Role of Intraventricular Sodium Nitroprusside in Vasospasm Secondary to Aneurysmal Subarachnoid Haemorrhage: A 5-year Prospective Study with Review of the Literature

Abstract

Cerebral vasospasm remains an important cause of permanent neurological injury and death following aneurysmal subarachnoid haemorrhage, despite the best current medical therapy. Sodium nitroprusside was recently suggested as a treatment option for cerebral ischaemia in patients with severe medically refractive vasospasm after subarachnoid haemorrhage. Twenty patients of aneurysmal SAH with severe vasospasm, corroborated on transcranial Doppler (TCD), were included in this prospective study. The neurological condition of all patients was classified as Hess and Hunt grade II or higher. The diagnosis of severe delayed cerebral vasospasm refractory to conventional treatment (HHH therapy and nimodipine) was established before treatment. Ten patients received intraventricular sodium nitroprusside (SNP), while the other 10 had either major systemic illness or did not consent, formed the control group of the study. SNP was instilled in escalating doses with a starting dose of 4 mg/mL and reversal of vasospasm was monitored on neurological examination along with TCD in a basic ICU setting without the need for neurophysiological or invasive monitoring. All patients in the study group showed an improvement in TCD velocities post-SNP instillation. Adverse effects were vomiting and hypotension in the SNP group which responded to medical management. The overall neurological outcome was good or excellent in 7/10 patients in the SNP group. Comparison between the two groups revealed improvement in TCD velocities and GCS in the SNP group thus affecting the long-term prognosis. Intraventricular sodium nitroprusside represents a promising method of treatment for established delayed cerebral vasospasm and cerebral ischaemia refractory to conventional treatment.