Pulse Oximetry

What is a Pulse Oximeter?

A device used to measure the SpO2 oxygen level (or oxygen saturation) in the blood. It is considered to be a noninvasive, painless, and a general indicator of oxygen delivery to the peripheral tissues (such as the finger).

Who should use a Pulse Oximeter?

Anyone that needs to monitor their oxygen levels on a regular basis. People using concentrated oxygen, or those with chronic illnesses of the respiratory or cardiac system benefit the most from knowing how well oxygenated they are. Oximeters are mostly used by athletes, climbers, pilots and divers to guarantee they are properly oxygenated.

How does a Pulse Oximeter work?

The oximeters have 2 light-emitting diodes (LEDs) that shine through your fingertip. One LED is red and the other is Infrared. The photodiode on the opposite side of the LEDs measures how much light is able to pass through or be absorbed to determine an accurate measurement. SInce your blood circulates in periodic pulses, the oximeter will also measure your heart rate, and use that to further the accuracy of the measurement.

What are the different types of Pulse Oximeters?

Fingertip: Most common type used at home and outside of the clinic. They provide oximetry and pulse reading on the top of the area that clips onto the finger. 

Handheld: Usually more sophisticated than a fingertip oximeter and are most commonly recommended for use at a clinic. They feature a fingertip sensor that is attached to a handheld display device.

Wrist: Also provide a reliable reading for individual users, but use a display that attaches like a watch to a user’s wrist. They can make readouts and regular usage much easier for patients who do not wish to constantly carry around a fingertip oximeter.

Tabletop: Used frequently in labs and hospitals to monitor patients and conduct sleep studies. These also utilize fingertip probes that are attached to a hardware device which provides useful information to medical professionals. These are much bigger than other pulse oximeters.

What is considered to be a normal oxygen level?

Although everyone's oxygen levels will vary, it is good practice to gauge your levels by testing yourself at least 4 times a day for a period of 1 week and record the measurements. This will give you a fairly good range of your average oxygen  levels. 

• An SpO2 of greater than 95% is generally considered to be normal.
• An SpO2 of 92% or less (at sea level) suggests Hypoxemia.

What is Hypoxemia and Hypoxia?

Hypoxia is a condition in which the entire body, or a specific region of the body (tissue, organs) is either deprived or not receiving an adequate supply of oxygen.

Hypoxemia is also a low level of oxygen in the blood, but more specifically in arterial blood.

Last updated on May 13, 2015