Analysis Of Risk Factors For Postoperative In-hospital Death In Patients With Acute Standford A Aortic Dissection Under Hypothermia Circulatory Arrest

Objective:Acute Stanford type A aortic dissection is one of the critical diseases in cardiovascular surgery.The prognosis of patients with acute Stanford type A aortic dissection is poor and the hospital mortality is high.The purpose of this study is to review and analyze the clinical data of patients with acute Stanford A aortic dissection under hypothermia circulatory arrest in Affiliated Hospital of Qingdao University,to study the risk factors of postoperative death,and to explore the dynamic changes of lactate during operation,so as to improve the survival rate and prognosis of patients.Method:This is a single center retrospective clinical study.From June 2016 to December 2019,we selected patients undergoing acute Stanford type A aortic dissection under hypothermia circulatory arrest in Affiliated Hospital of Qingdao University as the study object.According to the postoperative outcome,the patients were divided into survival group and death group,The general data before operation,the data of hypothermia circulatory arrest and lactate growth rate,lactate level T₁（basic value）,T₂（beginning of cardiopulmonary bypass）,T₃（end of cardiopulmonary bypass）,T₄（before leaving the operating room）,lactate growth rate and average lactate level during operation,the worst parameters and clinical outcome after operation were recorded.Statistical software for the corresponding data analysis.Results:The hospital mortality rate was 19.7%.In univariate analysis,body mass index,preoperative ejection fraction,preoperative ALT,preoperative AST,preoperative urea nitrogen,cardiopulmonary bypass time,aortic occlusion time,circulatory arrest time,intraoperative minimum mean arterial pressure,lactate level at T₁-T₄,intraoperative lactate growth rate,intraoperative lactate concentration,intraoperative blood loss,blood transfusion related indexes（autotransfusion volume,red blood cell volume and plasma volume）,operation time,intraoperative urine volume and ultrafiltration volume were statistical different between the two groups.The above variables were included in the multivariate regression analysis.In multiple logistic regression analysis,body mass index（OR=1.035;95%CI 1.001-1.070;p=0.046）,intraoperative blood loss（OR=1.371;95%CI 1.088-1.726;p=0.007）and lactate level（OR=1.479;95%CI 1.128-1.940;p=0.005）,lactate growth rate（OR=3.637;95%CI 1.786-7.406;p<0.001）were the risk factors for hospital death.Spearman’s rank correlation coefficient analysis showed that:AST（r=0.358,p<0.001）,aortic occlusion time（r=0.160,p=0.025）,circulatory arrest time（r=0.160,p=0.024）,cardiopulmonary bypass time（r=0.264,p<0.001）,operation time（r=0.226,p=0.002）,ultrafiltration volume（r=0.167,p=0.020）,intraoperative blood loss（r=0.228,p=0.001）,autotransfusion volume（r=0.249,p<0.001）were positively correlated with the lactate level at T₃.There was a positive correlation between AST（r=0.180,p=0.120）,circulatory arrest time（r=0.175,p=0.015）,cardiopulmonary bypass time（r=0.151,p=0.036）,autotransfusion volume（r=0.197,p=0.006）and lactate growth rate.There was a positive correlation between AST（r=0.537,p<0.001）,serum creatinine（r=0.268,p<0.001）,mechanical ventilation time（r=0.177,p=0.013）and lactate level at T3.There was a positive correlation between AST（r=0.418,p<0.001）,SCR（r=0.231,p=0.001）,mechanical ventilation time（r=0.112,p=0.120）and lactate growth rate.Conclusion:The mortality of patients with aortic dissection was higher.Body mass index,blood loss,lactate level at T₃ and lactate growth rate were risk factors for postoperative hospital mortality in patients with hypothermic circulatory arrest aortic dissection.The growth rate of lactate and the level of lactate at T₁-T₄ in the dead group were higher than those in the survival group.The increase of lactate during operation is mainly concentrated during cardiopulmonary bypass.The changes of lactate during operation were closely related to the postoperative outcome.