title: Severe methaemoglobinaemia treated with adjunctive hyperbaric oxygenation.
abstract: Methaemoglobinaemia results from exposure to oxidizing substances such as nitrates or nitrites. Iron within haemoglobin is oxidized from the ferrous to the ferric state, which blocks the transport of oxygen and carbon dioxide, with subsequent inhibition of the respiratory chain. We describe the case of a 23-year-old male suffering from severe methaemoglobinaemia of 68% after consumption of nitrites ('poppers') in association with considerable ethanol consumption. Toluidine-blue was administered as ﬁrst-line antidotal therapy immediately followed by hyperbaric oxygenation (HBOT). HBOT resulted in enhanced reduction of methaemoglobin, and rapid tissue re-oxygenation by the oxygen dissolved in plasma was provided, independent of the degree of methaemoglobinaemia. The patient recovered uneventfully and was discharged three days later. This case illustrates the potential of supportive HBOT as a time-saving therapeutic tool in this unusual situation, enabling a quick and sustained reduction in methaemoglobinaemia.
authors.affiliation: Division of Thoracic and Hyperbaric Surgery, Department of General Surgery, Medical University Graz, Auenbruggerplatz 29, 8036 Graz, Austria, Phone: +43-(0)316-385-13302, E-mail: jo.lindenmann@medunigraz.at.
authors.forename: Jörg
authors.initials: J
authors.lastname: Lindenmann
authors.affiliation: Division of Thoracic and Hyperbaric Surgery, Department of General Surgery, Medical University Graz, Austria.
authors.forename: Nicole
authors.initials: N
authors.lastname: Fink-Neuboeck
authors.affiliation: Department of Internal Medicine, Medical University Graz, Austria.
authors.forename: Gernot
authors.initials: G
authors.lastname: Schilcher
authors.affiliation: Division of Thoracic and Hyperbaric Surgery, Department of General Surgery, Medical University Graz, Austria.
authors.forename: Freyja Maria
authors.initials: FM
authors.lastname: Smolle-Juettner
mesh_terms: D000428:Alcohol Drinking / Q000009:adverse effects*; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000379:methods*; D008297:Male; D008708:Methemoglobinemia / Q000097:blood / Q000139:chemically induced / Q000628:therapy*; D009573:Nitrites / Q000506:poisoning; D019966:Substance-Related Disorders / Q000150:complications*; D055815:Young Adult
chemical_list: D009573:Nitrites
keywords: Hyperbaric oxygen therapy; case reports; drugs; hypoxia; neuroprotection; toxicity