The perfusion index (PI) derived from a pulse oximeter is calculated as the ratio of the pulsatile blood flow to the non-pulsatile blood in peripheral tissue,11
Your healthcare provider may recommend you use a pulse oximeter (pulse ox). A pulse ox is a device that measures the percentage of oxygen in your blood. You may be given a percentage target for when you are at rest and another target for activity. Your provider may want you to keep a...