Cerebral monitoring during cardiovascular surgery.

PURPOSE OF REVIEW: Recent publications have reported on the neurologic complications in cardiovascular surgery. They are frequent, and have surpassed the mortality rate in cardiac surgery. Brain injury compromises surgical results and the patient's outcome. This review reports on the recent literature on neuromonitoring tools used to prevent and reduce brain injury in cardiovascular surgery.

RECENT FINDINGS: In the past year a good correlation between cerebral oxymetry and flow velocity by transcranial Doppler ultrasonography during carotid endarterectomy has been demonstrated, but this technique did not detect reliable flow velocity in 35% of cases. Transcranial Doppler ultrasonography, near-infrared spectroscopy and stump-pressure measurement have emerged with similar levels of accuracy for detecting cerebral ischemia, but, owing to the high number of technical difficulties, transcranial Doppler ultrasonography seems less practical than the other monitoring methods. In cardiac surgery multimodal monitoring seems to be more effective than single tools. There is evidence for a lack of established monitoring.

SUMMARY: Neuromonitoring tools may guide both intervention and treatment, and are aimed at reducing brain damage during cardiovascular surgery, especially when combined in multimodality monitoring. Further prospective, double-blind, randomized outcome studies are needed to determine the optimal neurologic monitoring modality (or modalities) in specific surgical settings.