What is human respiratory system?

Hypotension can alter the pulse oximeter values in a client suffering from respiratory arrest.
A pulse oximeter is a medical device that is used to monitor oxygen saturation of a client's blood non invasively. Blood volume deficiencies like conditions that cause hypovolemia, hypotension and hypothermia are known to alter the value of a pulse oximeter.

This is mainly because these conditions may cause a reduction in the blood flow even if the client has adequate oxygen saturation. The sensor may not be able to detect the pulsatile waveform which results in the alter values seen on the pulse oximeter. Fever, tachypnea and tachycardia do not directly alter the readings on pulse oximeter.