Methemoglobinemia in Emergency Medicine Treatment & Management
- Author: David C Lee, MD; Chief Editor: Asim Tarabar, MD more...
Prehospital Care
Prehospital care includes administration of supplemental oxygen and removal of the offending oxidizing agent.
Emergency Department Care
Clinical recognition is paramount, as patients may have only vague complaints. Treatment is determined by symptomatology. Healthy asymptomatic patients without evidence of end-organ damage may require only observation.
- Patients with coronary artery disease or anemia may require therapeutic intervention at lower methemoglobin levels (eg, 10%) than a typical patient would, especially if end-organ dysfunction (eg, cardiac ischemia) is present.
- Supplemental oxygen
- Methylene blue is the first-line antidotal agent. Hyperbaric oxygen therapy or packed RBC exchange transfusions are alternative therapies for patients who are not candidates for methylene blue.
- Dermal decontamination (eg, water rinse, soap scrub, water rinse again)
- GI decontamination (eg, gastric lavage, activated charcoal administration)
- Investigational agents and therapies have no proven benefitsin the treatment of methemoglobinemia (eg, vitamin C, an antioxidant, and N- acetylcysteine, a cellular antioxidant)
Consultations
An American Association of Poison Control Centers (AAPCC)-certified regional poison control center or a medical toxicologist should be consulted in life-threatening cases.
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