Cerebral monitoring with transcranial Doppler ultrasonography improves neurologic outcome during repairs of acute type A aortic dissection

Objective: Neurologic complications after repair of acute type A aortic dissection remain significant. The use of power M-mode transcranial Doppler monitoring to verify cerebral blood flow during these repairs might decrease cerebral ischemia by correcting malperfusion. The purpose of this study was to analyze the use of power M-mode transcranial Doppler monitoring during repairs of acute type A dissection with regard to neurologic outcome. Methods: We performed a prospective study of patients undergoing repairs of acute type A aortic dissection. Repairs included profound hypothermic circulatory arrest and retrograde cerebral perfusion. Patients in whom transcranial Doppler monitoring was used to monitor cerebral blood flow and modify operative technique during repair (study group) were compared with those without monitoring and modification (control group). Results: Between September 2001 and October 2003, we repaired 56 cases of acute type A dissection. Power M-mode transcranial Doppler monitoring was used in 50% (28/56) of cases. Power M-mode transcranial Doppler monitoring altered operative cannulation and guided retrograde cerebral perfusion flow in 28.5% (8/28) and 78.6% (22/28) of cases, respectively. Two patients presented with preoperative stroke, one in each group. One operative death occurred in each group. In-hospital mortality and the occurrence of new stroke were not significantly different between the 2 groups. Temporary neurologic dysfunction occurred less often in the study group (14.8% [4/27] vs 51.8% [14/27], P = .008). Conclusions: Identification of cerebral malperfusion requires cerebral monitoring. By ensuring cerebral blood flow by using power M-mode transcranial Doppler monitoring and correcting cerebral malperfusion by modifying operative technique, neurologic outcome was improved during repairs of acute type A aortic dissection.