COHb

carboxyhemoglobin

Haemoglobin (Hb) with irreversibly bound carbon monoxide (COHb). COHb levels reflect CO exposure, which increases in fires and with exposure to car exhaust; Some COHb occurs naturally as a product of Hb catabolism and due to increased turnover of Hb in newborns, coupled with reduced efficiency of the infant’s respiratory system, leading to increased COHb.

Carboxyhaemoglobin levels
• < 2%: Non-smokers;
• 2%–12%: Smokers;
• > 20%: Toxic;
• > 50%: Lethal.

Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

Carboxyhemoglobin (COHb)

Hemoglobin that is bound to carbon monoxide instead of oxygen.

Mentioned in: Carbon Monoxide Poisoning

Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.