Aaron S. Rickles

Tobacco Smoking and Postoperative Outcomes After Colorectal Surgery.

Objective: The aim of this study was to delineate the impact of smoking on postoperative outcomes after colorectal resection for malignant and benign processes. Background: Studies to date have implicated smoking as a risk factor for increased postoperative complications. However, there is a paucity of data on the effects of smoking after colorectal surgery and in particular for malignant compared with benign processes. Methods: The American College of Surgeons National Surgical Quality Improvement Program (2005–2010) database was queried for patients undergoing elective major colorectal resection for colorectal cancer, diverticular disease, or inflammatory bowel disease. Risk-adjusted 30-day outcomes were assessed and compared between patient cohorts identified as never-smokers, ex-smokers, and current smokers. Primary outcomes of incisional infections, infectious and major complications, and mortality were evaluated using regression modeling adjusting for patient characteristics and comorbidities. Results: A total of 47,574 patients were identified, of which 26,333 had surgery for colorectal cancer, 14,019 for diverticular disease, and 7222 for inflammatory bowel disease. More than 60% of patients had never smoked, 20.4% were current smokers, and 19.2% were ex-smokers. After adjustment, current smokers were at a significantly increased risk of postoperative morbidity [odds ratio (OR), 1.3; 95% confidence interval (CI), 1.21–1.40] and mortality (OR, 1.5; 95% CI, 1.11–1.94) after colorectal surgery. This finding persisted across malignant and benign diagnoses and also demonstrated a significant dose-dependent effect when stratifying by pack-years of smoking. Conclusions: Smoking increases the risk of complications after all types of major colorectal surgery, with the greatest risk apparent for current smokers. A concerted effort should be made toward promoting smoking cessation in all patients scheduled for elective colorectal surgery.

Resident involvement is associated with worse outcomes after major lower extremity amputation

BACKGROUND Despite the recent major changes in vascular and general surgery training, there has been a paucity of literature examining the effect of these changes on training and surgical outcomes. Amputations represent a common cross-section in core competencies for general surgery and vascular surgery trainees. This study evaluates the effect of trainee participation on outcomes after above-knee and below-knee amputations. METHODS The American College of Surgeons-National Surgical Quality Improvement Program (NSQIP) database (2005 to 2010) was queried using Current Procedural Terminology codes (American Medical Association, Chicago, Ill) for below-knee amputation (27880, 27882) and above knee-amputation (27590, 27592). Resident involvement was defined using the NSQIP variable and was narrowed to postgraduate year 1 to 5. Variables associated with resident involvement were identified, and mortality, morbidity, intraoperative transfusion, and operative time (75th percentile vs the bottom three quartiles) were evaluated as distinct categoric end points in logistic regression. Included in the model were variables with a P value <.1 on χ(2) or independent t-test, as appropriate. Significance was defined at P < .05. RESULTS Residents were involved in 6587 of 11,038 amputations (62%). After adjustment for preoperative and intraoperative factors on logistic regression, there was a significant increase in major morbidity (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.14-1.42; P < .001), intraoperative transfusion (OR, 1.78; 95% CI, 1.50-2.11; P < .001), and operative time (OR, 1.64 95% CI, 1.46-1.84; P < .001) in resident cases. CONCLUSIONS Resident involvement was associated with increased odds of major morbidity after amputation and also with increased operative time and risk for intraoperative transfusions.

Closure of defunctioning loop ileostomy is associated with considerable morbidity.

Aim  An elective defunctioning ileostomy is commonly employed to attenuate the morbidity that may arise from distal anastomotic leakage. The magnitude of risk associated with subsequent ileostomy closure is difficult to estimate as many of the data arise from small series. This study looked at the rate of complications and predictive factors in a large series of patients.

