Methaemoglobin

Jump to: navigation, search

WikiDoc Resources for Methaemoglobin

Articles

Most recent articles on Methaemoglobin

Most cited articles on Methaemoglobin

Review articles on Methaemoglobin

Articles on Methaemoglobin in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Methaemoglobin

Images of Methaemoglobin

Photos of Methaemoglobin

Podcasts & MP3s on Methaemoglobin

Videos on Methaemoglobin

Evidence Based Medicine

Cochrane Collaboration on Methaemoglobin

Bandolier on Methaemoglobin

TRIP on Methaemoglobin

Clinical Trials

Ongoing Trials on Methaemoglobin at Clinical Trials.gov

Trial results on Methaemoglobin

Clinical Trials on Methaemoglobin at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Methaemoglobin

NICE Guidance on Methaemoglobin

NHS PRODIGY Guidance

FDA on Methaemoglobin

CDC on Methaemoglobin

Books

Books on Methaemoglobin

News

Methaemoglobin in the news

Be alerted to news on Methaemoglobin

News trends on Methaemoglobin

Commentary

Blogs on Methaemoglobin

Definitions

Definitions of Methaemoglobin

Patient Resources / Community

Patient resources on Methaemoglobin

Discussion groups on Methaemoglobin

Patient Handouts on Methaemoglobin

Directions to Hospitals Treating Methaemoglobin

Risk calculators and risk factors for Methaemoglobin

Healthcare Provider Resources

Symptoms of Methaemoglobin

Causes & Risk Factors for Methaemoglobin

Diagnostic studies for Methaemoglobin

Treatment of Methaemoglobin

Continuing Medical Education (CME)

CME Programs on Methaemoglobin

International

Methaemoglobin en Espanol

Methaemoglobin en Francais

Business

Methaemoglobin in the Marketplace

Patents on Methaemoglobin

Experimental / Informatics

List of terms related to Methaemoglobin


Overview

Methemoglobin (pronounced MET-hemoglobin) is a form of the oxygen-carrying protein hemoglobin (British English: haemoglobin), in which the iron in the heme group is in the Fe3+ state, not the Fe2+ of normal hemoglobin. Methemoglobin is unable to carry oxygen. It is chocolate-brown in color. The NADH-dependent enzyme methemoglobin reductase (AKA diaphorase I) is responsible for converting methemoglobin back to hemoglobin.

Normally one to two percent of people's hemoglobin is methemoglobin; a higher percentage than this can be genetic or caused by exposure to various chemicals and depending on the level can cause health problems known as Methemoglobinemia. A higher level of methemoglobin will tend to cause a pulse oximeter to read closer to 85% regardless of the true level of oxygen saturation.

Common causes

  • Reduced cellular defense mechanisms
    • Children younger than 4 months exposed to various environmental agents
    • Methemoglobin reductase deficiency
    • G6PD deficiency
    • Hemoglobin M disease
    • Pyruvate kinase deficiency
  • Various pharmaceutical compounds
    • Local anaesthetic agents, especially prilocaine as used in the Bier block
    • Amyl nitrite, chloroquine, dapsone, nitrates, nitrites, nitroglycerin, nitroprusside, phenacetin, phenazopyridine, primaquine, quinones and sulfonamides
  • Environmental agents
    • Aromatic amines
    • Arsine
    • Chlorobenzene
    • Chromates
    • Nitrates/nitrites

Methemoglobinemia in infants

In children, this condition is known as blue baby syndrome, attributed primarily to excessive nitrate intake from drinking well water.

External links

cs:Methemoglobin da:Mæthæmoglobin de:Methämoglobin it:Metaemoglobina



Linked-in.jpg