Methemoglobinemia as a cause of coma

✍ Scribed by LeRoy Caudill; Jay Walbridge; Gloria Kuhn

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 361 KB
• Volume: 19
• Category: Article
• ISSN: 1097-6760
• DOI: 10.1016/s0196-0644(05)82476-x

✦ Synopsis

A 50-year-old man presented to the emergency department in a coma with fixed and dilated pupils. Skin and mucous membranes were noted to be an ashen grey color. Initial vital signs were blood pressure of 104/70 mm Hg; pulse, 110; and respirations, 12. Initial arterial blood gases were pH of 7.25; PaCO2, 26.6 mm Hg; PaO2, 22.1 mm Hg; oxygen saturation, 15.2%; and methemoglobin level, 81.5%. Venous and arterial blood samples were chocolate brown, and it was noted that the color did not change when 100% oxygen was bubbled through the blood. Methylene blue 140 mg was given intravenously, and the patient gradually became more responsive. He was discharged three days later with no neurologic deficits. A comprehensive literature search revealed no reported cases of complete patient recovery with this high a methemoglobin level.