A case of rapid onset methaemoglobinaemia associated with local anaesthetic use.

Methaemoglobinaemia is a rare but serious condition which can arise due to the administration of local anaesthetic agents. A 36-year-old woman with metastatic oesophageal adenocarcinoma experienced a rapid onset of methaemoglobinaemia following airway topicalisation with lidocaine and benzocaine sprays for bronchoscopy. The patient was treated with supplementary oxygen, non-invasive respiratory support, methylene blue and ascorbic acid. Early diagnosis and timely treatment of methaemoglobinaemia can result in rapid clinical improvement and prevent long-term complications.