Maurice 2022.

Study characteristics
Methods	Setting: single‐centre, France Design: RCT, 2 arms, parallel assignment, open‐label single‐blind Start date: 27 July 2016 (reported in protocol) Completion date: August 2020 (reported in protocol)
Participants	351 men and woman aged ≥ 18 years randomised: experimental (GA) = 174, comparator (CSA) = 177 Received allocated intervention: GA = 171: 3 did not receive allocated intervention and received CSA (2 contraindication to GA and 1 impossible intubation); CSA = 176: 8 did not receive allocated intervention and received GA (7 switched to GA due to: excessive agitation = 3, catheter failure = 2, acute hypoxia = 1, neurological status and respiratory arrest = 1), and 1 directly received GA due to contraindication to CSA; consent withdrawal: GA = 5 and CSA = 1; lost to follow‐up: GA = 3 and CSA = 1 345 participants were analysed: GA = 169 and CSA = 176 Mean age: 72 years (range: 60–85 years) Gender (men/women): 188/157 Mean NIHSS score: 16 (score range: 10–22) Localisation of stroke in left hemisphere: GA = 84 (50%) and CSA = 90 (51%) 8 (4%) participants converted from CSA to GA Received IV r‐tPA before EVT: GA = 111 (66%) and CSA = 114 (65%)  Diagnostic criteria: AIS with LVO in anterior cerebral circulation Inclusion criteria Aged ≥ 18 years admitted to the participating centre Occlusion of a large vessel in the anterior cerebral circulation Undergoing EVT for stroke Benefiting from the health insurance system Signed informed consent from the participant or legal next of kin Exclusion criteria Pregnant or breastfeeding women Already intubated and mechanical ventilated before inclusion in the study Intracerebral haemorrhage associated with the ischaemic stroke Contraindications to CSA: GCS < 8, agitation not allowing the participant to stay still during procedure, and deglutition disorders Contraindications to succinylcholine, hyperkalaemia, and allergy BMI > 35 kg/m² Allergy to 1 of the anaesthetic drugs Uncontrolled hypotension Life‐threatening comorbidity Adults legally protected (under judicial protection, guardianship, or supervision) and people deprived of their liberty Unable to walk prior to stroke
Interventions	Experimental: GA Received etomidate 0.25–0.4 mg/k) and then target‐controlled infusion propofol (maximum target, 4 μg/mL) and target‐controlled infusion remifentanil 0.5–4 ng/mL and succinylcholine 1 mg/kg. Muscle relaxant reinjection was authorised as needed Comparator: CSA Received target‐controlled infusion remifentanil (maximum target, 2 ng/mL) and LA with lidocaine 10 mg/mL (maximum 10 mL). Oxygen administered only if oxygen saturation measured by pulse oximetry ≤ 96%. Respiratory rate and capnography monitored Conversion from CSA to GA was standardised and allowed in the following situations: agitation or restlessness not allowing the EVT; vomiting not allowing the EVT; GCS < 8; deglutition disorders, severe hypoxaemia with oxygen saturation measured by pulse oximetry at < 96% with oxygen being delivered via high‐concentration mask (maximum 10 L/minute), respiratory rate > 35/minute, clinical signs of respiratory exhaustion
Outcomes	Primary outcome (specified) Neurological outcome assessed with mRS 3 months after the EVT. Success was an mRS ≤ 2. mRS assessed by trained research nurse blinded to randomisation group. Additional exploratory analysis of the primary endpoint performed to assess treatment effects according to baseline NIHSS (≤ 14 or > 14) and the administration or not of IV thrombolysis Primary outcome (collected) Neurological outcome assessed by mRS score 2–6 months after EVT. Success was an mRS score ≤ 2. An additional exploratory analysis of the primary endpoint was performed to assess treatments effects according to baseline NIHSS score (≤ 14 or > 14) and the administration or not of IV thrombolysis Secondary outcomes (specified) Time between the beginning of the clinical symptoms and last angiography Time between arrival of participant at stroke centre and beginning of EVT (time of punction) Quality of recanalisation after EVT evaluated by the neuroradiologist (not blinded). A good‐quality recanalisation corresponded to mTICI 2b or 3 NIHSS score at day 1 (day after the EVT) and day 7 (or the day the participant left the hospital if scheduled before day 7) Complications during the procedure (dissection, rupture of the artery, and thrombus in another territory) Mortality rate 3 months after the EVT Number of hypotension or hypertension events during procedure and first 24 hours after procedure (hypotension defined as SBP < 140 mmHg or a drop of the MBP ≥ 40%, hypertension defined as SBP > 185 mmHg or DBP > 110 mmHg) Number of participants who received noradrenaline Number of conversion of CSA to GA Secondary outcomes (collected) Time between beginning of clinical symptoms and last angiography Time from stroke onset to groin puncture (not reported in protocol) Time from arrival in stroke centre to groin puncture Technical failure of EVT (defined as failure of arterial puncture or catheterisation) (not reported in protocol) Reperfusion results evaluated by neuroradiologist (good reperfusion corresponded to a modified treatment in Cerebral Ischemia Scale score of 2b or 3)  NIHSS score at day 1 (i.e. day after EVT) and day 7 (or day participant left hospital if scheduled before day 7) Complications during procedure (dissection, rupture of the artery, thrombus in another territory) Mortality rate 3 months after EVT Number of hypotensive or hypertensive events during procedure and first 24 hours after procedure (hypotension defined as SBP < 140 mmHg or a decrease in the MAP ≥ 40%; hypertension defined as SBP > 185 mmHg or DBP > 110 mmHg)  Number of participants who received noradrenaline Number of conversions from CSA to GA
Notes	Conflicts of interest: quote "Dr. Beloeil received speaking fees from AbbVie (Chicago, Illinois) and Aspen Pharmacare (Durban, South Africa) and is a member of an expert board for Orion Pharma (Espoo, Finland). The other authors declare no competing interests". Funding: quote "The GASS trial was supported by funding from the French Ministry of Health (Paris, France; National Clinical Research Hospital Program, 2015). The funding sources had no role in the trial design, trial conduct, data handling, data analysis, or writing and publication of the manuscript". Protocol: NCT02822144
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "randomization was centralized and computer generated, and each patient was given a unique randomization number (patient code)".
Allocation concealment (selection bias)	Low risk	Quote: "patients underwent randomization in a 1:1 ratio to undergo either general anesthesia or conscious sedation".
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)	Unclear risk	Quote: "the modified Rankin score was assessed by trained research nurses blinded to the randomization group". Comment: the author did not report blinding of secondary outcomes.
Incomplete outcome data (attrition bias)	High risk	4 lost to follow‐up. Crossover in 3 participants from CSA to GA and 8 participants from GA to CSA but were analysed as ITT. Consent withdrawal occurred in 5 participants in GA arm and 1 participant in CSA arm and excluded from ITT. Comment: the number of participants lost to follow‐up and consent withdrawal was considerable and generated an imbalance between groups.
Selective reporting (reporting bias)	High risk	A high number of participants had the mRS score evaluated between 2 and 6 months (GA = 96% and CSA = 94%) and 6% of participants had the mRS were evaluated after 6 months. Comment: the variations in the time of mRS score evaluation might affect the neurological outcomes.
Other bias	Low risk	No evidence of other bias related to this study.