Investigation of Risk Factors Related to the Development of Hepatic Dysfunction in Patients with a Low and Moderate Cardiac Risk During Open-Heart Surgeries

Abstract Objective: To determine the possible risk factors associated with hepatic dysfunction during open-heart surgeries. Methods: After excluding 71 patients, 307 patients with possible low and moderate cardiac risk who underwent either coronary artery bypass graft surgery (CABG) (n=176) or valve repair surgery (mitral valve, mitral and aortic valves and/or tricuspid valve) (n=131) were investigated prospectively during a 6-month period. Hyperbilirubinemia is defined as an occurrence of a plasma total bilirubin concentration >34 µmol/L (2 mg/dL) in any measurement during the postoperative period; the patients were divided into groups with or without postoperative hyperbilirubinemia. The collected parameters were: alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total bilirubin (TBil), gamma-glutamyl transpeptidase (GGT) and albumin. The parameters were collected preoperatively and postoperatively on days 1, 3 and 7. Preoperative, intraoperative, and postoperative risk factors were investigated. Logistic regression analysis was performed to identify the risk factors for postoperative hyperbilirubinemia. Results: Postoperative hyperbilirubinemia was observed in 7 of 176 patients (4%) who underwent CABG, and in 11 of 131 patients (8.4%) who underwent valve replacement surgeries. Independent risk factors for early postoperative hyperbilirubinemia were found as: ejection fraction (EF), aortic cross-clamp (ACC) time, intensive care unit stay and extubation time (P<0.001). In comparison to CABG procedures, postoperative hyperbilirubinemia was observed more frequently in patients undergoing valve surgeries (P=0.027). Conclusion: Low EF and prolonged ACC time are significant independent risk factors for early postoperative hyperbilirubinemia during open-heart surgeries with cardiopulmonary bypass. Valve surgeries show a higher incidence of hyperbilirubinemia in comparison to CABG.

摘要
研究目的：明确心脏直视手术期间肝功能异常相关的潜在危险因素。
研究方法：本研究前瞻性纳入6个月内入组的307例心脏风险为低至中度的患者，术前已排除71例不符合标准的患者。所有患者均接受冠状动脉旁路移植术（coronary artery bypass graft surgery, CABG，n=176）或瓣膜修复术（包括二尖瓣、二尖瓣联合主动脉瓣及/或三尖瓣修复术，n=131）。本研究将高胆红素血症定义为：术后任意一次检测中血浆总胆红素浓度＞34 µmol/L（2 mg/dL），据此将患者分为术后高胆红素血症组与非高胆红素血症组。收集的检测指标包括丙氨酸氨基转移酶（alanine transaminase, ALT）、天冬氨酸氨基转移酶（aspartate transaminase, AST）、碱性磷酸酶（alkaline phosphatase, ALP）、总胆红素（total bilirubin, TBil）、γ-谷氨酰转移酶（gamma-glutamyl transpeptidase, GGT）以及白蛋白。分别于术前、术后第1、3、7天采集上述指标。对术前、术中及术后的危险因素进行调研，并采用logistic回归分析以明确术后高胆红素血症的危险因素。
研究结果：冠状动脉旁路移植术组176例患者中7例（4%）出现术后高胆红素血症，瓣膜手术组131例患者中11例（8.4%）出现术后高胆红素血症。术后早期高胆红素血症的独立危险因素为射血分数（ejection fraction, EF）、主动脉阻断（aortic cross-clamp, ACC）时长、重症监护病房停留时长以及拔管时间（P<0.001）。与冠状动脉旁路移植术相比，瓣膜手术患者术后高胆红素血症的发生率更高（P=0.027）。
结论：在采用体外循环（cardiopulmonary bypass）的心脏直视手术中，低射血分数与延长的主动脉阻断时长是术后早期高胆红素血症的重要独立危险因素。相较于冠状动脉旁路移植术，瓣膜手术患者的高胆红素血症发生率更高。