exactly what form of prophylaxis to recommend remains controversial.

Graduated compression stockings may cause harm

Graduated compression stockings (also known as TED stockings) are commonly regarded as a safe and noninvasive method for preventing VTE. However, evidence in support of their efficacy is lacking. A recent consensus statement from the American College of Physicians recommended “against the use of mechanical prophylaxis with graduated compression stockings for prevention of venous thromboembolism (Grade: strong recommendation, moderate-quality evidence)” in medical and stroke patients.⁵ In support of their recommendation, the authors of this consensus statement cite a lack of evidence of benefit and significant evidence of patient harm related to skin breakdown from compression stockings. This recommendation is likely relevant also for obstetric and gynecologic patients. For this reason, I propose that the use of graduated compression stockings for DVT prophylaxis be abandoned.

Chemoprophylaxis should be routine in high-risk inpatients

VTE chemoprophylaxis with low molecular weight heparin (LMWH; eg, dalteparin or enoxaparin) or low-dose unfractionated heparin remains the most effective prophylactic measure and should be routine in all high-risk obstetric and gynecologic inpatients.^2,3,5-7 Pneumatic compression devices and chemoprophylaxis may provide synergistic protection against VTE.⁵

Cesarean delivery affects need for prophylaxis

Although pregnancy is an independent risk factor for VTE, the absolute risk of VTE in an otherwise healthy patient is only about 0.05% in both the antepartum and postpartum periods.¹¹ For this reason, routine VTE prophylaxis in pregnant patients would certainly cause more harm than good, and is not recommended. However, cesarean delivery doubles the risk of VTE, with an absolute risk in low-risk parturients of approximately 1 in 1,000 patients.¹² And 85% of fatal PE cases in pregnancy follow cesarean delivery. For these reasons, placement of pneumatic compression devices and/or administration of LMWH is recommended before cesarean delivery for all women not already receiving chemoprophylaxis.⁷

One clarification. Although the use of graduated compression stockings to prevent VTE should be abandoned entirely, there is some evidence that compression stockings with an ankle pressure of 30 to 40 mm Hg may help reduce the risk of long-term phlebitis syndrome in patients with established DVT in pregnancy.¹³ Therefore, use of compression stockings may be considered in this setting.

We want to hear from you! Tell us what you think.

The author reports no financial relationships relevant to this article.

Venous thromboembolism (VTE)—deep vein thrombosis (DVT) and pulmonary embolism (PE)—remains a major cause of morbidity and mortality in the United States, resulting in an estimated 200,000 deaths each year.¹ VTE is especially common among inpatients; hospitalization increases the risk of VTE eightfold,² and VTE is the most common preventable cause of hospital-associated deaths.^2,3 Most general medical and surgical inpatients have risk factors for VTE and, without prophylaxis, between 10% and 40% will develop DVT or PE.³ VTE is estimated to cost the US economy $4 billion annually in direct costs and substantially more in indirect costs, including lost productivity and subsequent medical expenses.⁴

There is no doubt that thromboprophylaxis is effective in preventing VTE in high-risk patients.^2,3,5-7 For this reason, the Agency for Healthcare Research and Quality ranks VTE prophylaxis as the single most important patient safety initiative deserving of more widespread implementation.⁸ The importance of this intervention has also been acknowledged by the Joint Commission,⁹ and by the Centers for Medicare & Medicaid Services, which include VTE prophylaxis in their Surgical Care Improvement Project (SCIP) quality measures that guide hospital reimbursement.¹⁰

All patients undergoing surgery (including cesarean delivery) should be considered at high risk for VTE. Additional risk factors include, among others:

• personal or family history of VTE
• known inherited or acquired thrombophilia
• obesity
• advancing age
• prolonged immobility or bed rest
• cancer.^2,3,5-7

Although there is general consensus that high-risk patients require thromboprophylaxis, exactly what form of prophylaxis to recommend remains controversial.

