What Researchers Did
Researchers measured cyanide levels in the blood of fire victims and other patients with carbon monoxide poisoning, before and after hyperbaric oxygen therapy, to see if the treatment changed cyanide concentrations.
What They Found
This clinical study of 37 patients with carbon monoxide intoxication found no significant change in whole blood cyanide concentration after hyperbaric oxygen therapy. Cyanide levels before treatment did not differ significantly between fire victims and non-fire CO patients (p equals 0.42), and the change in cyanide levels after treatment also did not differ significantly between the two groups (p equals 0.7). Plasma lactate levels before and after treatment likewise did not differ significantly between groups. Twelve of the 25 fire patients and one of the 12 non-fire patients had also received hydroxycobalamin before hyperbaric oxygen therapy.
Canadian Relevance
No direct Canadian connection identified.
Study Limitations
The study measured cyanide in only 37 patients with cyanide testing (compared against 12 controls), and some patients in both groups had already received a cyanide antidote before blood samples were taken, which could have affected the cyanide measurements and limits how clearly the results isolate the effect of hyperbaric oxygen therapy alone.