eMedicine Specialties > Emergency Medicine > Toxicology

Methemoglobinemia: Follow-up

Author: David C Lee, MD, Research Director, Department of Emergency Medicine, Associate Professor, North Shore University Hospital and New York University Medical School
Coauthor(s): Kathy L Ferguson, DO, Attending Physician, Department of Emergency Medicine, New York Hospital of Queens, Queens, New York
Contributor Information and Disclosures

Updated: Jul 15, 2009

Follow-up

Further Inpatient Care

  • Admit all symptomatic patients with abnormal methemoglobin levels.
  • Admit all patients who require methylene blue treatment to an intensive care unit.

Complications

  • End-organ damage (eg, myocardial infarction, seizure, coma, death)

Prognosis

  • For minor cases of methemoglobinemia, the prognosis is very favorable.
  • In severe cases, prognosis is determined by the degree of anoxic end-organ damage.

Patient Education

  • Patients who develop methemoglobinemia from oxidant stress of pharmaceutical agents should be warned of other potent oxidant compounds.
  • Patients who develop methemoglobinemia secondary to environmental exposure require a meticulous workup to prevent re-exposure of the offending agent. All workplace or household members should be evaluated.

Miscellaneous

Medicolegal Pitfalls

  • The major pitfall is the misdiagnosis or the lack of recognition of this syndrome. Since initial symptoms can be vague, it easily can be mistaken for a common "garden variety" adverse drug event.

Special Concerns

  • Methylene blue may be ineffective, or even deleterious, in certain situations, including the following:
    • History of G-6-PD deficiency
    • Persistent absorption of offending oxidant toxin
    • Excessive methylene blue administration (ie, discolors skin and produces methemoglobinemia itself)
    • NADPH methemoglobin reductase (ie, diaphorase II) deficiencies
    • Presence of an abnormal hemoglobin (ie, hemoglobin M)
    • Presence of sulfhemoglobinemia
 


More on Methemoglobinemia

Overview: Methemoglobinemia
Differential Diagnoses & Workup: Methemoglobinemia
Treatment & Medication: Methemoglobinemia
Follow-up: Methemoglobinemia
Multimedia: Methemoglobinemia
References
[ CLOSE WINDOW ]

References

  1. Moore TJ, Walsh CS, Cohen MR. Reported adverse event cases of methemoglobinemia associated with benzocaine products. Arch Intern Med. Jun 14 2004;164(11):1192-6. [Medline].

  2. Ash-Bernal R, Wise R, Wright SM. Acquired methemoglobinemia: a retrospective series of 138 cases at 2 teaching hospitals. Medicine (Baltimore). Sep 2004;83(5):265-73. [Medline].

  3. Conkling PR. Brown blood: understanding methemoglobinemia. N C Med J. Mar 1986;47(3):109-11. [Medline].

  4. Ellenhorn MJ, Barceloux DG. Nitrates, nitrites, and methemoglobinemia. In: Medical Toxicology, Diagnosis and Treatment of Human Poisonings. 1988:844-851.

  5. Fitzsimons MG, Gaudette RR, Hurford WE. Critical rebound methemoglobinemia after methylene blue treatment: case report. Pharmacotherapy. Apr 2004;24(4):538-40. [Medline].

  6. Henretig FM, Gribetz B, Kearney T, Lacouture P, Lovejoy FH. Interpretation of color change in blood with varying degree of methemoglobinemia. J Toxicol Clin Toxicol. 1988;26(5-6):293-301. [Medline].

  7. Herman MI, Chyka PA, Butler AY, Rieger SE. Methylene blue by intraosseous infusion for methemoglobinemia. Ann Emerg Med. Jan 1999;33(1):111-3. [Medline].

  8. Howland MA. Methylene blue. In: Goldfrank's Toxicologic Emergencies. 8th ed. 2006:1746-1748.

  9. Price D. Methemoglobin inducers. In: Goldfrank's Toxicologic Emergencies. 8th ed. 2006:1734-1745.

  10. Umbreit J. Methemoglobin--it's not just blue: a concise review. Am J Hematol. Feb 2007;82(2):134-44. [Medline].

[ CLOSE WINDOW ]

Further Reading

[ CLOSE WINDOW ]

Keywords

methemoglobinemia, red blood cells, hemoglobin, methemoglobin levels, methemoglobin, hexose-monophosphate shunt pathway, diaphorase I, diaphorase II, heme group, iron, oxidation of iron, nicotinamide adenine dinucleotide, NADH, nicotinamide adenine dinucleotide phosphate, NADPH, methylene blue, cellular hypoxia, cyanosis, discoloration of skin, acidosis

[ CLOSE WINDOW ]

Contributor Information and Disclosures

Author

David C Lee, MD, Research Director, Department of Emergency Medicine, Associate Professor, North Shore University Hospital and New York University Medical School
David C Lee, MD is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, American College of Medical Toxicology, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Coauthor(s)

Kathy L Ferguson, DO, Attending Physician, Department of Emergency Medicine, New York Hospital of Queens, Queens, New York
Kathy L Ferguson, DO is a member of the following medical societies: American College of Emergency Physicians and American College of Medical Toxicology
Disclosure: Nothing to disclose.

Medical Editor

Lance W Kreplick, MD, MMM, FAAEM, FACEP, Medical Director of Hyperbaric Medicine, Fawcett Wound Management and Hyperbaric Medicine; Consulting Staff in Occupational Health and Rehabilitation, Company Care Occupational Health Services; President and Chief Executive Officer, QED Medical Solutions, LLC
Lance W Kreplick, MD, MMM, FAAEM, FACEP is a member of the following medical societies: American Academy of Emergency Medicine and American College of Physician Executives
Disclosure: Nothing to disclose.

Pharmacy Editor

John T VanDeVoort, PharmD, Regional Director of Pharmacy, Sacred Heart & St. Joseph's Hospitals
John T VanDeVoort, PharmD is a member of the following medical societies: American Society of Health-System Pharmacists
Disclosure: Nothing to disclose.

Managing Editor

Michael J Burns, MD, Instructor, Department of Emergency Medicine, Harvard University Medical School, Beth Israel Deaconess Medical Center
Michael J Burns, MD is a member of the following medical societies: American Academy of Clinical Toxicology, American College of Emergency Physicians, American College of Medical Toxicology, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Chief Editor

Asim Tarabar, MD, Assistant Professor, Department of Surgery, Section of Emergency Medicine, Yale University School of Medicine; Consulting Staff, Department of Emergency Medicine, Yale-New Haven Hospital
Disclosure: Nothing to disclose.

 
 
HONcode

We subscribe to the
HONcode principles of the
Health On the Net Foundation

All material on this website is protected by copyright, Copyright© 1994- by Medscape.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.