Role of anesthesia for endovascular treatment of ischemic stroke: do we need neurophysiological monitoring?

T he use of acute endovascular stroke intervention was called into question after the results of 2 negative stroke endovascular trials (Interventional Management of Stroke 3 [IMS-3] and Systemic Thrombolysis for Acute Ischemic Stroke per the Stroke Center registry [SYNTHESIS]). 3 compared patients with acute stroke with proximal anterior circulation artery occlu-sions with usual stroke care, including intravenous tissue-type plasminogen activator (tPA). The study demonstrated a favorable shift in outcomes in the interventional group by modified Rankin Scale (mRS) by 90 days (odds ratio [OR], 1.67; 95% confidence interval [CI], 1.21–2.30). Improvement in mRS was noted for all categories except for death. General anesthesia (GA) was used in 38% of the patients in the interven-tional group of MR CLEAN. In contrast, 9% of the patients in the Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE) 4 trial received GA. The rate of functional independence (mRS, 0–2 by 90 days) was higher in the intervention group (53.0% versus 29.3%; P<0.01). Furthermore, lower mortality rate was seen in intervention group (10.4 versus 19.0; P=0.04). A recent meta-analysis by Fargen 5,6 included MR CLEAN and the prior endovascular stroke trials and suggested a favorable shift outcome (mRS, 0–2; good outcome by 90 days; OR, 1.67; 95% CI, 1.29–1.16; P=0.0001) for patients with large-vessel occlu-sions who receive interventional therapy. In a post hoc analysis of MR CLEAN for use of GA, Berkhemer reported at the International Stroke Conference in Nashville, TN, a favorable effect when non-GA was used instead of GA (mRS, 0–2 at 90 days 38% versus 23%; P=0.013). 7 Also, GA was associated with delayed initiation of interventional therapy in comparison with conscious sedation (CS; 162±69 versus 134±60 minutes). Moreover, conversion from non-GA to GA was 6 of 137 (4.4%). Interestingly, there was no significant difference in time to revascularization as well as procedural duration. Thus, the authors proposed not using GA for faster interventional treatment initiation. The purpose of this article is to review the literature on the implications of anesthesia during acute stroke intervention based on recent trials and provide evidence about potential neurophysiological monitoring techniques to monitor such acute stroke intervention patients during GA. Do patients with acute stroke requiring endovascular intervention who receive GA far better than those who receive CS or monitored anesthesia care? The available literature 3,4,8–17 suggests that patients who receive GA actually do worse than those who receive CS or monitored …