急性StanfordA型主动脉夹层孙氏手术后机械通气时间延长的危险因素分析

Risk factors of prolonged mechanical ventilation after Sun＇s procedure for acute Stanford type A aortic dissection

目的评估欧洲评分Ⅱ是否能够有效预测急性Stanford A型主动夹层孙氏术后机械通气时间，探索孙氏术后机械通气时间延长的危险因素。方法自2009年12月至2012年2月共240例急性Stanford A型主动脉夹层的患者纳入研究。术后呼吸机机械通气时间超过48 h定义为机械通气时间延长。计算所有患者的欧洲评分。欧洲评分的区分能力采用受试者工作特征（ROC）曲线评估，校正能力采用HosmerLemeshow拟合优度检验评估。结果急性Stanford A型主动脉夹层孙氏术后院内总体病死率为10.0%（24/240），术后平均呼吸机机械通气时间为17.0（12.5,56.0）h。共74例患者术后机械通气时间延长。欧洲评分Ⅱ的区分能力（ROC曲线下面积=0.52）及校正能力（HosmerLemeshow,P〈0.05）均不佳。单因素分析结果显示年龄［比值比（OR）=2.88, P=0.00］、脑卒中病史（OR=1.04,P=0.03）、外周血白细胞计数（OR=3.19, P=0.00）、发病至手术时间小于1周（OR=3.68,P=0.001）、体外循环时间（OR=1.96,P=0.02）为术后院内死亡的危险因素。Logistic多因素分析年龄大于48.5岁（OR=3.85,P=0.00）、术前外周静脉血白细胞计数超过13.5×109/L（OR=4.05, P=0.00）、发病至手术时间小于1周（OR=3.75, P=0.002）是孙氏术后机械通气时间延长的危险因素。结论年龄、术前白细胞计数超过13.5×109/L、发病至手术时间小于1周是孙氏手术后机械通气时间延长的危险因素。欧洲评分Ⅱ不能有效预测急性Stanford A型夹层孙氏手术后机械通气时间延长。术前及术中采取措施减少外周血白细胞计数、减轻炎性反应可能是一种潜在的主动脉手术脏器保护策略。

ObjectiveTo assess the performance of EuroSCORE Ⅱin the prediction of prolonged mechanical ventilation after total aortic arch replacement treating acute Stanford Type A aortic dissection, and to evaluate the risk factors for prolonged mechanical ventilation. MethodsFrom December 2009 to February 2012, 240 patients who underwent total aortic arch replacement for acute Stanford type A aortic dissection were analyzed retrospectively. More than 48 hours of mechanical ventilation after the surgery was defined as postoperative prolonged mechanical ventilation. EuroSCORE Ⅱ was used to predict prolonged mechanical ventilation. A receiver operating characteristic （ROC） curve was used to test the discrimination of the model. Calibration was assessed with a HosmerLemeshow goodnessoffit statistics. Multiple logistic regression analysis was used to identify the final risk factors of prolonged mechanical ventilation. ResultsThe overall mortality was 10.0%（24/240）. The mean length of mechanical ventilation after total aortic arch replacement was 17.0（12.5, 56.0）hours. 74 of 240 patients needed prolonged mechanical ventilation. EuroSCORE Ⅱ showed that poor discriminatory ability （ROC curve was 0.52） and calibration （HosmerLemeshow,P〈0.05） could predict prolonged mechanical ventilation. With multivariate analysis, independent risk factors for postoperative prolonged mechanical ventilation were age ≥ 48.5 years [odds ratio（OR）=3.85,P〈0.01], preoperative leukocyte count of ≥ 13.5×109/L （OR=4.05,P〈0.01） and symptom onset before the surgery less than one week （OR=3.75, P=0.002）.ConclusionsEuroSCORE Ⅱ does not predict prolonged mechanical ventilation following total aortic arch replacement for acute Stanford type A aortic dissection. Preoperative high level of leukocyte, age and surgical period from symptom onset are risk factors for prolonged mechanical ventilation.