Gastrointestinal Complications after Coronary Artery Bypass Grafting: A National Study of Morbidity and Mortality Predictors

BACKGROUND: Previous single-institution studies have documented a 0.6% to 2.4% incidence of gastrointestinal (GI) complications after coronary artery bypass grafting (CABG), with an associated 14% to 63% mortality rate. To better determine the incidence and impact of GI complications after CABG, national outcomes for CABG were examined from 1998 to 2002. STUDY DESIGN: The Nationwide Inpatient Sample was queried for all patients undergoing CABG (ICD9 procedure codes 36.10 to 36.16). Two cohorts were compared: CABGs with and without GI complications. Both demographic and outcomes variables were compared by either t-test or chi-square analysis. Logistic regression analyses indicated potential predictors of CABG inpatient mortality and GI complications after CABG. RESULTS: The incidence of GI complications among 2.7 million CABGs identified was 4.1%. Total hospital length of stay (19.3 versus 8.8 days) and inpatient mortality (12.0% versus 2.5%, both p < 0.0001) were increased in CABG patients having GI complications. Factors associated with increased risk of GI complications included: age greater than 65 years (odds ratio [OR], 2.1); hemodialysis (OR, 3.4); intraaortic balloon pump (OR, 1.6); concomitant valve procedure (OR, 1.5); and procedure urgency (OR, 1.22). Use of an internal mammary graft was protective (OR, 0.5), but GI complications increased inpatient mortality risk (OR, 2.6). CONCLUSIONS: This national population-based study indicates that GI complications after CABG occur at a higher rate than previously described, leading to increased hospital length of stay and mortality.