The Effect Of Moderate Hypothermia Circulatory Arrest Anesthesia On Postoperative Pulmonary Function In Patients Undergoing Stanford Type A Aortic Dissection Operation

Objective:To investigate whether the moderate hypothermia(26-31 ℃)circulation arrest anesthesia has advantages in the postoperative recovery of pulmonary function to deep hypothermia(20-25 ℃)circulation arrest anesthesia in patients undergoing Stanford type A aortic dissection surgery.Methods:Retrospective analysis was performed on 135 patients with Stanford type A aortic dissection who underwent aortic arch replacement in The Second Hospital of Jilin University from January 2017 to December 2019.According to intraoperative circulation arrest rectal temperature,patients were divided into deep hypothermia group(control group,n=65)for 20-25℃ and moderate hypothermia group(observation group,n=70)for 26-31 ℃.We recorded and analyzed the preoperative general condition,surgical time,extracorporeal circulation time,cooling time,circulation arrest time,thawing time,postoperative extubation time,ICU care duration,secondary intubation case,pulmonary infection cases,total hospitalization days,postoperative nosocomial death case and postoperative blood gas analysis PaO2,PaCO2,FiO2 for 5days of two groups of patients.Indexes such as OI and postoperative acute lung injury(ALI)rate were calculated and counted.The conclusion is obtained by comparing and analyzing the data.Results:There were no significant differences in preoperative general conditions including gender,age,body mass index,cardiac function,complications(hypertension,diabetes,coronary heart disease,cerebral infarction,etc.).There were no significant differences in operative time,extracorporeal circulation time,ascending aorta occlusion time and circulation arrest time between the two groups.Thedifference of cooling time and rewarming time between the two groups was statistically significant(P<0.01).The observation group had shorter cooling and rewarming time than the control group.There were no significant differences in postoperative extubation time,ICU care duration,secondary intubation rate,pulmonary infection rate,total hospitalization stays and postoperative nosocomial death rate between the two groups.There were significant differences of postoperative ALI rate between the two groups(P<0.05).ALI rate in the observation group was lower than that in the control group.There were significant differences of oxygenation index(OI)within 3 days after surgery(P<0.05).OI in the observation group was higher than that in the control group.There was no statistically significant difference in OI between the two groups on day 4 and day 5 after surgery.There was no significant difference in postoperative PaCO2 between the two groups.Conclusion:Both moderate and deep hypothermia circulation arrest anesthesia can lead to postoperative pulmonary function changes in patients undergoing Stanford type A aortic dissection surgery.However,moderate hypothermia has advantage in the recovery of postoperative pulmonary function compared with the deep hypothermia.