Fatal Methaemoglobin Intoxication Following Ketamine Infusion in a Depressed MELAS Patient: A Possible Association?
Case Reports in Critical Care January 1, 2025 J. Finsterer
A 32-year-old woman with MELAS syndrome died suddenly 1–12 hours after a single ketamine infusion for depression and PTSD. Autopsy showed methemoglobin at 71% of hemoglobin, far above the normal 0–2% range. The authors speculate that ketamine may have triggered fatal methemoglobinemia by reducing ATP production and impairing methemoglobin reductase, a mitochondrial toxic effect. They conclude that ketamine should be used cautiously in MELAS patients, especially those with a seizure history, and that such patients require careful monitoring during and after infusion.