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

doi:10.3760/cma.j.issn.1673-4777.2014.07.007

Abstract：Objective To assess the performance of EuroSCORE Ⅱ in 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.Methods From 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.Results The 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).Conclusions EuroSCORE 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.