Adverse Events and Risk Factors of Blood Transfusion in Cardiovascular Surgery: A Prospective Cohort Study

Abstract Background: Hemodilution, transoperative bleeding and cardiopulmonary bypass (CPB) are some of the factors associated with high transfusion rates in cardiac surgery. Objective: To analyze the incidence of blood transfusion and early postoperative outcomes in cardiac surgery patients. Methods: Cohort study of patients undergoing cardiac surgery in a university hospital, consecutively enrolled from May 2015 to February 2017. Data were prospectively collected and comparisons were made between two patients’ groups: transfused and not transfused. Student's t-test, chi-square test, and logistic regression were used, and a p-value < 0.05 was considered significant. Results: Among the 271 patients evaluated, 100 (37%) required transfusion in the transoperative (32.1%) and/or postoperative periods (19.5%). The following predictors of transfusion were identified by multivariate analysis: EuroScore II (OR 1.2); chronic kidney disease (CKD) (OR 3.2); transoperative bleeding ≥ 500 mL (OR 6.7); baseline hemoglobin (Hb) ≤ 10 g/dL (OR 11.5); activated partial thromboplastin time (aPTT) (OR 1.1) and CPB duration (OR 1.03). Transfusion was associated with prolonged mechanical ventilation (≥ 24h) (2.4% vs. 23%), delirium (5.9% vs. 18%), bronchopneumonia (1.2% vs. 16%), acute renal failure (3.5% vs. 25%), acute on CKD (0.6% vs. 8%), stroke or transient ischemic attack (1.8% vs. 8%), intensive care unit stay ≥ 72 h (36% vs. 57%), longer hospital stay (8 ± 4 days vs. 16 ± 15 days), as well as increased early mortality (1.75% vs. 15%). Conclusion: EuroScore II, CKD, major transoperative bleeding, preoperative Hb and aPTT values and CPB time were independent predictors of transfusion, which was associated with a higher rate of adverse outcomes, including early mortality.

摘要 背景：血液稀释、术中失血与体外循环（cardiopulmonary bypass，CPB）是导致心脏手术患者输血率偏高的部分相关因素。目的：分析心脏手术患者的输血发生率及术后早期转归情况。方法：本研究为队列研究，对象为2015年5月至2017年2月在某大学医院接受心脏手术的连续入组患者。研究数据前瞻性收集，并将患者分为输血组与非输血组两组进行比较。采用Student t检验、卡方检验及logistic回归分析，以P值<0.05作为差异具有统计学意义的判定标准。结果：纳入评估的271例患者中，100例（37%）在术中（32.1%）、术后（19.5%）或两阶段均需接受输血治疗。多因素分析识别出以下输血预测因素：EuroScore II（OR=1.2）、慢性肾脏病（chronic kidney disease，CKD）（OR=3.2）、术中失血量≥500 mL（OR=6.7）、基线血红蛋白（hemoglobin，Hb）≤10 g/dL（OR=11.5）、活化部分凝血活酶时间（activated partial thromboplastin time，aPTT）（OR=1.1）以及体外循环时长（OR=1.03）。输血与以下不良结局显著相关：机械通气时间延长（≥24 h，2.4% vs. 23%）、谵妄（5.9% vs. 18%）、支气管肺炎（1.2% vs. 16%）、急性肾衰竭（3.5% vs. 25%）、慢性肾脏病基础上的急性肾损伤（0.6% vs. 8%）、卒中或短暂性脑缺血发作（1.8% vs. 8%）、重症监护病房停留时长≥72 h（36% vs. 57%）、住院时间更长（8±4天 vs. 16±15天），以及早期死亡率升高（1.75% vs. 15%）。结论：EuroScore II评分、慢性肾脏病、大量术中失血、术前血红蛋白水平、活化部分凝血活酶时间以及体外循环时长均为心脏手术患者输血的独立预测因素，且输血与更高的不良事件发生率（包括早期死亡）相关。