CANVAS 2020.

Study characteristics
Methods	Setting: single‐centre, China Design: RCT, 2 arms, open‐label, blinded endpoint (PROBE) Start date: 5 February 2016 (reported in protocol) Completion date: December 2022 (reported in protocol)
Participants	43 men and women randomised: experimental GA = 21, comparator CSA = 22; procedure interrupted in GA = 8 and CSA = 7; 1 GA and 2 CSA withdrawn due to large infarct and 0 lost to follow‐up was reported, 40 analysed Median age: 65 years (IQR 45–74 years) Gender (men/women): 26/14 Median NIHSS score 13.9 (score range: 10.2–16.0) 4 (18.2%) participants were converted from CSA to GA after randomisation because of significant agitation IV r‐tPA before EVT was not reported Diagnostic criteria: AIS with LVO in anterior cerebral circulation Inclusion criteria Aged ≥ 18 years Confirmed occlusion in anterior cerebral circulation by CTA or DSA Treatment initiated ≤ 6 hours after onset of symptoms who were previously functionally independent mRS 0–2 Exclusion criteria GSC < 8 Requiring tracheal intubation for airway protection and lung ventilation occlusion of posterior cerebral circulation (reported only in protocol) intracerebral haemorrhage Severely intubation and seizures NIHSS score < 8 or > 35 Known allergy to specific anaesthetics (propofol), or analgesics (sufentanil and remifentanil)
Interventions	Experimental: GA Anaesthesia induced with sufentanil 0.2 µg/kg and target‐controlled infusion with propofol 1–4 µg/mL. Muscle relaxation achieved with rocuronium 0.6 mg/kg for laryngeal mask placement or tracheal intubation and mechanical ventilation. Anaesthesia maintained with infusions of propofol 1–4 µg/mL and remifentanil 0.1–0.2 µg/kg/minute to keep anaesthesia depth measured as BIS 40–60. Comparator: CSA Participants received supplemental oxygen using a facemask. Sedation provided with sufentanil 0.1 µg/kg bolus and propofol 0.5–1.0 µg/mL and allowed to keep BIS > 70. Excluded medications: not reported
Outcomes	Primary outcome (specified) mRS (time frame: postprocedural 30 days)  Primary outcome (collected) Global disability measured by mRS 90 days after randomisation. Favourable neurological outcome defined as mRS 0–2  Secondary outcomes (specified) Change in NIHSS at 24 hours, 7 days (or at discharge), 30 days, and 3 months after randomisation  mTICI score before and after EVT Intraprocedural SBP, DBP, heart rate, and ETCO2 at 10‐minute intervals  All‐cause mortality up to 3 months after randomisation Incidence of complications up to 3 months after randomisation  Length of stay in the hospital or ICU after randomisation MOCA and MMSE assessed at 24 hours, 7 days (or at discharge), 30 days, and 3 months after randomisation  Rate of delirium measured by CAM after randomisation Secondary outcomes (collected) Change in NIHSS at 24 hours, 7 days after randomisation. NIHSS at discharge, 30 days, and 3 months after randomisation were not collected mTICI score after EVT Length of ICU stay mRS after 30 days (not reported at specified) All‐cause mortality and morbidity up to 3 months after EVT Complications during EVT: substantial movement, nausea or vomiting, hypoxaemia during the EVT, mortality after 90 days, vessel perforation, pulmonary infection Workflow time in minutes: symptoms to the door; door‐to‐arterial puncture; arterial puncture‐to‐reperfusion; symptoms‐to‐reperfusion MMSE, MOCA, and CAM (not collected)
Notes	Conflict of interest: (quote) "The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article". Funding: (quote) "The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The trial is funded by the Beijing Municipal Administration of Hospitals 'Youth Program' (reference number: QML20150508) and Beijing Municipal Administration of Hospitals Clinical Medicine Development of Special Funding Support (code number: ZYLX201708)". Protocol: NCT02677415
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Randomisation occurred when patients were sent to the interventional neuroradiology suite for EVT and were obtained through a purposely built web‐based program, stratified by the site of culprit's vessels (ICA or MCA) using permuted blocks". Comment: method for randomisation was described and seemed appropriate.
Allocation concealment (selection bias)	Unclear risk	Details were not fully described. Quote: "Patients were randomly allocated to receive either GA or CS in a 1 to 1 ratio".
Blinding of participants and personnel (performance bias)	High risk	Not described, but due to the nature of the interventions, we assumed that blinding of personnel was not possible.
Blinding of outcome assessment (detection bias)	Low risk	Quote: "we measured mRS at 90 days by the certified neurologists who were blinded to the group allocation".
Incomplete outcome data (attrition bias)	High risk	There were no losses. Crossover occurred in 4 (18.2%) participants from CSA to GA group.
Selective reporting (reporting bias)	Low risk	All prespecified outcomes were reported.
Other bias	Low risk	No evidence of other bias related to this study.