Faculty Bibliography

BACKGROUND:Patients with severe, complicated Clostridium difficile infection (CDI) may ultimately require a colectomy. Although associated with high morbidity and mortality, a total colectomy has been the mainstay of surgical treatment. However, small studies have suggested partial colectomy may provide equivalent outcomes. We compared the outcomes of partial and total colectomy for CDI in a nationwide database. STUDY DESIGN/METHODS:We performed a retrospective study using the American College of Surgeons National Surgical Quality Improvement Project (NSQIP). Patients with a primary diagnosis of Clostridium difficile colitis from 2007 to 2015, who underwent a total abdominal or partial colectomy, were analyzed. Postoperative mortality rate, complications, and length of stay were evaluated. Logistic regression controlling for patient and clinical factors evaluated the impact of type of operation performed. RESULTS:There were 733 colectomies for CDI, of which 151 (20.6%) were partial colectomies. Patients with a partial colectomy had a slightly higher 30-day mortality rate (37.1%) compared with total abdominal colectomy patients (34.7%, p = 0.58). However, logistic regression controlling for patient factors demonstrated no statistically significant difference for partial colectomy in 30-day mortality (odds ratio [OR] 1.21, 95% CI 0.76 to 1.96) or complication rate (OR 0.92, 95% CI 0.51 to 1.62) compared with total colectomy. There was no difference in days to surgery (4.6 partial vs 5.0 total, p = 0.70). Total abdominal colectomy trended toward a longer postoperative stay (18.0 vs 15.1 days for partial, p = 0.08). CONCLUSIONS:In a national database, a significant percentage of operations for CDI are partial colectomies. There were no significant differences found in mortality or complications between partial and total colectomy for severe complicated CDI.

BACKGROUND:Surgical futility is poorly defined. However, there are patients with extremely high preoperative risk who still undergo surgery and ultimately die, suggesting futile care. To further explore surgical futility, we examined the incidence and factors associated with extreme-risk patients undergoing major emergency general surgery with early death. METHODS:The American College of Surgeons National Surgical Quality Improvement Program database was reviewed for all adults undergoing colectomy, small bowel resection, control of bleeding ulcer, lysis of adhesion, and exploratory laparotomy between 2007 and 2015. Extreme-risk was defined as having an estimated mortality risk ≥75% using the National Surgical Quality Improvement Program mortality-risk calculator. Futile care was defined as extreme-risk patients who died within 48 hours of an operation. The incidence of, and clinical factors associated with, futile surgery were identified. RESULTS:Of 94,350 emergency general surgery patients, 1.9% were extreme-risk. Among extreme-risk patients, 30-day mortality was 71.2%; 31.6% of extreme-risk patients died within 48 hours, representing futile care. Only 5.5% of extreme-risk patients were discharged home. Patients who were >80 years (odds ratio [OR] 6.25 vs 40-64; 95% confidence interval [CI], 4.51-8.66), septic (OR 4.63; 95% CI, 3.38-6.34), or had a dependent functional status (OR 2.50 vs independent; 95% CI, 1.83-3.43]) had higher odds of having a futile operation. CONCLUSION:A significant number of emergency general surgery operations were on extreme-risk patients who suffered early death, which may indicate futile care. Surgeons face numerous conflicting pressures when asked to perform potentially futile surgery. Additional research in the decision-making process in these cases is needed to understand why surgeons operate in such dire circumstances and whether they should.

