Treatment of smoke inhalation by hyperbaric oxygen

Five patients with smoke inhalation from house fires presented to the hospital in a comatose state. Carboxyhemoglobin levels were elevated in all five patients, mean=32% +/- 6. Arterial blood gases revealed the following means: pH 7.16 +/- 0.06; PCO2 35 mm HG +/- 10.5; HCO3 12.6 mEq/L +/- 0.07; base excess -16 mEq/L +/- 1.58; PO2 353 mm Hg +/- 149; O2 saturation 66% +/- 5.5. The patients were presumed to have both cyanide and carbon monoxide intoxication and were treated with the cyanide antidote kit and hyperbaric oxygen (HBO). Four of five patients awoke within 15 minutes of reaching maximum pressure and remained neurologically intact thereafter. The fifth patient died one week later. Cyanide blood levels drawn prior to treatment revealed a mean of 1.62 microgram/mL +/- 1.44. The highest cyanide level was 3.9 microgram/mL (the death) and the lowest 0.35 microgram/mL. We conclude that smoke inhalation can result in acute cyanide poisoning and that hyperbaric oxygen is a useful adjunct in the treatment of smoke inhalation.