Association between Complications and Death within 30 days after General Surgery: A Vascular Events in Noncardiac Surgery Patients Cohort Evaluation (VISION) substudy

Abstract

Objective: To determine the epidemiology of post-operative complications among general surgery patients, inform their relationships with 30-day mortality, and determine the attributable fraction of death of each postoperative complication.

Background: The contemporary causes of post-operative mortality among general surgery patients are not well characterized.

Methods: VISION is a prospective cohort study of adult non-cardiac surgery patients across 28 centres in 14 countries, who were followed for 30 days after surgery. For the subset of general surgery patients, a cox proportional hazards model was used to determine associations between various surgical complications and post-operative mortality. The analyses were adjusted for preoperative and surgical variables. Results were reported in adjusted hazard ratios (HR) with 95% confidence intervals (CI).

Results: Among 7950 patients included in the study, 240 (3.0%) patients died within 30 days of surgery. Five post-operative complications (myocardial injury after non-cardiac surgery [MINS], major bleeding, sepsis, stroke, and acute kidney injury resulting in dialysis) were independently associated with death. Complications associated with the largest attributable fraction (AF) of post-operative mortality (i.e., percentage of deaths in the cohort that can be attributed to each complication, if causality were established) were major bleeding (n=1454, 18.3%, HR 2.49 95%CI 1.87-3.33, P<0.001, AF 21.2%), sepsis (n=783, 9.9%, HR 6.52, 95%CI 4.72-9.01, P<0.001, AF 15.6%), and MINS (n=980, 12.3%, HR 2.00, 95%CI 1.50-2.67, P<0.001, AF 14.4%).

Conclusion: The complications most associated with 30-day mortality following general surgery are major bleeding, sepsis, and MINS. These findings may guide the development of mitigating strategies, including prophylaxis for perioperative bleeding.