4.6: Oxygen Saturation

Oxygen saturation

Measures the fraction of hemoglobin saturated with oxygen bound to iron, relative to total body hemoglobin

Arterial blood

Blood with highly saturated hemoglobin, usually 97% to 100%

Venous blood

Blood with lowest oxygen-saturated hemoglobin, usually 60% to 80%

Externally attached pulse oximeter

Only measures arterial oxygen saturation

Newborn and infant pulse oximeter placement

On the foot

Adult pulse oximeter placement

On a finger

Step 1 to measure oxygen saturation

Step 2 to measure oxygen saturation

If there is any nail polish, remove it

Step 4 to measure oxygen saturation

Check the closest arterial pulse in the chosen extremity and make sure it is not too cold

Why should you not use any extremity that is too cold?

The blood vessels will be constricted, distorting the actual oxygen level

Step 4 to measure oxygen saturation

Wipe the finger or foot with an alcohol pad

Step 5 to measure oxygen saturation

Attach the sensor to the finger or foot

Step 6 to measure oxygen saturation

Read and document the measure oxygen saturation level