Non-Gastrointestinal Complications and Short-Term Outcomes in Patients With Anastomotic Leak After Colon Resection: A Propensity Matched Analysis of American College of Surgeons National Surgical Quality Improvement Program Database

Introduction: Anastomotic leak is a devastating complication after colorectal surgery. There is paucity of data on non-gastrointestinal complications after anastomotic leak in this population. We aimed to investigate non-gastrointestinal complications, as well as causes of major morbidity and mortality following anastomotic leak after colorectal resection and hypothesized that non-gastrointestinal complications after anastomotic leak are a sizable proportion of the overall morbidity and mortality in this population. Methods: We used the ACS NSQIP database, and searched for CPT codes for colorectal procedures with primary anastomosis between 2015-2019. The cohorts (anastomotic leak vs. no-leak) were aligned using propensity score matching, and 30-day mortality, length of stay, and readmission outcomes were compared. Results: We identified 4881 patients with anastomotic leak and 150331 patients with no-leak. The overall leak rate was 3.14%. Anastomotic leak group had an 85% longer length-of-stay. Predicted mean (95% CI) length-of-stay for the leak group was 10.2 (9.9-10.5) days vs. 5.5 (5.4-5.7) days for the no-leak group. Anastomotic leak was associated with a higher 30-day risk of unplanned return to the operating room (OR 34.5; 95% CI 27.2-43.8), and thirty-day mortality (OR 2.8; 95% 2.2-3.5). Anastomotic leak was associated with a higher incidence of pulmonary complications including: pneumonia (OR 4.4; 95% CI 3.5-5.6), unplanned intubation (OR 6.3; 95% CI 4.8-8.3), mechanical ventilation (OR 6.3; 95% CI 5.1-8.0), and pulmonary embolism (OR 4.3; 95% CI 2.6-7.0); cardiac complications, including myocardial infarction (OR 2.9 (95% CI 2.0-4.2) and cardiac arrest (OR 3.2; 95% CI 2.1-4.9); and new-onset renal failure requiring dialysis (OR 3.8; 95% CI 2.6-5.5). There was no significant difference in risk of acute kidney injury (OR 1.1; 95% CI 0.6-2.0), and stroke (OR 1.8; 95% CI 0.9-3.6). Conclusion: Colorectal anastomotic leak independently lengthens length-of-stay, and is associated with increased mortality (2.7% vs. 7.2%) after colorectal surgery with an enteric anastomosis.