Inclusion/Exclusion Criteria


  1. Acute Ischemic Stroke in the following circulations that will be treated by EVT:
    1. ICA: Terminal “T” or “L-type” occlusion
    2. MCA: M1 or Proximal M2
    3. ACA: A1 or Proximal A2
  2. IV-tPA was delivered within 4.5 hours of symptom onset or last seen normal
  3. Ages: 18-90
  4. NIHSS: 6-30
  5. Time: Stroke onset to EVT (groin puncture): ≤ 16 hours
  6. Limited Infarct Core:
    1. For patients presenting ≤ 6 hours: ASPECTS is ≥ 6
    2. For patients present > 6 hours and ≤ 16 hours: EITHER ONE of the following:
      1. Ischemic Core < 70 mL, ratio of volume of penumbral tissue to infarct volume ≥ 1.8, and absolute volume of penumbral tissue of ≥ 15 mL
      2. Patients with NIHSS ≥ 10, infarct core of < 31 mL Patients with NIHSS ≥ 20, infarct core < 51 mL
    3. No significant pre-stroke disability (mRS must be ≤ 2).
    4. Negative serum or urine pregnancy test, if applicable.
    5. Subject willing/able to return for protocol required follow-up visits.
    6. Patient must be eligible for both CS and GA before randomization.
    7. Patient or Patient’s Legally Authorized Representative has given Informed Consent according to Good Clinical Practice (GCP) and/or local IRB policies



  1. GCS: < 8, need intubation, or transferred as intubated.
  2. Severe agitation or seizures that preclude safe vascular access.
  3. Loss of airway protective reflexes and/or vomiting on admission.
  4. Predicted or known difficult airway.
  5. Pre-existing neurological or psychiatric disease that would confound the neurological or functional evaluations, e.g. dementia.
  6. Presumed septic embolus, or suspicion of bacterial endocarditis.
  7. Currently participating or has participated in any investigational drug or device study within 30 days.
  8. Inability to follow-up for 90-day assessment.
  9. Known history of allergy to anesthesia drugs.
  10. Known history or family history of malignant hyperthermia.
  11. Determination by anesthesiologist and/or neurointerventionalist that randomized method of anesthesia is contraindicated for some reason; or operator declined.