Outcomes Associated With Resident Involvement in Partial Colectomy

BACKGROUND: Surgical cases that include trainees are associated with worse outcomes in comparison with those that include attending surgeons alone. OBJECTIVE: This study aimed to identify whether resident involvement in partial colectomy was associated with worse outcomes when evaluated by surgical approach and resident experience. DESIGN: This is a retrospective study using the National Surgical Quality Improvement Program database. SETTINGS: This study evaluates cases included in the National Surgical Quality Improvement Program database. PATIENTS: All patients were included who underwent partial colectomy including both open and laparoscopic approaches. INTERVENTIONS: Residents were involved. MAIN OUTCOME MEASURES: The primary outcome measures were the association of resident involvement and major complication events, minor complication events, unplanned return to operating room, and operative time. RESULTS: Cases with residents were associated with major complications (OR 1.18, CI 1.09–1.27, p < 0.001) on multivariate analysis. However, after including operative time in the model only open cases involving fifth year residents were still associated with major complications (OR 1.13, p = 0.037). Resident involvement was associated with increased likelihood of minor complications (OR 1.3, p < 0.001) and an increased risk of unplanned return to the operating room (OR 1.20, p < 0.001). Operative time was longer for cases with residents on average by 33.7 minutes and 27 minutes for open and laparoscopic cases. LIMITATIONS: This study was limited by its retrospective design and lack of data on teachings status, case complexity, and intraoperative evaluation of technique. CONCLUSIONS: Resident involvement in partial colectomies is associated with an increased major complications, minor complications, likelihood of return to the operating room, and operative time.

High rate of positive circumferential resection margins following rectal cancer surgery a call to action

Objectives : To identify predictors of positive circumferential resection margin following rectal cancer resection in the United States. Background: Positive circumferential resection margin is associated with a high rate of local recurrence and poor morbidity and mortality for rectal cancer patients. Prior study has shown poor compliance with national rectal cancer guidelines, but whether this finding is reflected in patient outcomes has yet to be shown. Methods: Patients who underwent resection for stage I-III rectal cancer were identified from the 2010–2011 National Cancer Database. The primary outcome was a positive circumferential resection margin. The relationship between patient, hospital, tumor, and treatment-related characteristics was analyzed using bivariate and multivariate analysis. Results: A positive circumferential resection margin was noted in 2859 (17.2%) of the 16,619 patients included. Facility location, clinical T and N stage, histologic type, tumor size, tumor grade, lymphovascular invasion, perineural invasion, type of operation, and operative approach were significant predictors of positive circumferential resection margin on multivariable analysis. Total proctectomy had nearly a 30% increased risk of positive margin compared with partial proctectomy (OR 1.293, 95%CI 1.185–1.411) and a laparoscopic approach had nearly 22% less risk of a positive circumferential resection margin compared with an open approach (OR 0.882, 95%CI 0.790–0.985). Conclusions: Despite advances in surgical technique and multimodality therapy, rates of positive circumferential resection margin remain high in the United States. Several tumor and treatment characteristics were identified as independent risk factors, and advances in rectal cancer care are necessary to approach the outcomes seen in other countries.

Risk score for unplanned vascular readmissions

OBJECTIVE Vascular surgery patients have high readmission rates, and identification of high-risk groups that may be amenable to targeted interventions is an important strategy for readmission prevention. This study aimed to determine predictors of unplanned readmission and develop a risk score for predicting readmissions after vascular surgery. METHODS The National Surgical Quality Improvement Program database for 2011 was queried for major vascular surgical procedures. The primary end point was unplanned 30-day readmissions. The data were randomly split into two-thirds for development and one-third for validation. Multivariable logistic regression was used to create and validate a point score system to predict unplanned readmissions. RESULTS Overall, 24,929 patients were included, with 2507 readmissions (10.1%). A point-based scoring system was developed with the use of factors predictive for readmission, including procedure type; discharge destination; race; non-elective presentation; pulmonary, renal, and cardiac comorbidities; diabetes; steroid use; hypoalbuminemia; anemia; venothromboembolism before discharge; graft failure before discharge; and bleeding disorder. The point score stratified patients into 3 groups: low risk (0-3 points) with a readmission rate of 5.4%, moderate risk (4-7 points) with a readmission rate of 8.6%, and high risk (≥ 8 points) with a readmission rate of 16.4%. The model had a C-statistic = 0.67. CONCLUSIONS Through the use of patient, operative, and predischarge events, this novel vascular surgery-specific readmission score accurately identified patients at high risk for 30-day unplanned readmission. This model could help direct discharge and home health care resources to patients at high risk, ultimately reducing readmissions and improving efficiency.

