Carbon monoxide
Intoxication – Review
Cetin
KAYMAK*°, Hulya BASAR**
* MD, PhD, Associate Professor, Ministry of Health, Ankara
Education and Research Hospital, Department of
Anesthesiology and Reanimation, Ankara, Turkey
** MD, Associate Professor, Ministry of Health, Ankara
Education and Research Hospital, Department of
Anesthesiology and Reanimation, Ankara, Turkey
° Corresponding Author E-mail: cetinkaymak@yahoo.com
Summary
Carbon monoxide (CO), is a toxic gas produced by incomplete
combustion of carbon containing materials such as kerosene,
gasoline, propane and coal. As it’s a colourless, odorless,
tasteless and non-irritating gas, CO is described as
the“silent killer”.
CO, binds to the iron atoms in hemoglobin, with an affinity
200-250 times that of oxygen, and impairs oxygen carrying
capacity of the blood. Hence, CO toxicity is a situation
characterized by impairment of oxygen transportation and
consumption. It has been reported that 30% of such cases are
not diagnosed since the signs and symptoms in CO
intoxication. Definitive diagnosis of CO intoxication is
established by measuring the COHb concentration in arterial
or venous blood. Elimination half life of COHb and partial
oxygen pressure produced by inspired oxygen concentration is
closely related. High levels of inspired oxygen fractions
both accelerate CO removal and improve oxygenation.
Hyperbaric oxygen (HBO) treatment is first discussed in
1890’s and was initially used in 1960’s. Although,
acceleration of removal of the CO from hemoglobin was aimed
initially, other effects were recognized in time. When HBO
treatment is not possible, high flow 100% oxygen is applied
via tight-fitting face mask. for 6-12 hours. Although, the
dominance of f HBO to normobaric oxygen theraphy has been
supported by several studies, more randomized clinical
trials are needed.
In general, most of the CO intoxications are nonfatal. Cases
with mild symptoms and those that do not show any
neurological symptoms can be discharged from hospital after
4-6 hours of treatment. Despite the therapy, it is still
impossible to predict long term results of CO intoxication.
Key Words :
Carbon monoxide, Intoxication