RecruitingDevice studySafety, Feasibility, and Efficacy of Non-invasive Vagus Nerve Stimulation (nVNS) in the Treatment of Aneurysmal Subarachnoid HemorrhageThis is a single-site, single-arm, open-label pilot study assessing the safety, feasibility, and efficacy of non-invasive vagus nerve stimulation (nVNS), gammaCore, for the acute treatment of aneurysmal subarachnoid hemorrhage (SAH) subjects in a neurocritical care setting. 25 patients will be enrolled, all treated with an active device. The primary efficacy outcomes are reduced aneurysm rupture rate, reduced seizure and seizure-spectrum activity, minimized hemorrhage grades, and increased survival.