Perioperative pleiotropic statin effects in general surgery

BACKGROUND Evidence suggests that statins may decrease inflammation, airway hyperreactivity, and hypercoagulability while improving revascularization mediated by cholesterol-independent pathways. This study evaluated whether the preoperative use of statins is associated with decreased postoperative major noncardiac complications in noncardiac procedures. STUDY DESIGN This was a single-institution study of noncardiac operations performed from 2005 to 2010. The use of statins was identified from electronic medical records and merged with local National Surgical Quality Improvement Program data. Preoperative statin exposure was defined as statin use before operation, as documented by admission medication reconciliation and outpatient or pharmacy records. The primary end point was major noncardiac complications, and secondary end points included respiratory, infectious (sepsis and organ space infection) and complications of venous thromboembolism (VTE). Multivariable logistic regression was performed for each end point while we controlled for clinical covariates meeting P < .10 on bivariate analysis. RESULTS Preoperative statin use was present in 10.5% (n = 814) of 7,777 total cases. Procedure type included general operation (n = 2,605, 33.5%), breast/endocrine (n = 739, 9.5%), colorectal (n = 1,533, 19.7%), hepatobiliary/pancreatic (n = 397, 5.1%), orthopedic (n = 205, 2.6%), skin/ear-nose- throat (145, 1.9%), thoracic (n = 53, 0.7%), upper gastrointestinal (n = 651, 8.4%), and vascular cases (1,449, 18.6%). On multivariable analysis, the use of statins was associated with decreased major, noncardiac complications (odds ratio [OR] 0.62, 95% confidence interval [95% CI] 0.49-0.92, P < .001), respiratory complications (OR 0.63, 95% CI 0.50-0.79, P = .017), VTE (OR 0.41, 95% CI 0.18-0.98, P = .044), and infectious complications (OR 0.65, 95% CI 0.45-0.94, P = .023). CONCLUSION The preoperative use of statins is independently associated with decreased risk of major complications. This effect is likely driven by reduction in respiratory, VTE, and infectious complication rates. These results warrant future clinical trials to assess the perioperative benefit of statin use in noncardiac procedures.

Visceral obesity, not elevated BMI, is strongly associated with incisional hernia after colorectal surgery.

BACKGROUND: High BMI is often used as a proxy for obesity and has been considered a risk factor for the development of an incisional hernia after abdominal surgery. However, BMI does not accurately reflect fat distribution. OBJECTIVE: The purpose of this work was to investigate the relationship among different obesity measurements and the risk of incisional hernia. DESIGN: This was a retrospective cohort study. SETTINGS: The study included a single academic institution in New York from 2003 to 2010. PATIENTS: The study consists of 193 patients who underwent colorectal cancer resection. MAIN OUTCOME MEASURES: Preoperative CT scans were used to measure visceral fat volume, subcutaneous fat volume, total fat volume, and waist circumference. A diagnosis of incisional hernia was made either through physical examination in medical chart documentation or CT scan. RESULTS: Forty-one patients (21.2%) developed an incisional hernia. The median time to hernia was 12.4 months. After adjusting for patient and surgical characteristics using Cox regression analysis, visceral obesity (HR 2.04, 95% CI 1.07–3.91) and history of an inguinal hernia (HR 2.40, 95% CI 1.09–5.25) were significant risk factors for incisional hernia. Laparoscopic resection using a transverse extraction site led to a >75% reduction in the risk of incisional hernia (HR 0.23, 95% CI 0.07–0.76). BMI > 30 kg/m2 was not significantly associated with incisional hernia development. LIMITATIONS: Limitations include the retrospective design without standardized follow-up to detect hernias and the small sample size attributed to inadequate or unavailable CT scans. CONCLUSIONS: Visceral obesity, history of inguinal hernia, and location of specimen extraction site are significantly associated with the development of an incisional hernia, whereas BMI is poorly associated with hernia development. These findings suggest that a lateral transverse location is the incision site of choice and that new strategies, such as prophylactic mesh placement, should be considered in viscerally obese patients.

Risk Factors for Postdischarge Venothromboembolism After Colorectal Resection.

