Highlights from #AAST2014 - Morbidity and Mortality of Emergency General Surgery

Former resident Allan Peetz presented his work on Emergency General Surgery.

DEFINING THE EXCESS MORBIDITY AND MORTALITY ATTRIBUTABLE TO EMERGENCY GENERAL SURGERY

Allan B. Peetz MD, Ali Salim* MD, Zara Cooper MD, Edward Kelly* MD, Reza Askari MD, Jonathan Gates MBA,MD, Gally Reznor MS, Joaquim Havens MD, Brigham and Womens Hospital

Invited Discussant: Shahid Shafi, MD

Introduction: Emergency general surgery (EGS) carries a disproportionate burden of risk from medical errors, complications and death compared to non-emergency general surgery (NEGS). Previous studies have been limited by patient and procedure heterogeneity, but suggest worse outcome due to preoperative risk factors. We hypothesize that the disproportionate morbidity and mortality in EGS patients are not fully explained by these factors but are due to the EGS itself.

Methods: We retrospectively analyzed data from patients in the American College of Surgery National Surgical Quality Improvement Program (ACS-NSQIP) database that underwent one of 14 selected procedures between 2008 and 2013. The procedures represented general and vascular surgery operations common to both emergency and elective settings including; visceral resection, abdominal wall hernia repair, ileo-mesenteric bypass, and aortic reconstruction. Patients were stratified based on emergency status. The primary outcome was death within 30 days of operation. Secondary outcomes included post-operative complications. 42 preoperative variables were analyzed from the ACS-NSQIP preoperative risk assessment which includes demographic data, functional and dependent status, smoking and alcohol history, comorbidities, presence of sepsis, acute renal failure, revascularization/amputation, recent dialysis, impaired sensorium, pneumonia, recent ventilator dependence, steroid use, bleeding disorders, preoperative blood transfusions, laboratory data, and American Society of Anesthesia classification. Additionally, wound class and 23 post-operative outcomes were analyzed. This included the ACS-NSQIP post-operative occurrences (wound, respiratory, urinary tract, central nervous system, cardiac, hematologic, and septic). A Chi-square test was used to compare categorical variables and the Wilcoxon rank sum test for continuous variables. Multivariate logistic regression analysis was performed to identify independent risk factors for mortality and complications.

Results: Of 66,665 patients, 24,068 underwent emergency procedures and 42,597 were non emergent. Death occurred in 12.5% of EGS patients and 2.7% of NEGS patients (p<.0001). Post-operative complications occurred in 48.2% of EGS patients and 27.5% of NEGS patients (p<.0001). When preoperative risk factors, type of procedure, and post-operative complications were controlled, EGS was independently associated with death (Odds Ratio (OR) 1.13 p<.0001) and complications (OR 1.09 p<.0001). EGS was also independently associated with wound (OR 1.03 p=0.07) and respiratory complications (OR 1.17 p<.0001).

Conclusion: EGS is an independent risk factor for death and post-operative complication. The disproportionate morbidity and mortality observed in EGS is independent of patient factors, type of operation, and type of post-operative complication. Research seeking to improve EGS patient outcomes should include investigating the cause of this excess burden of risk with special consideration for identifying modifiable factors.