ABSTRACT
The authors analysed a total of 152 surgical interventions on the brachiocephalic arteries (BCAs) performed in 142 patients. All the patients were subjected to intraoperative monitoring of cerebral haemodynamics by means of transcranial Doppler (TCD) ultrasonography simultaneously accompanied by electroencephalography (EEG). Additionally, the state of the reconstructed carotid arteries was controlled by means of ultrasonographic duplex scanning (USDS). Comparing the findings of the TCD recording and EEG made it possible to single out 5 groups of the operated patients. The EEG technique turned out to have more informative value as compared with TCD ultrasonography in determining the degree of cerebral ischaemia during clamping of the carotid arteries (CAs). Nine (5.9%) patients demonstrated lower tolerance of the brain to ischaemia, and the operation on the BCA was performed with the use of a temporal intraluminal bypass graft. Microembolic signals (MES) were registered in 54.6% of cases. Single MES were detected in six patients, sporadic MES--in 53, and multiple MES--in 24. Mention should be made that the--MES associated with the placement of the bypass graft appeared to be multiple and were registered in all the operated patients. Diffusion-weighted magnetic resonance tomography revealed fresh foci of lacunar cerebral infarctions in 14 (25%) of the 56 patients thus examined. Intraoperative USDS of the reconstructed carotid arteries revealed floatation of the residual remnants of the intima in two patients, which was the cause of a repeat intervention. Combined monitoring of cerebral haemodynamics makes it possible to timely prevent cerebral ischaemia, to narrow the indications for placement of an intraluminal bypass graft, and to dramatically decrease the rate of postoperative complications.