OBJECTIVE:Medical students' abilities to predict postoperative complications and death are unknown. We hypothesize that medical students will lack confidence in determining surgical risk and will significantly overestimate surgical risk for post-operative morbidities and mortality. DESIGN/METHODS:Participants were invited to participate in an electronic, anonymous survey to assess their ability to predict surgical risk. The survey presented 7 complex clinical scenarios representative of a diverse general surgery practice. Participants were asked to assess the likelihood of different morbidities and mortality on a 0-100% scale, and predictions were compared to the ACS NSQIP risk calculator. SETTING/METHODS:Yale School of Medicine, New Haven, Connecticut; Tertiary medical center PARTICIPANTS: Third year medical students on their surgery clerkship as well as general surgery residents were invited to participate. RESULTS:Most students were not confident about predicting postoperative complications (83.3%) or mortality (70.8%). Most students did not feel that the surgery clerkship adequately prepared them to assess surgical risk (69.6%). When compared to surgical residents for most presented cases (57% of cases), students and residents similarly overestimated postoperative morbidities and mortality. Estimates varied significantly, with wide 95% confidence intervals. Only 17% of NSQIP predicted estimates fell within the 95% confidence intervals. CONCLUSIONS:Medical students overestimate morbidity and mortality following surgery in complex patients. Additionally, they lack confidence in their ability to predict surgical complications. A formal curriculum for risk prediction is needed for medical students.

BACKGROUND:The number of patients undergoing preoperative risk stratification in the United States is expected to increase as the population ages. A large percentage of patients undergo some form of preoperative testing, and society guidelines suggest that up to 50% of the testing in lower risk surgical subgroups is unnecessary. The Revised Cardiac Risk Index and the risk calculator of the American College of Surgeons National Surgical Quality Improvement Program are widely used tools as the first step of preoperative cardiac evaluation. The Revised Cardiac Risk Index was developed to fill a need for objective perioperative cardiac risk evaluation. Despite the ease of use of Revised Cardiac Risk Index, it is uncertain if the stratification is accurate for surgical patients because its accuracy in large surgical samples has not been tested. With the National Surgical Quality Improvement Program risk calculator having excellent accuracy in estimating cardiac complications (area under the receiver operating characteristic 0.895), a unique opportunity to test the predictive accuracy of postsurgical cardiac events became available. The purpose of this study is to determine the accuracy of the Revised Cardiac Risk Index for predicting cardiovascular complications after adhesiolysis for small bowel obstruction. METHODS:From 2005 to 2015, 34,032 cases of open or laparoscopic adhesiolysis (Current Procedural Terminology codes 44005 and 44180) for small bowel obstruction (International Classification of Diseases, 10th edition [ICD-10]) were analyzed using the National Surgical Quality Improvement Program dataset. Revised Cardiac Risk Index estimates were calculated for each case and compared to reported cardiovascular complications (myocardial infarction or cardiac arrest) using univariable logistic regression. Overall predictive accuracy was assessed by measuring model discrimination (area under the receiver operating characteristic) and model calibration (Hosmer-Lemeshow chi-squared statistics). RESULTS:Although the Revised Cardiac Risk Index predicted cardiovascular complications with an odds ratio of 2.3 and a 95% confidence interval of 1.9 to 2.8 (P < .001) and the Hosmer-Lemeshow chi-square was significant (0.22, P = 0.64), the area under the receiver operating characteristic was poor (0.63, 95% confidence interval 0.59-0.67). CONCLUSION:Despite its relative simplicity, the Revised Cardiac Risk Index performed poorly as a predictor of cardiovascular complications after adhesiolysis for small bowel obstruction. These findings question the utility of the Revised Cardiac Risk Index in this patient population. Future studies should aim to develop models that are computationally simple while retaining predictive accuracy.