Graduated compression stockings may cause harm

Graduated compression stockings (also known as TED stockings) are commonly regarded as a safe and noninvasive method for preventing VTE. However, evidence in support of their efficacy is lacking. A recent consensus statement from the American College of Physicians recommended “against the use of mechanical prophylaxis with graduated compression stockings for prevention of venous thromboembolism (Grade: strong recommendation, moderate-quality evidence)” in medical and stroke patients.⁵ In support of their recommendation, the authors of this consensus statement cite a lack of evidence of benefit and significant evidence of patient harm related to skin breakdown from compression stockings. This recommendation is likely relevant also for obstetric and gynecologic patients. For this reason, I propose that the use of graduated compression stockings for DVT prophylaxis be abandoned.

Chemoprophylaxis should be routine in high-risk inpatients

VTE chemoprophylaxis with low molecular weight heparin (LMWH; eg, dalteparin or enoxaparin) or low-dose unfractionated heparin remains the most effective prophylactic measure and should be routine in all high-risk obstetric and gynecologic inpatients.^2,3,5-7 Pneumatic compression devices and chemoprophylaxis may provide synergistic protection against VTE.⁵

Cesarean delivery affects need for prophylaxis

Although pregnancy is an independent risk factor for VTE, the absolute risk of VTE in an otherwise healthy patient is only about 0.05% in both the antepartum and postpartum periods.¹¹ For this reason, routine VTE prophylaxis in pregnant patients would certainly cause more harm than good, and is not recommended. However, cesarean delivery doubles the risk of VTE, with an absolute risk in low-risk parturients of approximately 1 in 1,000 patients.¹² And 85% of fatal PE cases in pregnancy follow cesarean delivery. For these reasons, placement of pneumatic compression devices and/or administration of LMWH is recommended before cesarean delivery for all women not already receiving chemoprophylaxis.⁷

One clarification. Although the use of graduated compression stockings to prevent VTE should be abandoned entirely, there is some evidence that compression stockings with an ankle pressure of 30 to 40 mm Hg may help reduce the risk of long-term phlebitis syndrome in patients with established DVT in pregnancy.¹³ Therefore, use of compression stockings may be considered in this setting.

We want to hear from you! Tell us what you think.

The two most commonly utilized methods of skin closure after cesarean delivery are nonabsorbable metal staples and absorbable suture.¹ A number of investigators have explored these methods of closure in regard to wound complications, pain perception, patient satisfaction, and physician assessment of cosmesis.²

A recent Cochrane meta-analysis of these studies revealed that there were no significant differences between these two methods with respect to wound infection, patient satisfaction, pain perception, or physician assessment of cosmesis.² However, there was a significant difference between methods in terms of skin separation: Incisions closed with staples were almost four times as likely to be complicated by skin separation.²

Details of the trial

Participants had a viable pregnancy at 24 weeks’ gestation or beyond and were undergoing scheduled or unscheduled cesarean delivery. Of these, 198 women were randomly assigned to staples, and 200 were allocated to suture (Monocryl) for skin closure. Staples were removed 3 to 4 days after delivery for low transverse incisions and 7 to 10 days after delivery for vertical incisions.

Standardized physical examination of the wound was performed at hospital discharge (days 3–4) and 4 to 6 weeks postoperatively. The primary outcome was a composite of wound disruption or infection that occurred 4 to 6 weeks postoperatively; secondary outcomes included operative time, pain, cosmesis, and patient satisfaction with the scar.

Strengths of the trial include sample size

Of the studies that have been published to date, this trial by Figueroa and colleagues is the second largest to compare staples with suture for closure of cesarean skin incisions.

Another strength of this study is its intention-to-treat analysis and the low rate of patients who were lost to follow-up.

