Effect of Nitrous Oxide on Neurologic Function Following Intracranial Aneurysm Surgery

Abstract

Vasospasm that occurs after subarachnoid hemorrhage (SAH), despite successful surgical or radiological intervention remains with an ominous prognostic recovery period. 1 We investigated the correlation of S100B protein in CSF and serum with incident of vasospasm and neurological outcome in patients undergoing intracerebral aneurysm clipping. Twenty five patients were enrolled. All patients received combined anesthetic techniques. Brain protection was provided by isoflurane. A CSF sample (2 cc) and blood sample (5 cc) were drawn 3 times (before skin incision, 30 minutes and 24 hours after clipping). Patients were followed for the incidence of vasospasm in Neurosurgical Intensive Care Unit and the neurological status at discharged was assessed using Glasgow Outcome Scale. Compared with baseline level (at 0 minute) we found that early changes in CSF S100 B level at 30 minutes significantly correlate with vasospasm (P = 0.005, sensitivity 90% and specificity 90%) but the correlation dissipated at 24 hours. In addition, early changes in S100B in CSF at 30 minutes significantly correlate with neurological outcome (P = 0.003). The relationship persisted at 24 hours (P , 0.011). In Serum we found no significant correlation between S100B at 30 minutes or 24 hours with either vasospasm or neurological outcome. We conclude that changes of S100B level in CSF in patients undergoing intracerebral aneurysm clipping surgery are strongly correlated with vasospasm and can be a reliable diagnostic tool to identified patients who are endangered with evolving vasospasm after a successful securing aneurysm surgery. Reference: 1. Pluta RM. Delayed cerebral vasospasm and nitric oxide: review, new hypothesid, and proposed treatment.