Oxygen Concentration Target in Stroke Endovascular Treatment (Oxy-TARGET)

Capital Medical University

Status: Enrolling

Conditions: Ischemic Stroke

Treatments: Other: Normobaric low-concentration oxygen; Other: Normobaric high-concentration oxygen

Study type: Interventional

Funder types: Other

Identifiers

NCT06224426

zkd20231121

Details and patient eligibility

About

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.

Full 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.

Enrollment: 200 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Inclusion criteria

1. Age ≥18 years.
2. Anterior circulation occlusive stroke is confirmed by CT angiography (CTA), magnetic resonance angiography (MRA) or digital subtraction angiography (DSA), and occlusions of intracranial internal carotid artery (ICA) or M1 segment of the middle cerebral artery (MCA) were involved.
3. NIHSS score at admission: 6-20.
4. Randomization can be completed within 24 hours after stroke onset.

Exclusion criteria

1. Stroke onset within 6-24 hours with a CT perfusion imaging (CTP)-assessed mismatched area<15 ml.
2. Presence of anemia, defined as hemoglobin levels o below 120 g/L in men and below 110 g/L in women.
3. Pre-stroke modified Rankin scale (mRS) score ≥2.
4. Complicated by severe agitation and seizures.
5. Evidence of intracranial hemorrhage at admission.
6. Presence of chronic obstructive pulmonary disease, asthma, or other respiratory conditions, or requirement for daily supplemental oxygen or mechanical ventilation.
7. Baseline arterial blood gas analysis indicating impaired gas exchange: PaO2 < 60 mmHg on room air, or oxygenation index (PaO2/FiO2) < 300 mmHg with supplemental oxygen.
8. Emergency chest CT reveals significant pulmonary parenchymal infection.
9. An oxygen mask or ventilator must be used before anesthesia to maintain a SpO2≥94%.
10. Loss of airway protective reflex or vomiting aspiration upon admission.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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200 participants in 2 patient groups

Normobaric high-concentration oxygen (NBHO) group

Experimental group

Description:

After preoxygenating (FiO2=100%, 6 L/min) with a face mask for 3 min, patients will be sequentially administered intravenous sufentanil 0.2 µg/kg followed by propofol 2 mg/kg. Once the eyelash reflex was absent, all patients received 0.6 mg/kg rocuronium, with an endotracheal tube inserted approximately 90 seconds later. Mechanical ventilation is set to volume-controlled ventilation (VCV) mode, fresh gas flow 4 L/min, tidal volume (Vt) 6-8 ml/kg, respiratory rate (RR) 12-14 breaths/min, and positive end-expiratory pressure (PEEP) 5 cmH2O. End-tidal carbon dioxide (PetCO2) will be continuously monitored, maintaining it between 35-40 mmHg. Based on group allocation, the NBHO group will adjust the FiO2 at 80% throughout the surgery. Anesthesia will be maintained through total intravenous anesthesia, continuously infusing remifentanil 0.05-0.1 µg/kg/min and propofol 4-6 mg/kg/min, with intermittent 10 mg rocuronium as needed.

Treatment:

Other: Normobaric high-concentration oxygen

Normobaric low-concentration oxygen (NBLO) group

Experimental group

Description:

After preoxygenating (FiO2=100%, 6 L/min) with a face mask for 3 min, patients will be sequentially administered intravenous sufentanil 0.2 µg/kg followed by propofol 2 mg/kg. Once the eyelash reflex was absent, all patients received 0.6 mg/kg rocuronium, with an endotracheal tube inserted approximately 90 seconds later. Mechanical ventilation is set to volume-controlled ventilation (VCV) mode, fresh gas flow 4 L/min, tidal volume (Vt) 6-8 ml/kg, respiratory rate (RR) 12-14 breaths/min, and positive end-expiratory pressure (PEEP) 5 cmH2O. End-tidal carbon dioxide (PetCO2) will be continuously monitored, maintaining it between 35-40 mmHg. Based on group allocation, the NBLO group will adjust the FiO2 at 30% throughout the surgery. Anesthesia will be maintained through total intravenous anesthesia, continuously infusing remifentanil 0.05-0.1 µg/kg/min and propofol 4-6 mg/kg/min, with intermittent 10 mg rocuronium as needed.

Treatment:

Other: Normobaric low-concentration oxygen