In patients with oxygen saturation at or above 90 percent, peripheral pulse oximeters (devices widely used to measure oxygen saturation) have similar readings regardless of whether they are approved for medical use. This is according to a recent study of oxygen saturation in patients using one pulse oximeter approved for medical use by the US Food and Drug Administration compared to eight devices labeled "Not for Medical Use" and not FDA reviewed. Non-approved pulse oximeters are commonly sold in drugstores and over the Internet. Nineteen women and 41 men were studied and 669 data points (69-104 per oximeter) were obtained. There was no meaningful difference in displayed oxygen saturations between medical use and non-medical use pulse oximeters in the range from 90-99 percent. Non-medical use pulse oximeters, the authors suggest, may therefore be able to rule out hypoxemia, an abnormally low concentration of oxygen in the blood, in clinical settings. Because pulse oximeter measurements of oxygen saturation are less accurate below 90 percent, however, patient management decisions regarding oxygenation should be verified using a device intended for medical use whenever possible.
Clinical Interpretation of Peripheral Pulse Oximeters Labeled "Not for Medical Use"
Arlene J Hudson, MD, MA, et al
Uniformed Services University of the Health Sciences, Bethesda, Maryland