This study is similar to the largest study, by Basha and colleagues, that examined skin closure after cesarean, in that women undergoing cesarean delivery via vertical or low transverse incisions were allocated to closure of the skin with staples or absorbable (Monocryl) suture.³ In both studies, staples were removed 3 or 4 days after delivery, although Figueroa and colleagues specified that staples be removed on days 7 to 10 for women who had vertical incisions.³

A few weaknesses may limit generalizability of the findings

Figueroa and colleagues noted that women in their study received prophylactic antibiotics at the time of cord clamping, rather than preoperatively, although the latter approach now is considered more appropriate in terms of reducing wound morbidity.⁴

Another limitation: Enrollment was terminated early, after enrolling only approximately one-third of the intended sample size. Figueroa and colleagues explain that this decision was based on the findings of Basha and colleagues, which were published during active enrollment of the Figueroa study.³ Not only did Basha and colleagues report a higher incidence of wound complications than Figueroa and colleagues had used to calculate the required sample size, but the Basha study also concluded that sutures may be more optimal for skin closure with respect to skin separation.³

In the study by Figueroa and colleagues, the primary outcome was defined as a composite of wound disruption or infection. However, there was no specification as to length of skin dehiscence that would qualify as disruption—although the investigators did note that the difference in wound disruption remained statistically significant when analyses were limited to wounds involving disruption of more than 1 cm.

As have earlier studies, Figueroa and colleagues found that operative time was longer when sutures were used, compared with staples.

Most earlier studies that assessed cosmesis utilized the Physician Observer Scar Assessment Scale, but this study did not, so it is unclear whether the findings can be compared with prior investigations on this point.

We want to hear from you! Tell us what you think.

The two most commonly utilized methods of skin closure after cesarean delivery are nonabsorbable metal staples and absorbable suture.¹ A number of investigators have explored these methods of closure in regard to wound complications, pain perception, patient satisfaction, and physician assessment of cosmesis.²

A recent Cochrane meta-analysis of these studies revealed that there were no significant differences between these two methods with respect to wound infection, patient satisfaction, pain perception, or physician assessment of cosmesis.² However, there was a significant difference between methods in terms of skin separation: Incisions closed with staples were almost four times as likely to be complicated by skin separation.²

Details of the trial

Participants had a viable pregnancy at 24 weeks’ gestation or beyond and were undergoing scheduled or unscheduled cesarean delivery. Of these, 198 women were randomly assigned to staples, and 200 were allocated to suture (Monocryl) for skin closure. Staples were removed 3 to 4 days after delivery for low transverse incisions and 7 to 10 days after delivery for vertical incisions.

Standardized physical examination of the wound was performed at hospital discharge (days 3–4) and 4 to 6 weeks postoperatively. The primary outcome was a composite of wound disruption or infection that occurred 4 to 6 weeks postoperatively; secondary outcomes included operative time, pain, cosmesis, and patient satisfaction with the scar.

Strengths of the trial include sample size

Of the studies that have been published to date, this trial by Figueroa and colleagues is the second largest to compare staples with suture for closure of cesarean skin incisions.

Another strength of this study is its intention-to-treat analysis and the low rate of patients who were lost to follow-up.

This study is similar to the largest study, by Basha and colleagues, that examined skin closure after cesarean, in that women undergoing cesarean delivery via vertical or low transverse incisions were allocated to closure of the skin with staples or absorbable (Monocryl) suture.³ In both studies, staples were removed 3 or 4 days after delivery, although Figueroa and colleagues specified that staples be removed on days 7 to 10 for women who had vertical incisions.³

A few weaknesses may limit generalizability of the findings

Figueroa and colleagues noted that women in their study received prophylactic antibiotics at the time of cord clamping, rather than preoperatively, although the latter approach now is considered more appropriate in terms of reducing wound morbidity.⁴

Another limitation: Enrollment was terminated early, after enrolling only approximately one-third of the intended sample size. Figueroa and colleagues explain that this decision was based on the findings of Basha and colleagues, which were published during active enrollment of the Figueroa study.³ Not only did Basha and colleagues report a higher incidence of wound complications than Figueroa and colleagues had used to calculate the required sample size, but the Basha study also concluded that sutures may be more optimal for skin closure with respect to skin separation.³

In the study by Figueroa and colleagues, the primary outcome was defined as a composite of wound disruption or infection. However, there was no specification as to length of skin dehiscence that would qualify as disruption—although the investigators did note that the difference in wound disruption remained statistically significant when analyses were limited to wounds involving disruption of more than 1 cm.

