Limitations

Pulse oximeters rarely cause any harm directly, though apparently some older models could cause burns and there are reports of the probes causing pressure ulcers. However if their limitations are not borne in mind harm could be caused by someone having the wrong (or no) treatment. So it's important to know what the limitations are.

One limitation is that pulse oximeters cannot operate reliably with a poor signal. This has been refered to as a 'safe' limitation, in that the pulse oximeter is not able to give an accurate reading but in some way indicates this fact. Obviously pulse oximeters need to be technically capable of indicating this and the person using it must be aware of this point.

The other sort of limitation is more dangerous in that the pulse oximeter may appear to have a good signal and be displaying a saturation figure, but either the figure is inaccurate or gives a false sense of security.