{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T23:11:08Z","timestamp":1772752268261,"version":"3.50.1"},"reference-count":33,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2022,9,29]],"date-time":"2022-09-29T00:00:00Z","timestamp":1664409600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012669","name":"Natural Science Foundation Project of Chongqing, Chongqing Science and Technology Commission","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100012669","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurol."],"abstract":"<jats:sec><jats:title>Background<\/jats:title><jats:p>Post-cardiac arrest (CA) brain injury is the main cause of death in patients resuscitated from CA. Previous studies demonstrated that hydrogen inhalation mitigates post-CA brain injury. However, factors affecting the efficacy of hydrogen remain unknown. In the present study, we investigated the influence of oxygen concentration and targeted temperature on neuroprotective effect in a CA rat model of ventricular fibrillation (VF).<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Cardiopulmonary resuscitation (CPR) was initiated after 7 min of untreated VF in adult male Sprague\u2013Dawley rats. Immediately following successful resuscitation, animals were randomized to be ventilated with 21% oxygen and 79% nitrogen (21%O<jats:sub>2<\/jats:sub>); 2% hydrogen, 21% oxygen, and 77% nitrogen (2%H<jats:sub>2<\/jats:sub> + 21%O<jats:sub>2<\/jats:sub>); 2% hydrogen, 50% oxygen, and 48% nitrogen (2%H<jats:sub>2<\/jats:sub> + 50%O<jats:sub>2<\/jats:sub>); or 2% hydrogen and 98% oxygen (2%H<jats:sub>2<\/jats:sub> + 98%O<jats:sub>2<\/jats:sub>) for 3 h. For each group, the target temperature was 37.5\u00b0C for half of the animals and 35.0\u00b0C for the other half.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>No statistical differences in baseline measurements and CPR characteristics were observed among groups. For animals with normothermia, 2%H<jats:sub>2<\/jats:sub> + 50%O<jats:sub>2<\/jats:sub> (123 [369] vs. 500 [393], <jats:italic>p<\/jats:italic> = 0.041) and 2%H<jats:sub>2<\/jats:sub> + 98%O<jats:sub>2<\/jats:sub> (73 [66] vs. 500 [393], <jats:italic>p<\/jats:italic> = 0.002) groups had significantly lower neurological deficit scores (NDSs) at 96 h and significantly higher survival (75.0 vs. 37.5%, <jats:italic>p<\/jats:italic> = 0.033 and 81.3 vs. 37.5%, <jats:italic>p<\/jats:italic> = 0.012) than 21%O<jats:sub>2<\/jats:sub> group. For animals with hypothermia, no statistical difference in NDS among groups but 2%H<jats:sub>2<\/jats:sub> + 98%O<jats:sub>2<\/jats:sub> has significantly higher survival than the 21%O<jats:sub>2<\/jats:sub> group (93.8 vs. 56.3%, <jats:italic>p<\/jats:italic> = 0.014).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>In this CA rat model, inhaling 2% hydrogen combined with a high concentration of oxygen improved 96-h survival, either under normothermia or under hypothermia.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fneur.2022.996112","type":"journal-article","created":{"date-parts":[[2022,9,29]],"date-time":"2022-09-29T10:05:51Z","timestamp":1664445951000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["Influence of oxygen concentration on the neuroprotective effect of hydrogen inhalation in a rat model of cardiac arrest"],"prefix":"10.3389","volume":"13","author":[{"given":"Jianjie","family":"Wang","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yiming","family":"Shen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jingru","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bihua","family":"Chen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Changlin","family":"Yin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongqin","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2022,9,29]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"970","DOI":"10.1016\/S0140-6736(18)30472-0","article-title":"Out-of-hospital cardiac arrest: current concepts","volume":"391","author":"Myat","year":"2018","journal-title":"Lancet."},{"key":"B2","doi-asserted-by":"publisher","first-page":"61","DOI":"10.1186\/s13054-020-2773-2","article-title":"The global survival rate among adult out-of-hospital cardiac arrest patients who received cardiopulmonary resuscitation: a systematic review and meta-analysis","volume":"24","author":"Yan","year":"2020","journal-title":"Crit Care."},{"key":"B3","doi-asserted-by":"publisher","first-page":"1393","DOI":"10.1007\/s00134-021-06548-2","article-title":"Brain injury after cardiac arrest: pathophysiology, treatment, and prognosis","volume":"47","author":"Sandroni","year":"2021","journal-title":"Intensive Care Med."},{"key":"B4","doi-asserted-by":"publisher","first-page":"220","DOI":"10.1016\/j.resuscitation.2021.02.012","article-title":"European resuscitation council and European society of intensive care medicine guidelines 2021: post-resuscitation care","volume":"161","author":"Nolan","year":"2021","journal-title":"Resuscitation."},{"key":"B5","doi-asserted-by":"publisher","first-page":"175","DOI":"10.21037\/atm-20-7853","article-title":"2020 expert consensus statement on neuro-protection after cardiac arrest in China","volume":"9","author":"Ma","year":"2021","journal-title":"Ann Transl Med."},{"key":"B6","doi-asserted-by":"publisher","first-page":"S465","DOI":"10.1161\/CIR.0000000000000262","article-title":"Part 8: post-cardiac arrest care: 2015 American heart association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care","volume":"132","author":"Callaway","year":"2015","journal-title":"Circulation."},{"key":"B7","doi-asserted-by":"publisher","first-page":"2283","DOI":"10.1056\/NEJMoa2100591","article-title":"TTM2 trial investigators. 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