Citation

Timmons P. BMJ Case Rep. 2024; 17(5): e259384.

Copyright

(Copyright © 2024, BMJ Publishing Group)

DOI

10.1136/bcr-2023-259384

PMID

38806397

Abstract

We present a case of a man in his late 40s presenting with generalised tonic-clonic seizures and profound methaemoglobinaemia shortly after inadvertent ingestion of amyl nitrite. Arterial blood gas analysis demonstrated methaemoglobin levels exceeding the upper detection threshold of our analyser, accompanied with profound cyanosis despite apparent oxygen saturations of 94%. Prompt administration of intravenous methylene blue led to a rapid and complete recovery. This case highlights the importance of swift recognition and treatment of methaemoglobinaemia particularly when the precipitating factor may be unknown at the time of presentation. This case also demonstrates the potential limitations of bedside blood gas analysers in diagnosis.

Language: en

Keywords

*Amyl Nitrite/poisoning/adverse effects; *Methemoglobinemia/chemically induced/diagnosis; *Methylene Blue/therapeutic use; *Seizures/chemically induced; Adult; Blood Gas Analysis; Emergency medicine; Humans; Male; Poisoning; Toxicology