Normobaric Hyperoxia Combined With Endovascular Treatment Based on Temporal Gradient: A Dose-Escalation Study

Area of Science:

• Neurology
• Emergency Medicine
• Critical Care

Background:

• Normobaric hyperoxia (NBO) demonstrates neuroprotective effects in acute ischemic stroke.
• Optimal NBO treatment duration in conjunction with endovascular treatment requires identification.

Purpose of the Study:

• To determine the most effective duration of NBO therapy when combined with endovascular treatment for acute ischemic stroke.
• To evaluate the impact of varying NBO durations on cerebral infarction volume and patient outcomes.

Main Methods:

• A single-center, randomized controlled trial involving 100 acute ischemic stroke patients undergoing endovascular treatment.
• Patients were assigned to four groups: control (4 hours oxygen at 1 L/min), NBO-2h (2 hours at 10 L/min), NBO-4h (4 hours at 10 L/min), and NBO-6h (6 hours at 10 L/min).
• Primary outcome: cerebral infarction volume at 72 hours. Safety outcome: 90-day mortality rate.

Main Results:

• The NBO-4h and NBO-6h groups showed significantly reduced 72-hour cerebral infarct volumes compared to the control group (P=0.011 and P=0.027, respectively).
• NBO-4h and NBO-6h groups demonstrated significant improvements in National Institutes of Health Stroke Scale scores at multiple time points.
• No significant differences were observed in 90-day mortality, symptomatic intracranial hemorrhage, or other severe adverse events among the groups.

Conclusions:

• Normobaric hyperoxia therapy for 4 and 6 hours is more effective than standard oxygen in reducing infarct volume for acute ischemic stroke patients undergoing endovascular treatment.
• Treatment effectiveness is duration-dependent, with 4-6 hours showing optimal results.
• Larger, multicenter studies are recommended to validate these findings.