Although COHb does not make you 'cherry pink' to the naked eye, the absorption spectrum of COHb does cause problems with pulse oximetry.
A simple pulse oximeter simply measures how 'pink' the patient's blood is. "If a patient looks pink to you, they look pink to an oximeter." Pulse oximeters are confused by COHb, and read it as oxy-Hb. So someone with, say, 30, 40 50% COHb on board will have a PulsOx reading ticking along quite happily at 98%!
So not only is simple oximetry useless for detecting CO exposure, it is actually misleading in, for example, someone from a house fire.
The important exception to this are pulse oximeters like the Rad 57, which is designed specifically to test for COHb.
A simple pulse oximeter simply measures how 'pink' the patient's blood is. "If a patient looks pink to you, they look pink to an oximeter." Pulse oximeters are confused by COHb, and read it as oxy-Hb. So someone with, say, 30, 40 50% COHb on board will have a PulsOx reading ticking along quite happily at 98%!
So not only is simple oximetry useless for detecting CO exposure, it is actually misleading in, for example, someone from a house fire.
The important exception to this are pulse oximeters like the Rad 57, which is designed specifically to test for COHb.
No comments:
Post a Comment