Normobaric Hyperoxia Combined With Intravenous Thrombolysis for Acute Ischemic Stroke (OPENS-3)

Inclusion Criteria: Age≥18 years; The time from onset to randomization is within 4.5 hours of onset; The clinical diagnosis is acute ischemic stroke (the criteria followed the Chinese Guidelines for the Diagnosis and Treatment of Acute Ischemic Stroke 2018); Baseline NIHSS (at the time of randomization) should be ≥5 and ≤25 points; Pre-stroke mRS score≤1 points; Informed consent from the patient or surrogate. Exclusion Criteria: Intracranial hemorrhage (including parenchymal hemorrhage, intraventricular hemorrhage, subarachnoid hemorrhage, subdural/extradural hematoma, etc.); Past history of intracranial hemorrhage; Rapid neurological function improvement, NIHSS score less than 5 points; Presence of proximal arterial occlusion on computed tomographic angiography(CTA)/magnetic resonance angiography(MRA) (e.g., intracranial internal carotid artery(ICA), middle cerebral artery(MCA)-M1, and vertebrobasilar arteries); Massive anterior cerebral infarction identified by CT or MRI (ASPECT < 6 or lesions larger than one third of the territory of the middle cerebral artery); Intended to proceed endovascular treatment; Pregnant women, or planning to become pregnant during the trial; A history of severe head trauma or stroke within 3 months; A history of intracranial or spinal surgery within 3 months; A history of gastrointestinal or urinary bleeding within 3 weeks; two weeks of major surgery; Arterial puncture was performed at the hemostasis site that was not easily compressed within 1 week; Active visceral bleeding; Intracranial tumors, large intracranial aneurysms; Aortic arch dissection was found; Severe, sustained hypertension (Systolic Blood Pressure >185 mmHg or Diastolic Blood Pressure >110 mmHg); Baseline blood glucose of <50mg/dL (2.78 mmol) or >400mg/dL (22.20 mmol); Oral warfarin anticoagulant with international normalized ratio(INR)>1.7 or prothrombin time(PT)>15 s; Heparin treatment was received within 24 h; Thrombin inhibitors or factor Xa inhibitors were used within 48 h; Propensity for acute bleeding, including platelet counts of less than 100×109/ L or otherwise; Hereditary or acquired bleeding constitution; Onset with seizures; Severe liver and kidney dysfunction; Active and chronic obstructive pulmonary disease or acute respiratory distress syndrome; Patients with anemia or polycythemia vera or other situations that require urgent oxygen inhalation; Patients with upper gastrointestinal bleeding or nausea or vomiting so that they cannot cooperate with the mask to inhale oxygen; Life expectancy < 1 year; Patients who could not complete the 90-day follow-up; Participation in other clinical trials within 3 months prior to screening; Unsuitability or participation in this study as judged by the Investigator may result in subjects being exposed to greater risk.