As have earlier studies, Figueroa and colleagues found that operative time was longer when sutures were used, compared with staples.

Most earlier studies that assessed cosmesis utilized the Physician Observer Scar Assessment Scale, but this study did not, so it is unclear whether the findings can be compared with prior investigations on this point.

We want to hear from you! Tell us what you think.

The two most commonly utilized methods of skin closure after cesarean delivery are nonabsorbable metal staples and absorbable suture.¹ A number of investigators have explored these methods of closure in regard to wound complications, pain perception, patient satisfaction, and physician assessment of cosmesis.²

A recent Cochrane meta-analysis of these studies revealed that there were no significant differences between these two methods with respect to wound infection, patient satisfaction, pain perception, or physician assessment of cosmesis.² However, there was a significant difference between methods in terms of skin separation: Incisions closed with staples were almost four times as likely to be complicated by skin separation.²

Details of the trial

Participants had a viable pregnancy at 24 weeks’ gestation or beyond and were undergoing scheduled or unscheduled cesarean delivery. Of these, 198 women were randomly assigned to staples, and 200 were allocated to suture (Monocryl) for skin closure. Staples were removed 3 to 4 days after delivery for low transverse incisions and 7 to 10 days after delivery for vertical incisions.

Standardized physical examination of the wound was performed at hospital discharge (days 3–4) and 4 to 6 weeks postoperatively. The primary outcome was a composite of wound disruption or infection that occurred 4 to 6 weeks postoperatively; secondary outcomes included operative time, pain, cosmesis, and patient satisfaction with the scar.

Strengths of the trial include sample size

Of the studies that have been published to date, this trial by Figueroa and colleagues is the second largest to compare staples with suture for closure of cesarean skin incisions.

Another strength of this study is its intention-to-treat analysis and the low rate of patients who were lost to follow-up.

This study is similar to the largest study, by Basha and colleagues, that examined skin closure after cesarean, in that women undergoing cesarean delivery via vertical or low transverse incisions were allocated to closure of the skin with staples or absorbable (Monocryl) suture.³ In both studies, staples were removed 3 or 4 days after delivery, although Figueroa and colleagues specified that staples be removed on days 7 to 10 for women who had vertical incisions.³

A few weaknesses may limit generalizability of the findings

Figueroa and colleagues noted that women in their study received prophylactic antibiotics at the time of cord clamping, rather than preoperatively, although the latter approach now is considered more appropriate in terms of reducing wound morbidity.⁴

Another limitation: Enrollment was terminated early, after enrolling only approximately one-third of the intended sample size. Figueroa and colleagues explain that this decision was based on the findings of Basha and colleagues, which were published during active enrollment of the Figueroa study.³ Not only did Basha and colleagues report a higher incidence of wound complications than Figueroa and colleagues had used to calculate the required sample size, but the Basha study also concluded that sutures may be more optimal for skin closure with respect to skin separation.³

In the study by Figueroa and colleagues, the primary outcome was defined as a composite of wound disruption or infection. However, there was no specification as to length of skin dehiscence that would qualify as disruption—although the investigators did note that the difference in wound disruption remained statistically significant when analyses were limited to wounds involving disruption of more than 1 cm.

As have earlier studies, Figueroa and colleagues found that operative time was longer when sutures were used, compared with staples.

Most earlier studies that assessed cosmesis utilized the Physician Observer Scar Assessment Scale, but this study did not, so it is unclear whether the findings can be compared with prior investigations on this point.

We want to hear from you! Tell us what you think.