Local anesthesia as a distinct comparator versus conscious sedation and general anesthesia in endovascular stroke treatment: a systematic review and meta-analysis

Background The optimal anesthetic modality for endovascular treatment (EVT) in acute ischemic stroke (AIS) is undetermined. Comparisons of general anesthesia (GA) with composite non-GA cohorts of conscious sedation (CS) and local anesthesia (LA) without sedation have provided conflicting results. There has been emerging interest in assessing whether LA alone may be associated with improved outcomes. We conducted a systematic review and meta-analysis to evaluate clinical and procedural outcomes comparing LA with CS and GA. Methods We reviewed the literature for studies reporting outcome variables in LA versus CS and LA versus GA comparisons. The primary outcome was 90 day good functional outcome (modified Rankin Scale (mRS) score of <= 2). Secondary outcomes included mortality, symptomatic intracerebral hemorrhage, excellent functional outcome (mRS score <= 1), successful reperfusion (Thrombolysis in Cerebral Infarction (TICI) >2b), procedural time metrics, and procedural complications. Random effects meta-analysis was performed on unadjusted and adjusted data. Results Eight non-randomized studies of 7797 patients (2797 LA, 2218 CS, and 2782 GA) were identified. In the LA versus GA comparison, no statistically significant differences were found in unadjusted analyses for 90 day good functional outcome or mortality (OR=1.22, 95% CI 0.84 to 1.76, p=0.3 and OR=0.83, 95% CI 0.64 to 1.07, p=0.15, respectively) or in the LA versus CS comparison (OR=1.14, 95% CI 0.76 to 1.71, p=0.53 and OR=0.88, 95% CI 0.62 to 1.24, p=0.47, respectively). There was a tendency towards achieving excellent functional outcome (mRS <= 1) in the LA group versus the GA group (OR=1.44, 95% CI 1.00 to 2.08, p=0.05, I-2=70%). Analysis of adjusted data demonstrated a tendency towards higher odds of death at 90 days in the GA versus the LA group (OR=1.24, 95% CI 1.00 to 1.54, p=0.05, I-2=0%). Conclusion LA without sedation was not significantly superior to CS or GA in improving outcomes when performing EVT for AIS. However, the quality of the included studies impaired interpretation, and inclusion of an LA arm in future well designed multicenter, randomized controlled trials is warranted.