Estimating the risk of complications related to re-exploration for bleeding after adult cardiac surgery: a systematic review and meta-analysis

OBJECTIVE: The aim of this study was to evaluate the impact of re-exploration for bleeding after cardiac surgery on the immediate postoperative outcome. METHODS: Systematic review of the literature and meta-analysis of data on re-exploration for bleeding after adult cardiac surgery were performed. RESULTS: The literature search yielded eight observational studies reporting on 557 923 patients and were included in the present analysis. Patients requiring re-exploration were significantly older, more frequently males, had a higher prevalence of peripheral vascular disease and preoperative exposure to aspirin, and more frequently underwent urgent/emergency surgery. Re-exploration was associated with significantly increased risk ratio (RR) of immediate postoperative mortality (RR 3.27, 95% confidence interval (CI) 2.44-4.37), stroke, need of intra-aortic balloon pump, acute renal failure, sternal wound infection, and prolonged mechanical ventilation. The pooled analysis of four studies (two being propensity score-matched pairs analysis) reporting adjusted risk for mortality led to an RR of 2.56 (95% CI 1.46-4.50). Studies published during the last decade tended to report a higher risk of re-exploration-related mortality (RR 4.30, 95% CI 3.09-5.97) than those published in the 1990s (RR 2.75, 95% CI 2.06-3.66). CONCLUSIONS: This study suggests that re-exploration for bleeding after cardiac surgery carries a significantly increased risk of postoperative mortality and morbidity.