Risk factors analysis of hyperbilirubinemia after off-pump coronary artery bypass grafting: a retrospective observational study.

Background: Hyperbilirubinemia is a common complication after off-pump coronary artery bypass grafting (OPCAB), but the incidence and the risk factors are unclear. This study aimed to analyze the incidence and risk factors of postoperative hyperbilirubinemia in patients undergoing OPCAB.

Methods: From December 2016 to March 2019, a total of 416 consecutive patients undergoing OPCAB were enrolled in this single-center retrospective study. Patients were divided into the normal serum total bilirubin group and the hyperbilirubinemia group based on the serum total bilirubin levels. Perioperative variables between the two groups were compared by univariate logistic regression analysis. Then, multivariate binary logistic regression analysis was used to analyze the independent risk factors of developing hyperbilirubinemia in patients underwent OPCAB. P < 0.05 was considered as statistically significant.

Results: Thirty two of 416 (7.7%) patients developed postoperative hyperbilirubinemia. Univariate regression analysis showed significant differences in gender (73.96% vs. 93.75%, P = 0.012), preoperative total bilirubin levels (11.92 ± 4.52 vs. 18.28 ± 7.57, P < 0.001), perioperative IABP implantation (22.66% vs. 43.75%, P = 0.008), perioperative blood transfusion (37.50% vs. 56.25%, P = 0.037) between the two groups. Multivariate logistic regression analysis revealed that elevated preoperative serum total bilirubin levels (OR = 1.225, 95% CI 1.145-1.310, P < 0.001), perioperative blood transfusion (OR = 4.488, 95% CI 1.876-10.737, P = 0.001) and perioperative IABP implantation (OR = 4.016, 95% CI 1.709-9.439, P = 0.001) were independent risk factors for hyperbilirubinemia after OPCAB.

Conclusions: Hyperbilirubinemia is also a common complication after OPCAB. Elevated preoperative serum total bilirubin levels, perioperative blood transfusion, and perioperative IABP implantation were independent risk factors for patients developing hyperbilirubinemia after OPCAB. Further studies need to be conducted to confirm the risk factors of hyperbilirubinemia after OPCAB procedure.