title: Monitoring of somatosensory evoked potentials during temporary arterial occlusion in cerebral aneurysm surgery.
abstract: Somatosensory evoked potentials (SSEP) have been used during cerebral aneurysm surgery to monitor the integrity of neural pathways. The purpose of this study was to evaluate the effectiveness of SSEP monitoring as a predictor of neurological outcome during temporary arterial occlusion. In a series of 157 patients monitored, 97 patients had temporary occlusion of the feeding artery. Twenty-three patients developed a SSEP change during temporary occlusion, 15 reversible (recovery of the change after the release of occlusion), and 8 persistent (no recovery) changes. A persistent change predicted a postoperative neurological deficit in each case, whereas, of the 15 patients with reversible changes, only 5 had postoperative deficits. Seventy-four patients had no change on SSEP monitoring but 10 patients did have new neurological deficits postoperatively. The false positive rate was 43% and the false negative rate was 14%. SSEP was a better predictor of neurological deficits in patients with aneurysms of the carotid circulation than of the vertebral-basilar arteries. Despite these limitations, we find SSEP monitoring useful during temporary occlusion in cerebral aneurysm surgery.
authors.affiliation: Department of Anesthesia, University Hospital, London, Ontario, Canada.
authors.forename: P H
authors.initials: PH
authors.lastname: Manninen
authors.forename: A M
authors.initials: AM
authors.lastname: Lam
authors.forename: W E
authors.initials: WE
authors.lastname: Nantau