Gastrointestinal Complications after Cardiac Surgery: Incidence, Predictors, and Impact on Outcomes

Background: The purpose of this study was to investigate the incidence, predictors, and long-term impact of gastrointestinal (GI) complications following adult cardiac surgery. Methods: Index Society of Thoracic Surgeons (STS) adult cardiac operations performed between January 2010 and February 2018 at a single institution were included. Patients were stratified by the occurrence of postoperative GI complications. Outcomes included early and late survival as well as other associated major postoperative complications. A sub-analysis of propensity score matched patients was also performed. Results: 10,285 patients were included, and the overall rate of GI complications was 2.4% (n=246). Predictors of GI complications included dialysis dependency, intra-aortic balloon pump, congestive heart failure, chronic obstructive pulmonary disease, and longer aortic cross-clamp times. Thirty-day (2.6% vs 24.8%), one- (6.3% vs 41.9%), and three-year (11.1% vs 48.4%) mortality were substantially higher in patients who experienced GI complications (all P<0.001). GI complication was associated with a three-fold increased hazard for mortality (HR 3.1, 95% CI 2.6-3.7) after risk adjustment, and there was an association between the occurrence of GI complications and increased rates of renal failure (39.4% vs 2.5%), new dialysis dependency (31.3% vs 1.5%), multisystem organ failure (21.5% vs 1.0%), and deep sternal wound infections (2.6% vs 0.2%)(all P<0.001). These results persisted in propensity-matched analysis. Conclusions: GI complications are infrequent but have a profound impact on early and late survival, and often occur in association with other major complications. Risk factor modification, heightened awareness, and early detection and management of GI complications appears warranted.