Fujita M, Todani M, Ajimi Y, Yatabe T, Yokobori S, Araki M, Chihara N, Nagayama M, Sakamoto T, Tsuruta R, Japan Resuscitation Council (JRC) Neuroresuscitation Task Force and the Guidelines Editorial Committee, et al.
Acute medicine & surgery. Date of publication 2026 Jan 28;volume 13(1):e70114.
1. Acute Med Surg. 2026 Jan 28;13(1):e70114. doi: 10.1002/ams2.70114. eCollection
2026 Jan-Dec.
Evaluating the Efficacy of Hyperbaric Oxygen Therapy for Acute Carbon Monoxide
Poisoning: A Systematic Review and Meta-Analysis.
Fujita M(1), Todani M(1), Ajimi Y(2), Yatabe T(3), Yokobori S(4), Araki M(5),
Chihara N(6), Nagayama M(7)(8)(9), Sakamoto T(10), Tsuruta R(1); Japan
Resuscitation Council (JRC) Neuroresuscitation Task Force and the Guidelines
Editorial Committee.
Collaborators: Kobata H, Kondo Y, Yoshimura H, Kawamoto M, Wakasugi M, Yamagami
H, Nakamoto H, Hoshiyama E, Todo K, Togawa M, Kurihara M, Moriya T, Nakae R,
Uchida H, Yang S, Iwase M.
Author information:
(1)Emergency and Critical Care Medicine Yamaguchi University Graduate School of
Medicine Ube Yamaguchi Japan.
(2)Department of Emergency Medicine Teikyo University School of Medicine
Itabashi-Ku Tokyo Japan.
(3)Emergency Department Nishichita General Hospital Tokai Aichi Japan.
(4)Department of Emergency and Critical Care Medicine Nippon Medical School
Bunkyo-Ku Tokyo Japan.
(5)Department of Neurology Kawakita General Hospital Tokyo Japan.
(6)Division of Neurology Kobe University Hospital Kobe Japan.
(7)Department of Neurology International University of Health and Welfare Narita
Hospital Narita Chiba Japan.
(8)Department of Critical Care Medicine International University of Health and
Welfare Narita Hospital Narita Chiba Japan.
(9)Center for Preventive Medicine International University of Health and Welfare
Narita Hospital Narita Chiba Japan.
(10)Showa General Hospital Kodaira Tokyo Japan.
Erratum in
Acute Med Surg. 2026 Sep 14;13(1):e70162. doi: 10.1002/ams2.70162.
Comment in
Acute Med Surg. 2026 Jul 11;13(1):e70142. doi: 10.1002/ams2.70142.
Acute Med Surg. 2026 Jul 11;13(1):e70147. doi: 10.1002/ams2.70147.
Comment on
Acute Med Surg. 2026 Jul 11;13(1):e70142. doi: 10.1002/ams2.70142.
Acute Med Surg. 2026 Jul 11;13(1):e70147. doi: 10.1002/ams2.70147.
AIM: To reassess the efficacy of hyperbaric oxygen (HBO) therapy for acute
carbon monoxide (CO) poisoning through a systematic review and meta-analysis,
including a subgroup analysis of treatment pressures exceeding 2.5 atm absolute
(ATA).
METHODS: We conducted a systematic review and meta-analysis of randomized
controlled trials (RCTs) evaluating HBO therapy for acute CO poisoning. A
literature search was performed in MEDLINE, CENTRAL, and Ichushi-Web databases,
focusing on RCTs published up to June 2024. Only adult patients (≥ 18 years)
were included, and studies were screened following PRISMA guidelines. Data
extraction and quality assessment were conducted by two independent reviewers
using the Cochrane risk of bias tool and the GRADE approach. Statistical
analysis used a random effects model, with outcomes expressed as odds ratios
(OR) and 95% confidence intervals (CI).
RESULTS: Six studies were included, and no significant benefit of HBO therapy
was observed in terms of reducing mortality or improving neurological outcomes.
The subgroup analysis of HBO at ≥ 2.5 ATA also showed no significant advantage
over control treatments. Moderate to significant heterogeneity was found across
included studies, and the quality of evidence was rated as low to very low.
CONCLUSIONS: The efficacy of HBO therapy, even at ≥ 2.5 ATA, for improving
outcomes in acute CO poisoning remains unproven. Despite these findings, HBO
therapy may still hold potential benefits that require further exploration.
High-quality, multicenter RCTs are necessary to better define its role in the
treatment of CO poisoning.
TRIAL REGISTRATION: UMIN Clinical Trials Registry: UMIN000054641.
© 2026 The Author(s). Acute Medicine & Surgery published by John Wiley & Sons
Australia, Ltd on behalf of Japanese Association for Acute Medicine.
DOI: 10.1002/ams2.70114
PMCID: PMC12853008
PMID: 41624627
Conflict of interest statement: Dr. Shoji Yokobori is an Editorial Board member
of AMS Journal and a co‐author of this article. To minimize bias, he was
excluded from all editorial decision‐making related to the acceptance of this
article for publication. The remaining authors declare no conflicts of interest
for this article.
