Carbon monoxide (CO) poisoning still represents a frequent and severe
casualty in France. Aside from the well-known effect of CO on hemoglob
in, the role of CO binding to other hemoproteins like myoglobin and cy
tochrome a3 has been more recently recognized. Moreover, in addition t
o these hypoxic injuries, the reoxygenation phase may itself induce to
xic effects by a mechanism close to the ischemia-reperfusion phenomeno
n. Clinical manifestations include neurologic disturbances, cardiac ar
rhythmia, respiratory and circulatory failures which usually disappear
with removal from toxic atmosphere and administration of oxygen. Howe
ver, long term neurologic manifestations may occur and lead to importa
nt functional impairment and disability. Hyperbaric oxygen is actually
the treatment of choice to avoid the occurrence of delayed sequelae.
HBO is advocated in every patient who remains comatose on hospital adm
ission, who has lost consciousness during toxic exposure or with persi
sting neurologic abnormalities. CO poisoned pregnant women should also
undergo HBO.