6/28/23, 11:06 PM HYBRID II Pathway Feedback Search Clinical Topics Home Studies HYBRID II HYBRID II Disease Cardiac arrest Trial question What is the role of inhaled hydrogen gas in patients with coma following cardiogenic out-of- hospital cardiac arrest? Study design Multi-center Double blinded RCT Population Characteristics of study participants 19.0% female N = 73 81.0% male 73 patients (14 female, 59 male) Inclusion criteria: patients aged 20-80 years with coma following cardiogenic out-of-hospital cardiac arrest Key exclusion criteria: known pre-arrest cerebral performance category score of 3 or 4; known treatment limitations; do not resuscitate order; trauma-associated out-of-hospital cardiac arrest; oxygen saturation < 94% with 50% oxygen inhalation Interventions N=39 hydrogen gas (inhalation of 2% hydrogen gas for 18 hours) N=34 control (inhalation of titrated oxygen gas for 18 hours) Primary outcome Cerebral performance category of 1 or 2 at day 90 56.0 % 56 https://web.pathway.md/studies/recO2mVzype2pkozx 1/2 6/28/23, 11:06 PM HYBRID II Pathway 42.0 % 39 28.0 % 14.0 % No significant difference 0.0 % Hydrogen gas Control No significant difference in cerebral performance category of 1 or 2 at day 90 (56% vs. 39%; RR 0.72, 95% CI 0.46 to 1.13) Secondary outcomes Significant decrease in median mRS score at day 90 (1 vs. 5; AD -4, 95% CI -7.04 to -0.96) Significant increase in survival at day 90 (85% vs. 61%; RR 2.5, 95% CI 1.09 to 5.88) Significant increase in mRS score of 0 (46% vs. 21%; RR 2.18, 95% CI 1.04 to 4.56) Safety outcomes No significant difference in adverse events and serious adverse events. Conclusion In patients aged 20-80 years with coma following cardiogenic out-of-hospital cardiac arrest, hydrogen gas were not superior to control with respect to cerebral performance category of 1 or 2 at day 90. Reference Tomoyoshi Tamura, Masaru Suzuki, Koichiro Homma et al. Efficacy of inhaled hydrogen on neurological outcome following brain ischaemia during post-cardiac arrest care (HYBRID II): a multi-centre, randomised, double-blind, placebo-controlled trial. EClinicalMedicine. 2023 Mar 17;58:101907. Open reference URL https://web.pathway.md/studies/recO2mVzype2pkozx 2/2