BACKGROUND:Current guidelines for small bowel obstruction (SBO) recommend a limited trial of nonoperative management of no more than 3-5 d. For patients requiring surgery, it is uncertain if sociodemographic factors are associated with disparities in the duration of the trial of nonoperative therapy. METHODS:The Healthcare Cost and Utilization Project National Inpatient Sample from 2012 to 2014 was queried for discharges with a primary diagnosis of SBO. Primary outcomes of interest were the effects of sociodemographic factors, including race, insurance status, and income on the rate of receiving any operative management for SBO, and subsequently, among patients managed surgically, the risk of operative delay, defined as operative management ≥ 5 d after admission. We did this by using logistic hierarchical generalized linear models, accounting for hospital clustering and adjusted for sex, age, comorbidity, and hospital factors. RESULTS:Of the 589,850 admissions for SBO between 2012 and 2014, 22.0% underwent operations. Overall, 26.2% were non-White, including 12.2% Black and 8.6% Hispanic patients, and the majority (56.0%) had Medicare insurance coverage. Income quartiles were evenly distributed across the overall study population. In adjusted logistic regression, operative delay was associated with increased odds of in-hospital mortality (odds ratio 1.30 95% confidence interval [1.10, 1.54]). Adjusted for patient and hospital factors, Black patients were significantly more likely to receive operations for SBO, whereas Medicaid and Medicare patients were significantly less likely. However, Black, Medicaid, and Medicare patients who were managed operatively were significantly more likely to have an operative delay of 5 or more d. There was no significant association between income and operative management in adjusted regression models. CONCLUSIONS:Significant disparities in the operative management were based on race and insurance status. Further research is warranted to understand the causes of, and solutions to, these sociodemographic disparities in care.

BACKGROUND:The Model for End-Stage Liver Disease (MELD) score and ascites correlate with surgical morbidity and mortality. However, the MELD score does not account for ascites. We sought to evaluate whether the MELD score accurately risk stratifies patients with ascites. METHODS:We analyzed the American College of Surgeons National Surgical Quality Improvement Program (2005-2014) to examine the risk-adjusted morbidity and mortality of cirrhotic patients with and without ascites undergoing colectomy for diverticulitis. Patients were stratified by MELD score, and the presence of ascites and outcomes were compared between patients with and without ascites to the reference group of low MELD and no ascites. Multivariable logistic regression was used to control for demographic factors and comorbidities. RESULTS:A total of 16,877 colectomies were analyzed. For each MELD stratum, patients with ascites have increased risk of complications compared to those without ascites (P < 0.05 unless indicated): low MELD ascites OR 1.13, P = 0.69, moderate MELD no ascites OR 1.37, moderate MELD ascites OR 2.06, high MELD no ascites OR 1.93, and high MELD ascites OR 3.54. These trends hold true for mortality: low MELD ascites OR 2.91, P = 0.063, moderate MELD no ascites OR 1.47, moderate MELD ascites OR 5.62, high MELD no ascites OR 3.04, and high MELD ascites OR 9.91. CONCLUSION:Ascites predicts an increased risk for postoperative morbidity and mortality for cirrhotic patients undergoing colectomy for all MELD classifications. These findings suggest that the MELD score significantly underestimates postoperative risk as it does not account for ascites.

BACKGROUND:Small bowel obstruction is common and often requires surgical management. Simple preoperative models are lacking to predict post-operative complications after surgical management of adhesive small bowel obstruction. METHODS:We retrospectively analyzed data from 15,036 patients who underwent open lysis of adhesions for small bowel obstruction from 2005 to 2013 using the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database. Predictors of post-operative complications were identified using logistic regression. Predictive models were compared using areas under the receiver operating characteristic curves (AUROC). RESULTS:A three-parameter model was constructed, termed FAS: Functional status, American Society of Anesthesiologists (ASA) classification, and prior Sepsis. FAS predicted post-operative complications with odds ratio (OR) 1.11, 95% CI (1.10, 1.12), P < 0.001 and AUROC of 0.69, 95% CI (0.67, 0.70). CONCLUSIONS:FAS predicts post-operative complications after open lysis of adhesions using three readily available clinical parameters.

