Risk Factors for Post-Operative Sepsis and Septic Shock in Patients Undergoing Emergency Surgery

Background: Sepsis after emergency surgery is associated with a higher mortality rate than elective surgery, and total hospital costs increase by 2.3 times. This study aimed to identify risk factors for post-operative sepsis or septic shock in patients undergoing emergency surgery. Methods: A retrospective cohort analysis was performed using the National Surgical Quality Improvement Program (NSQIP) by identifying patients undergoing emergency surgery between 2012 and 2015 and comparing those who developed post-operative sepsis or septic shock (S/SS) with those who did not. Patients with pre-operative sepsis or septic shock were excluded. Multiple logistic regression was used to identify risk factors for the development of S/SS in patients undergoing non-elective surgery. Results: Of 122,281 patients who met the inclusion criteria, 2,399 (2%) developed S/SS. Risk factors for S/SS were American Society of Anesthesiologists Physical Status (ASA PS) class 2 or higher (odds ratio [OR] 2.57; 95% confidence interval [CI] 2.19–3.02; p < 0.0001), totally dependent (OR 2.00, 95% CI 1.38–2.83; p = 0.00021) or partially dependent (OR 1.62, 95% CI 1.35–2.00; p < 0.0001) functional status, and male gender (OR 1.31; 95% CI 1.18–1.45; p < 0.0001). Compared with colorectal procedures, patients undergoing pancreatic (OR 2.33, CI 1.40–3.87; p = 0.00108) and small intestine (OR 1.27; CI 1.12–1.44; p = 0.00015) surgery were more likely to develop S/SS. Patients undergoing biliary surgery (OR 0.38; CI 0.30–0.48; p < 0.0001) were less likely to develop S/SS. Conclusions: Risk factors for the development of sepsis or septic shock are ASA PS class 2 or higher, partially or totally dependent functional status, and male gender. Emergency pancreatic or small intestinal procedures may confer a higher risk. Greater vigilance and early post-operative screening may be of benefit in patients with these risk factors.