Retired EMT here. Standard practice is to remove fingernail polish on the finger used for the pulse ox. Alternatively, you can put the probe on so it reads side

Retired EMT here. Standard practice is to remove fingernail polish on the finger used for the pulse ox. Alternatively, you can put the probe on so it reads sideways across the finger, though this isn't as reliable. Can attest that pulse ox is not as reliable for black people.