Objective: To investigate the influences of deep hypothermic circulatory arrest (DHCA) on postoperative cranial nerve function in patients undergoing surgery for type A aortic dissection.

Methods: A total of 100 patients undergoing DHCA during the surgery for type A aortic dissection in our hospital were selected as the study subjects. After surgery, 32 patients with neurological complications were assigned to Group A, and 68 patients without neurological complications were assigned to Group B. The clinical outcomes were compared between the two groups, and the risk factors of postoperative neurological complications were analyzed by univariate and multivariate logistic regression analysis.

Results: During the surgery, patients underwent cerebral perfusion at 5 min and 10 min during DHCA had remarkably decreased cerebral oxygen saturation (rSO2) and VmMCA than those before anesthesia induction (P<0.05). After recovery of CPB, rSO2 and mean velocity in middle cerebral artery (VmMCA) recovered to the preoperative levels. The correlation analysis revealed a positive correlation between rSO2 and VmMCA (P<0.05). The univariate analysis suggested that the history of hypertension, hydropericardium, surgical duration, duration of cardiopulmonary bypass (CPB), aortic occlusion, ICU, and ventilator-assisted respiration, and hypoxemia significantly affected postoperative cranial nerve function (P<0.05). The logistic multivariate regression analysis demonstrated that the duration of CPB and aortic occlusion and hypoxemia were independent risk factors for postoperative cranial nerve dysfunction (P<0.05).

Conclusion: There were noticeable changes in hemodynamic and blood oxygen parameters in patients with type A aortic dissection undergoing DHCA during the perioperative period. The long duration of CPB and aortic occlusion and preoperative hypoxemia are the independent risk factors leading to postoperative impaired cranial nerve function.