Pulse Oximetry and DCS

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sharkbaitDAN

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Does anyone know if pulse oximetry works with a person who has DCS? Do the N2 bubbles interfere with the reading? Patients should be getting O2 anyway, just wondering if anyone knows.
 
Pulse oximetry measures the 02 saturation levels of RBCs. I see no reason that DCS would interfere with the use of PO.
 
sharkbaitDAN:
Does anyone know if pulse oximetry works with a person who has DCS? Do the N2 bubbles interfere with the reading? Patients should be getting O2 anyway, just wondering if anyone knows.


Pulse oxymetry is actually very simplistic technology. It measures the amount of "redness" that is created when oxygen attaches itself to the hemoglobin on red blood cells. The devices do not actually measure the oxygen but the color that the hemoglobin produces at varying degrees of oxygen saturation. You can easily fool a pulse oxymeter with a patient or diver with CO poisoning because the hemoglobin actually has more of an affinity for Carbon Monoxide than it does for oxygen, 1700 times more. So pulse oxymetry can actually be called a colormetric meter more than a gas specific meter, because it doesn't actually measure the gas but the color.
 
There is no reason that N2 bubbles should interfere with pulse oximetry readings.

In the absence of specific abnormalities, bubbles are not expected in arterial blood, are not present for very long even in the rare circumstance when they are and in any event wouldn't measurably affect pulse oximetry.

Best regards.

DocVikingo
 

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