Postoperative Complications and Readmission
In an unmatched comparison, patients who experienced postoperative GI complications also experienced higher rates of reoperation (50.9% vs 14.3%), concurrent multi-system organ failure (27.7% vs 1.3%), renal failure (44.6% vs 8.9%), and new dialysis dependency (41.1% vs 5.4%) (all, P<0.001). Rates of stroke, cardiac tamponade, and deep sternal wound infections were similar. Median hospital length of stay was longer in patients with GI complications (20 days [IQR 10 to 32] vs 10 days [IQR 7 to 17], P<0.001) (Table 2 ).
Median follow-up was 4.14 years (IQR 2.39 to 6.18). Long-term freedom from all-cause readmission was similar between cohorts (54.88% vs 52.36%, P=0.43). There were no differences in the rates of cardiac specific and heart failure readmission. Competing risk modeling was performed to identify risk-adjusted predictors for all-cause readmission. In this model, postoperative GI complications were associated with decreased hazards for all-cause readmission (HR 0.73, 95% CI 0.59 to 0.91, P=0.005), which may reflect the higher mortality rates in this group. Other significant predictors for all-cause readmission including increasing age (HR 1.01, 95% CI 1.00 to 1.01, P=0.002), female gender (HR 1.16, 95% CI 1.09 to 1.23, P<0.001), black race (HR 1.32, 95% CI 1.16 to 1.51, P<0.001), diabetes mellitus (HR 1.13, 95% CI 1.07 to 1.21, P<0.001), chronic obstructive pulmonary disease (HR 1.28, 95% CI 1.20 to 1.37, P<0.001), peripheral vascular disease (HR 1.27, 95% CI 1.18 to 1.36, P<0.001), immunosuppression (HR 1.34, 95% CI 1.19 to 1.51, P<0.001) and previous history of heart failure (HR 1.14, 95% CI 1.06 to 1.24, P=0.001). Other risk factors identified included history of hypertension, cerebrovascular disease, and increasing serum creatinine level. Factors associated with decreased risk of readmission included increasing serum albumin level, and cardiac presentation of NSTEMI or STEMI. These factors are shown inSupplemental Table 1 .