Delayed re-exploration for bleeding after coronary artery bypass surgery results in adverse outcomes.

OBJECTIVE We aimed to identify the impact of re-exploration for bleeding after coronary artery bypass grafting (CABG) and the effect of time delay, re-exploration within 12h (<12h) versus 12h or later (>or=12h). METHODS Analyses of prospective clinical data on 3220 consecutive patients who underwent CABG between 2003 and 2005 were performed. Pearson chi(2) tests, Fisher's exact tests, Student's t-tests, Mann-Whitney U tests, or univariate logistic regression analysis were used to assess the effects of pre-operative and operative characteristics on re-exploration, and the effects of re-exploration and time delay on adverse outcomes. Predictors of re-exploration and its effect on adverse outcomes were further evaluated using multiple logistic regression analysis. RESULTS One hundred ninety-one patients (5.9%) underwent re-exploration for bleeding. Re-explored patients as a group in comparison to the non-re-explored group had increased postoperative blood loss, transfusion requirements, duration of mechanical ventilation, ICU stay, intra-aortic balloon pump (IABP) and haemofiltration support, and mortality (all p<0.001). One hundred fifty-seven (82%) of the 191 patients were re-explored <12h. The group of patients who were re-explored <12h in comparison to >or=12h group had shorter ICU stay (median 3 vs 8.5 days; p<0.001), less IABP support (22.3 vs 44.1%; p=0.009) and a lower mortality (7 vs 29.4%; p=0.001). There was no significant difference in blood loss or transfusion requirements between the two groups. The predicted EuroSCORE risks of the <12h group was 6.66% and the observed mortality was 7% (p=0.865). The observed mortality of 29.4% in the >or=12h group was significantly higher than the predicted EuroSCORE risks of 7.59% (p<0.001). CONCLUSIONS Patients requiring re-exploration for bleeding are at higher risk of adverse outcomes and this risk is increased if time to re-exploration is prolonged for 12h or longer.