Overview
The goal of this clinical trial is to compare the effects of different concentrations of normobaric oxygen on early neurological improvement in acute ischemic stroke (AIS) patients receiving endovascular therapy (EVT). The main questions it aims to answer are:
- Evaluating the impact of normobaric high-concentration oxygen versus low-concentration oxygen on early neurological function after EVT.
- Evaluating the safety of high and low normobaric oxygen concentration in patients with ischemic stroke.
Participants will (1) receive EVT under general anesthesia; (2) be randomly assigned 1:1 to receive oxygen therapy with FiO2=80% or FiO2=30% through endotracheal intubation during the operation, and the gas flow rate was set at 4L /min.
Description
The optimal fraction of inspired oxygen (FiO2) during EVT under general anesthesia is currently uncertain. This is a randomized controlled trial (RCT) designed to assess the impact of normobaric high-concentration oxygen versus low-concentration oxygen on early neurological function following EVT. It is a prospective, open-label, parallel-design RCT planned to be conducted at Beijing Tiantan Hospital, Capital Medical University. It is anticipated that 200 cases of AIS patients undergoing EVT under general anesthesia will be consecutively enrolled from 2024 to 2026. Eligible participants will be randomly assigned in a 1:1 ratio. After general anesthesia induction, patients will receive continuous inhalation of oxygen with either FiO2=80% or FiO2=30% through endotracheal intubation until the end of the procedure, with a gas flow rate set at 4 L/min. The positive end-expiratory pressure (PEEP) is uniformly set to 5 cmH2O to balance its effect on pulmonary oxygen delivery. The primary outcome will be the occurrence of early neurological improvement (NIHSS score of 10 points 24±2 hours after EVT). Safety outcomes include potential adverse events such as site infection, three-month mortality, etc.
Eligibility
Inclusion Criteria:
- Age ≥18 years.
- Anterior circulation occlusive stroke was confirmed by CT angiography (CTA), magnetic resonance angiography (MRA) or digital subtraction angiography (DSA), and occlusions of the terminal internal carotid artery (ICA) or M1 segment of the middle cerebral artery (MCA) were involved.
- NIHSS score at admission: 6-25.
Exclusion Criteria:
- Stroke onset at 6-24 hours with a mismatched area < 15 ml was assessed by CT perfusion imaging (CTP).
- Significant dysfunction before stroke was defined as a modified Rankin scale (mRS) score ≥2.
- The condition was complicated by severe agitation and seizures.
- Evidence of intracranial hemorrhage at admission.
- Pulmonary disease complicated by impaired gas exchange.
- An oxygen mask or ventilator must be used before anesthesia to maintain a SpO2≥94%.
- Loss of airway protective reflex or vomiting aspiration upon admission.