What does an SpO2 reading indicate on a pulse oximeter?

A pulse oximeter measures the saturation of peripheral oxygen, commonly referred to as SpO2. This reading represents the percentage of hemoglobin in the blood that is saturated with oxygen, which indicates how well oxygen is being transported throughout the body.

A normal SpO2 reading typically ranges from 95% to 100%, showing that the body is receiving sufficient oxygen to meet its needs. If the reading is significantly lower than this range, it can signal a potential problem with oxygenation, necessitating immediate assessment and possibly intervention.

While it may be tempting to think of other physiological parameters like heart rate or gas exchange rates in relation to pulse oximetry, those are not directly measured by the device. Heart rate is monitored through a separate function or device, and carbon dioxide levels are assessed using different monitoring methods, such as capnography. Hence, the focus on SpO2 provides valuable insight specifically into oxygen saturation, distinguishing it from other blood gas parameters.