BACKGROUND: Current guidelines recommend extended-duration thromboprophylaxis for all abdominal oncologic resections. However, other high-risk patients may benefit from extended thromboprophylaxis. OBJECTIVE: The purpose of this study was to identify risk factors for postdischarge venothromboembolism after colorectal procedures. DESIGN: This was a retrospective cohort study. DATA SOURCES: The New York Statewide Planning and Research Cooperative System database (2005–2013) was the data source for this study. STUDY SELECTION: Colon and rectal resections were evaluated. Cases with in-hospital mortality or length of stay ≥30 days were excluded. MAIN OUTCOME MEASURES: Postdischarge venothromboembolism was defined at 30-days after the procedure requiring representation to the emergency department or hospital admission with a new diagnosis of venothromboembolism using International Classification of Diseases, Ninth Revision, codes. Factors associated with postdischarge venothromboembolism were then evaluated using a hierarchical bivariate analysis. A hierarchical mixed-effects model was created using a manual stepwise approach assessing variables meeting p < 0.1 on bivariate analysis. RESULTS: Among 128,163 patients, postdischarge venothromboembolism occurred in 0.7% (n = 789) of the population. Multiple factors were associated with postdischarge venothromboembolism on bivariate analysis. On multivariable analysis, benign conditions requiring operative intervention remained at high risk, with ulcerative colitis imparting an 93% increased odds when compared with other resections (OR, 1.93 (95% CI: 1.30–2.86); p = 0.001). Advanced malignancies (stages III and IV) were associated with increased postdischarge venothromboembolism risk, whereas stage I and II malignancies were not. The only protective factor was a laparoscopic procedure (OR, 0.80 (95% CI: 0.67–0.95); p = 0.010). There was no significant difference in procedure type after controlling for primary diagnosis. LIMITATIONS: This was a retrospective analysis of administrative data with inherent limitations. Only patients who presented with postdischarge venothromboembolism to a hospital within New York State were captured. CONCLUSIONS: This study identifies risk factors for postdischarge venothromboembolism and suggests that ulcerative colitis increases risk for postdischarge venothromboembolism whereas Crohn’s disease does not. Ulcerative colitis postdischarge venothromboembolism rates exceeded even those of malignancy, suggesting that a future study is necessary to determine the efficacy of extended duration thromboprophylaxis in high-risk benign conditions, such as ulcerative colitis.

202 Risk Factors Associated With 30-Day Readmissions in Major Gastrointestinal Resections

PURPOSE: Preventable readmissions represent a major burden on the health care system and by risk stratifying patients resources can be directed to prevent these costly complications. This study examines patient characteristics, surgical factors, and postoperative complications associated with 30-day readmissions in gastrointestinal (GI) resections. METHODS: Inpatients undergoing major GI surgery were selected from the 2011 ACS National Surgical Quality Improvement Program prospectively collected database. Procedures were classified into esophageal, gastric, small bowel, large bowel, liver, and pancreatic resections using Common Procedural Terminology codes. Postoperative complications were divided into preand post-discharge groups by comparing time to complication and discharge. Operative times were grouped by 75th percentile(./=4 hours). Univariate analysis using Chi-square, Mann Whitney-U, and Students T-test were used to compare patient comorbidities, surgical characteristics, and postoperative complications with 30-day unplanned readmission rates. Factors with a p,0.1 were included in multivariate logistic regression. Odds ratios(OR) and 95% confidence intervals(CI) are reported and p-value ,0.05 was considered statistically significant. RESULTS: For 43,894 patients undergoing GI resection, the overall 30-day unplanned readmission rate was 12.0% ranging from 11.4% for colorectal resections to 15.7% for pancreatic resections. Median postoperative length of stay was longer in the readmission group (7 vs. 6 days p,0.0001). Major predictors of 30-day readmissions included pre-discharge major complications (OR=1.28; CI: 1.14,1.44, p,0.0001), preoperative steroid use (OR=1.62; CI: 1.39,1.89, p,0.0001), operative time ./=4 hours (OR= 1.61; CI: 1.45,1.78, p,0.0001) and discharge to a facility other than home (OR=1.48; CI: 1.28,1.70, p,0.0001). Other factors associated with increased readmission included dependent functional status, open surgery, pulmonary comorbidity, neurologic comorbidity, higher ASA score, diabetes, and preoperative anemia(table 1). Post-discharge major and minor complications were highly correlated with 30-day readmission rates (OR=59.3; CI: 52.2,67.3, p,0.0001 and OR=6.3; 95%CI: 5.8,6.9, p,0.0001) and not included in the final model. CONCLUSIONS: Unplanned 30-day readmissions represent a major medical and financial concern, but some may be foreseeable and thus preventable. Although previous studies have identified major complications as a strong risk factor for readmissions, this might represent an overestimate of the risk due to confounding by including post-discharge complications that may in fact cause, not predict, readmissions. This model provides insight into factors that could inform resource utilization and post-operative care to help prevent readmissions in select high-risk GI surgical patients. Table 1: Factors associated with unplanned 30-day readmissions following GI resection.