The Effect of Immunosuppression on Emergency Colectomy Outcomes: A Nationwide Retrospective Analysis

Background The impact of immunosuppression on the outcomes of emergent surgery remains poorly described. We aimed to quantify the impact of chronic immunosuppression on outcomes of patients undergoing emergent colectomy (EC). Methods The Colectomy-Targeted ACS-NSQIP database 2012–2016 was queried for patients who underwent colectomy for an emergent indication. As per NSQIP, chronic immunosuppression was defined as the use of corticosteroid or immunosuppressant medication within the prior 30 days. Patients undergoing EC for any indication were divided into two groups: immunosuppressant use (IMS) and no immunosuppressant use (NIS). Patients were propensity-score-matched on demographics, comorbidities, preoperative laboratory values, and operative variables in a 1:1 ratio to control for confounding factors. The primary outcome was 30-day mortality. Secondary outcomes included overall 30-day morbidity, individual postoperative complications (e.g., wound dehiscence, anastomotic leak, and sepsis), and hospital length of stay. Results Out of a total of 130,963 patients, 17,707 patients underwent an EC, of which 15,422 were NIS and 2285 were IMS. Totally, 2882 patients were matched (1441 NIS; 1441 IMS). The median age was 66 [IQR 56–76]; 56.8% were female; patients more frequently underwent a diversion procedure rather than primary anastomosis (68.4% vs 31.6%). Overall, as compared to NIS, IMS patients had higher 30-day mortality (21.4% vs 18.5%, p = 0.045) and overall morbidity (79.7% vs 75.7%, p = 0.011). Particularly, IMS patients had increased rates of unplanned intubations (11.5% vs 7.9%, p = 0.001), wound dehiscence (5.7% vs 3.5%, p = 0.006), progressive renal insufficiency 2.2% vs 1.2%, p = 0.042), pneumonia (12.6% vs 10.0%, p = 0.029), and longer median hospital length of stay [12.0 (8.0–21.0) vs 11.0 (7.0–19.0), p < 0.001] as compared to NIS patients. Conclusions Chronic immunosuppression is independently associated with a significant and quantifiable increase in 30-day mortality and complications for patients undergoing EC. Our results provide the emergency surgeon with quantifiable risk estimates that can help guide better patient counseling while setting reasonable expectations.