Impact of Stellate Ganglion Block in the Management of Cerebral Vasospasm: A Prospective Interventional Study.

Background: Stellate ganglion block (SGB) causes blockage of sympathetic nerve activity, which may lead to intracerebral vessel dilatation and relieve cerebral vasospasm in patients of aneurysmal subarachnoid hemorrhage (aSAH). Objective: The aim of this study was to evaluate the efficacy and safety of SGB to relieve cerebral vasospasm on clinicoradiological parameters. Materials and Methods: We prospectively included 20 patients with clinical and angiographic evidence of vasospasm post aneurysmal clipping. Cerebral blood flow velocity and Lindegaard ratio were assessed using transcranial Doppler (TCD). Location of vasospasm, vessel diameter, vasospasm severity, parenchymal filling time, and venous sinus filling time were assessed on digital subtraction angiography (DSA). Patients received ultrasound-guided SGB with 10 mL of 0.5% bupivacaine on the ipsilateral side of the vasospasm. After 30 minutes, the neurological status, TCD, and DSA parameters were reevaluated. Results: After SGB, there was statistically significant reduction in the middle cerebral artery (MCA) peak systolic velocity (P = 0.005), mean flow velocity (P = 0.025), and Lindegaard ratio (P = 0.022) on TCD. We observed significant dilatation in the mean vessel diameter measured at the mid-M1 segment of MCA (P = 0.003) and mid-A1 segment of ACA (P = 0.002) on DSA. The mean parenchymal filling time and mean venous sinus filling time decreased nonsignificantly after SGB (P = 0.163/0.104). Neurological improvement was observed in five (25%) patients. Conclusion: SGB has positive clinicoradiological influence in the management of cerebral vasospasm of large vessels. However, its effect on cerebral microvasculature is limited and needs a larger database for further analysis.