ObjectiveTo investigate the effect of conscious sedation (CS) on functional outcome and complication rates after intra-arterial treatment (IAT) for acute ischemic stroke (AIS) compared to the use of local anesthesia (LA) at the puncture site only.MethodsPatients undergoing IAT for AIS with CS or LA in the Erasmus University Medical Center from March 2014 to June 2016 were included for analysis. The primary outcome was the score on the ordinal modified Rankin Scale (mRS). We compared CS to LA by ordinal logistic regression with covariate adjustment using propensity scoring.ResultsIn 146 AIS patients treated with IAT, use of CS was associated with a shift towards worse mRS scores (odds ratio [OR] 0.4 [95% confidence interval (CI) 0.2–0.7]) compared to LA. Mortality after 90 days was higher in the CS group compared to the LA group (OR 2.3 [95% CI 1.0–5.2]). No differences between groups were noted with regard to procedure duration (8 minutes, β = 6.3 [95% CI −7.4 to 20.0]) or occurrence of procedure-related complications (OR 1.3 [95% CI 0.6–2.7]).ConclusionCS was associated with poor functional outcome and increased mortality rates compared to LA. Furthermore, CS did not reduce duration of intervention or interventional complications. CS during IAT for AIS is of no benefit if LA is considered safe.Classification of evidenceThis study provides Class II evidence, because of nonrandom allocation, that for patients with AIS undergoing IAT, LA rather than CS improves functional outcome.