BACKGROUND:Factors associated with postoperative ileus and increased resource utilization for patients who undergo operative intervention for small-bowel obstruction are not extensively studied. We evaluated the association between total duration of preoperative symptoms and postoperative outcomes in this population. MATERIALS AND METHODS:We performed a retrospective review of patients who underwent surgery for small-bowel obstruction (2013-2016). Clinical data were recorded. Total duration of preoperative symptoms included all symptoms before operation, including those before presentation. Primary endpoint was time to tolerance of diet. Secondary endpoints included length of stay, total parenteral nutrition use, and intensive care unit admission. Association between variables and outcomes was analyzed using univariable analysis, multivariable Poisson modeling, and t-test to compare groups. RESULTS:Sixty-seven patients were included. On presentation, the median duration of symptoms before hospitalization was 2 d (range 0-18 d). Total duration of preoperative symptoms was associated with time to tolerance of diet on univariable analysis (Pearson's moment correlation: 0.28, 95% confidence interval: 0.028-0.5, P = 0.03). On multivariable analysis, ascites was correlated with time to tolerance of diet (P < 0.01), but total duration of preoperative symptoms (P = 0.07) was not. Length of stay (Pearson's correlation: 0.24, 95% confidence interval: -0.02 to 0.47, P = 0.07) was not statistically different in patients with longer preoperative symptoms. Symptom duration was not statistically associated with intensive care unit (P = 0.18) or total parenteral nutrition (P = 0.3) utilization. CONCLUSIONS:Our findings demonstrate that preoperative ascites correlated with increased time to tolerance of diet, and duration of preoperative symptoms may be related to postoperative ileus.

BACKGROUND:The assessment of postoperative morbidity and mortality is difficult particularly for complex patients. We hypothesize that surgeons overestimate the risk for complications and death after surgery in complex surgical patients. MATERIALS AND METHODS:General surgery residents and attending surgeons estimated the likelihood of any morbidity, mortality, surgical site infection, pneumonia, and cardiac complications for seven complex scenarios. Responses were compared with the American College of Surgeons National Surgical Quality Improvement Project Surgical Risk Calculator. RESULTS:From 101 residents and 48 attending surgeons, overall response rate was 61.7%. For all seven clinical scenarios, there was no difference between resident and attending predictions of morbidity or mortality, with significant variation in estimates among participants. Mean percentages of the estimates were 25.8%-30% over the National Surgical Quality Improvement Project estimates for morbidity and mortality. CONCLUSIONS:General surgery residents and attending surgeons overestimated risks in complex surgical patients. These results demonstrate broad variance in and near universal overestimation of predicted surgical risk when compared with national, risk-adjusted models.

BACKGROUND:Ascites and the Model for End-Stage Liver Disease score have both been shown to independently correlate with surgical morbidity and mortality. We evaluated if incorporating the presence of ascites changed postoperative risk as assessed by the Model for End-Stage Liver Disease score. METHODS:Data originated from the National Surgical Quality Improvement Program database from 2005-2014. Patients undergoing hernia repair, adhesiolysis, and cholecystectomy were included. Univariate analysis and logistic regression stratified by Model for End-Stage Liver Disease score and presence of ascites was performed. RESULTS:A total of 30,391 patients were analyzed. When compared to low Model for End-Stage Liver Disease stratum without ascites, the presence of ascites predicted increased risk for complications (low Model for End-Stage Liver Disease with ascites odds ratio 3.22, 95% confidence interval [2.00-5.18], moderate Model for End-Stage Liver Disease with ascites odds ratio 3.70, 95% confidence interval [2.64-5.19], high Model for End-Stage Liver Disease with ascites odds ratio 6.38, 95% confidence interval [4.39-9.26]). These findings hold true for mortality as well (low Model for End-Stage Liver Disease with ascites odds ratio 9.40 95% confidence interval [3.53-25.01], moderate Model for End-Stage Liver Disease with ascites odds ratio 15.24 95% confidence interval [8.17-28.45], high Model for End-Stage Liver Disease with ascites odds ratio 28.56 95% confidence interval [15.43-52.88]). CONCLUSIONS:Ascites increased the risk of morbidity and mortality across multiple general surgery operations. Model for End-Stage Liver Disease may underestimate surgical risk in patients with ascites. Predictive models inclusive of ascites may more accurately predict the perioperative risk of these complex patients.