Commentary - The non-utility of HBO for CO poisoning?

Journal Club

CJEM 2000;2(1):24

The optimal time window for HBO after CO poisoning has yet to be determined, but the current standard is within 6 hours of exposure, and benefit seems most likely if treatment is started much earlier, although this is not known. In the Scheinkestel study, most patients had severe poisoning and the median time to treatment was over 7 hours. Based on severity and time to treatment, much CNS damage could have occurred prior to the administration of HBO. In other words, many of these patients may have been (relatively) beyond help, therefore unable to benefit from the treatment administered. In addition, most of the patients in this study were depressed and suicidal. Such patients score poorly on the neuropsychological tests used to evaluate outcomes, and this may have influenced the study results.

Current recommendations of the Undersea and Hyperbaric Medical Society (UHMS) and European Committee for Hyperbaric Medicine are that hyperbaric oxygen is indicated for patients who experience neurological or cardiac symptoms after CO exposure. These recommendations will likely not change based on this single study.