Brain Complications And Perioperative Brain Protection After Acute Type A Aortic Dissection

Background:Acute Stanford Type A Aortic Dissection(a TAAD)is a critical cardiovascular disease with high mortality.Although surgery is considered as the most effective method,the timing and methods of surgery for a TAAD patients with preoperative cerebral ischemia are still uncertain.Meanwhile,postoperative cerebral complication is one of the most common complications after surgical treatment.How to evaluate postoperative cerebral complications is important and essential.The alternative brain protective strategy for different kinds of surgical procedures is still need further analysis during the clinical practice.Purpose:Through this retrospective study,we intended to further clarify the timing and affecting factors of surgical treatment in a TAAD patients with cerebral ischemia;analyze the risk factors and outcomes of postoperative cerebral complications and analyze the application strategies of different cerebral protection measures.MethodsTotal of 1488 a TAAD patients were admitted to the Department of Cardiothoracic Surgery,Nanjing Medical University Drum Tower Clinic School of Medicine from 2002 to 2020,of which 1380 received surgical treatment.All patients were divided into cerebral ischemia group(CI,N=153)and non-cerebral ischemia group(Non-CI,N=1335)according to the diagnosis of preoperative cerebral ischemia;on the other hand,patients underwent surgical treatment were grouped according to the diagnosis of postoperative cerebral complications: cerebral complications group(CC,N=104)and no cerebral complications(Non-CC,N=1276).Through single variate comparison and multi-variates regression analysis,the protective factors for patients with cerebral ischemia and the operation-related risk factors that affect postoperative cerebral complications are studied.Next,a total of 672 patients with a TAAD admitted from January 2018 to December 2020 who underwent circulatory arrest surgery were analyzed separately.Among them,53 patients were excluded due to preoperative cerebral ischemia.Finally,619 a TAAD patients were divided into three groups according to the surgical procedures: Hemi-Arch subtotal arch surgery group(127 patients),total arch replacement group Total-Arch(244 patients)and arch stent group Arch-Stent(248 patients).30-day mortality,postoperative cerebral complications and intraoperative brain oxygen changes were used as the judging endpoints,and the effects of different brain protection strategies in different surgical groups were analyzed.ResultsThe mortality rate of the whole patients was 16.9%(252/1488),open surgery was a protective factor to reduce mortality(OR 0.100,95% CI 0.063-0.158;P<0.001).The 30-day mortality rate of the surgical patients was 13.7%(189/1380),and the incidence of cerebral complications was 7.5%(104/1380).Patients with postoperative cerebral complications were more likely to recover when the preoperative cerebral ischemia time was less than 12.75 hours.Instead,the coma patients were at a high risk of continuous brain complications and death after surgery.The total arch replacement was more likely to cause postoperative brain complications(OR 2.271,95%CI 1.470-3.510;P<0.001).The circulatory arrest hypothermia had little impact on postoperative cerebral complications.Axillary artery cannulation would reduce the incidence of postoperative cerebral complications(OR 0.473,95%CI 0.270-0.830;P=0.009),while femoral artery cannulation would increase it(OR 2.002,95%CI1.470-3.510;P=0.003).Cerebral perfusion has no significant effect on the occurrence of postoperative cerebral complications.In the Hemi-Arch group,the cerebral perfusion group was found lower incidence of mortality and stroke.The application of antegrade cerebral perfusion in the Total-Arch group could reduce postoperative mortality and cerebral oxygen changes.Under the different temperature,the longer of the deep hypothermia circulatory arrest time,the greater changes of the brain oxygen saturation.ConclusionsAlthough preoperative cerebral ischemia is an important risk factor for postoperative mortality and cerebral complications,open surgery is still the most effective treatment methods.Transient ischemia(syncope)as the main manifestation has good postoperative recovery,coma patients have poor postoperative recovery.The preoperative cerebral ischemia time less than 12.75 hours would still have a good outcome after open surgery;total arch replacement procedure and femoral artery cannulation would significantly increase the incidence of posterior cerebral complications,on the other hand,axillary artery cannulation may reduce the incidence of postoperative cerebral complications.Different cerebral perfusion methods and different hypothermic strategies have no significant impact on postoperative cerebral complications.Cerebral complications had a wide spectrum of the clinical manifestations and significantly increase the postoperative mortality rate.