Efficacy of inhaled hydrogen on neurologic outcomes after cerebral ischemia during cardiac arrestScientific Research
Efficacy of inhaled HYdrogen on neurological outcome following BRain Ischemia During post-cardiac arrest care (HYBRID II trial): study protocol for a randomized controlled trial
Hydrogen (HI) inhalation improves survival and neurological outcomes in an animal model of post-cardiac arrest syndrome (PCAS). A pilot study confirmed the feasibility and safety of HI in PCAS patients. The purpose of this study was to evaluate the efficacy of HI in patients with PCAS.
The Efficacy of Hydrogen Inhalation on Neurological Outcomes After Cerebral Ischemia Without Cardiac Care (HYBRID II) study was an investigator-initiated, randomized, double-blind, placebo-controlled study recruiting 360 comatose adults (Glasgow, IL). Coma score < 8) in patients resuscitated after out-of-hospital cardiac arrest of suspected cardiac cause. Patients will be randomly assigned (1:1) to the HI group or the control group. The patients in the HI group inhaled 2% hydrogen and 24%-50% oxygen, and the patients in the control group inhaled 24%-50% oxygen 18 hours after admission to mechanical ventilation. .Provides multidisciplinary follow-up according to the latest guidelines, including target temperature management (TTM) between 33°C and 36°C. The primary outcome of interest was the 90-day neurological outcome assessed using the Brain Performance Category (CPC) scale. Secondary outcomes of interest were 90-day survival and other neurological outcomes. This study will provide 80% power to detect a 15% change from 50% to 65% in the proportion of patients with favorable neurological outcome (CPC of 1 and 2), with an overall significance level of 0.05.
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The authors thank Dr. N. Kamatani for providing the statistical analysis design and assisting with preparation of the manuscript.
This trial will be funded by the Taiyo Nippon Sanso Corporation, including the provision of the gas (hydrogen or nitrogen) and the cost for cylinder delivery. Ordinary post-CA care, including TTM, will be insured by the Japanese health system. The funder of this study will not be involved in study design; data collection, management, analysis, or interpretation; the writing of the report; or the decision to submit the manuscript for publication.
Availability of data and materials
All de-identified individual participant data, study protocols, statistical analysis plans, and analytic codes will be shared with investigating members of the HYBRID Study Group. Shared data may be used for any type of analysis. Data will be available from the HYBRID Study Office at Keio University for 5 years immediately following publication