Pulse Oximetry

What does pulse oximetry measure?

The percentage of hemoglobin saturation (SpO2).

What is a normal SpO2 reading for a person breathing room air?

94% or greater.

What might an SpO2 reading below 94% in a nonsmoker indicate?

Hypoxemia.

When should oxygen be applied for a patient with a condition like a stroke or heart attack?

When the SpO2 drops below 94%.

Below what SpO2 reading do pulse oximeters become less reliable?

Below 85%.

How long can it take for a pulse oximeter to reflect a change in a patient's oxygenation status?

Up to 60 seconds.

What is a key principle for using a pulse oximeter in patient assessment?

To monitor the patient and supplement your assessment with the device's information, not rely on it alone

What should you do if a pulse oximeter cannot get a reading due to poor perfusion?

Move the sensor to a more central location like the bridge of the nose or the earlobe.

What are six factors that can cause an inaccurate pulse oximetry reading?

Hypovolemia, severe peripheral vasoconstriction, time delay in detection, dark or metallic nail polish, dirty fingers, and carbon monoxide poisoning.

Why can pulse oximetry give a normal reading in a patient with carbon monoxide poisoning?

Because it cannot distinguish between oxygen and carbon monoxide bound to hemoglobin.

If a patient shows signs of hypoxia but has a normal SpO2 reading, what should you do?

Treat the patient's condition, not the device

What is the first step in performing pulse oximetry?

Clean the patient's finger and place the index or middle finger into the probe, then turn on the device and note the SpO2 reading.

What should you do after noting the SpO2 reading on the pulse oximeter?

Palpate the radial pulse to ensure it correlates with the device's LED display.