Hyperbaric oxygen treatment for carbon tetrachloride poisoning

Carbon tetrachloride (CCl4) undergoes hepatic reductive metabolism to trichloromethyl (.CCl3) and peroxytrichloromethyl (CCl3OO.) free radicals, toxic intermediates which may initiate hepatocellular damage. Recent investigations have demonstrated a potential role for hyperoxia and hyperbaric oxygen as therapeutic interventions for CCl4 poisoning. Elevated oxygen concentrations in vitro and in vivo reduce lipid peroxidation and hepatotoxicity. In vivo studies of hyperbaric oxygen following administration of CCl4 in a rat model have shown improved survival and decreased hepatotoxicity. Case reports of human poisoning, with potentially lethal ingested doses of CCl4, also suggest a potential role for treatment with hyperbaric oxygen. Hyperoxia may act by altering the metabolism of CCl4. These studies and case reports support the recommendation that 100% normobaric and hyperbaric oxygen should be treatment considerations for CCl4 poisoning.