Inclusion Criteria- Patients with AIS scheduled to receive emergency endovascular treatment, older than 18; the onset time is within 12 hours.
Exclusion Criteria- Radiological ambiguity concerning infarction and vessel occlusion.
- Additional intracerebral hemorrhage.
- Posterior circulation infraction.
- Coma on admission (Glasgow coma score less than 8).
- NIHSS less than 10.
- Severe agitation or seizures on admission.
- Obvious loss of airway protective reflexes and/or vomiting on admission.
- Being intubated before treatment on admission.
- Known allergy to anesthetic or analgesic.