Health care Fingertips Pulse Oximeter:Uses, Reading, Working

Device Description

A pulse oximeter is a device that is usually placed on a fingertip. It uses light beams to estimate the oxygen saturation of the blood and the pulse rate. Oxygen saturation gives information about the amount of oxygen carried in the blood. The pulse oximeter can estimate the amount of oxygen in the blood without having to draw a blood sample.

Most pulse oximeters show two or three numbers. The most important number, oxygen saturation level, is usually abbreviated SpO2, and is presented as a percentage. The pulse rate (similar to heart rate) is abbreviated PR, and sometimes there is a third number for strength of the signal. Oxygen saturation values are between 95% and 100% for most healthy individuals, but sometimes can be lower in people with lung problems. Oxygen saturation levels are also generally slightly lower for those living at higher altitudes.

What is the normal level?

As per the World Health Organization’s definition, an oxygen level between 95 – 100% is normal. Levels under 94% should be evaluated by a doctor, while levels below 90% are considered a clinical emergency and require immediate medical attention.

When you’re exposed to COVID-19, your lungs are one of the major organs to be affected. Damage to the lungs can cause the oxygen in your blood to drop to dangerously low levels, even when you feel generally well, or present no other symptoms of the virus. This is known as “silent pneumonia” and if left untreated, can lead to very serious consequences.

How to take a reading:

1. Follow the manufacturer’s instructions for use.

2. When placing the oximeter on your finger, make sure your hand is warm, relaxed, and held below the level of the heart. Remove any fingernail polish on that finger

3. Sit still and do not move the part of your body where the pulse oximeter is located.

4. Wait a few seconds until the reading stops changing and displays one steady number.

Recommendations for Health Care Providers

1. Be aware that multiple factors can affect the accuracy of a pulse oximeter reading, such as poor circulation, skin pigmentation, skin thickness, skin temperature, current tobacco use, and use of fingernail polish. Review the information in the sections below to better understand how accuracy is calculated and interpreted.

2. Refer to the device labeling or the manufacturer’s website to understand the accuracy of a particular brand of pulse oximeter and sensor. Different brands of pulse oximeters and even different sensors (finger clip versus adhesive) may have a different accuracy level. Pulse oximeters are least accurate when oxygen saturations are less than 80%.

3. Consider accuracy limitations when using the pulse oximeter to assist in diagnosis and treatment decisions.

  1) Use pulse oximeter readings as an estimate of blood oxygen saturation. For example, a pulse oximeter saturation of 90% may represent an arterial blood saturation of 86-94%.

  2) When possible, make diagnosis and treatment decisions based on trends in pulse oximeter readings over time, rather than absolute thresholds.