Effect of General Anesthesia versus Conscious Sedation/Local Anesthesia on the Outcome of Patients with Minor Stroke and Isolated M2 Occlusion Undergoing Immediate Thrombectomy: A Retrospective Multicenter Matched Analysis

Background: This study investigates the impact of general anesthesia (GA) versus conscious sedation/local anesthesia (CS/LA) on the outcome of patients with minor stroke and isolated M2 occlusion undergoing immediate mechanical thrombectomy (iMT). Methods: The databases of 16 comprehensive stroke centers were retrospectively screened for consecutive patients with isolated M2 occlusion and a baseline National Institute of Health Stroke Scale score ≤ 5 who received iMT. Propensity score matching (PSM) was used to estimate the effect of GA versus CS/LA on clinical outcome and procedure-related adverse events. Primary outcome measure was a 90-day modified Rankin Scale (mRS) score 0-1. Secondary outcome measures were 90-day mRS score 0-2 and all-cause mortality, successful reperfusion, procedural-related symptomatic subarachnoid hemorrhage (sSAH), intraprocedural dissections and new territory embolism. Results: Of the 172 patients that were selected, 55 received GA and 117 CS/LA. After PSM, 47 pairs of patients were available for analysis. We found no significant differences in clinical outcome, rates of efficient reperfusion and procedural-related complications between patients receiving GA or LA/CS. (mRS 0-1: p=0.815; mRS 0-2: p=0.401; all-cause mortality: p=0.408; modified Treatment In Cerebral Infarction score 2b-3: p=0.374; sSAH: p=0.082; intraprocedural dissection: p=0.408; new territory embolism: p=0.462) CONCLUSIONS: In patients with minor stroke and isolated M2 occlusion undergoing iMT, the type of anesthesia does not affect clinical outcome or the rate of procedural-related complications. Our results agree with recent data showing no benefit of one specific anesthesiologic procedure over the other and confirm their generalizability also to patients with minor baseline symptoms.