Pulse Oximeter and CPAP Therapy

Pulse Oximeter and CPAP Therapy

August 23, 2013 | |

What is a Pulse Oximeter?

Firstly, let’s describe a pulse oximeter and how it functions.  A pulse oximeter, most often worn on the fingertip, is a medical device that measures oxygen saturation levels in a person’s blood.  In other words, it measures the amount of oxygen present in the bloodstream.  It is typically for people who have the potential for unstable blood oxygen levels like those that are already in intensive care units and emergency rooms.  The finger pulse oximeter uses a red and infrared light to measure the oxygenation in the fingertips.

How is this possible? Because Hemoglobin (the part of the blood that transports oxygen) absorbs different amounts of light depending upon how much oxygen it is transporting.  Although this is an indirect method of measuring oxygen levels, it has proven to be reliable.  In fact, a good pulse oximeter is sensitive enough that it will ignore any signals sent by tissue in the fingertip and will not be distracted by substances such as nail polish. Only the light absorption of hemoglobin is measured.

Why is Blood Oxygen Level Important?

Low blood oxygen levels are harmful for many reasons.  But let us consider how blood oxygen relates to sleep apnea and CPAP therapy.  Low oxygen levels certainly may indicate a serious health problem.  People with sleep apnea or an underlying lung disease such as asthma or COPD, sometimes have blood oxygen that drops to unhealthy or even fatal levels.  When people suffer from sleep apnea, their airways close and oxygen does not flow to the brain and bloodstream.  Oxygen levels then fall, triggering the brain to arouse the body.  Although this happens subconsciously, the body continually awakens negating the positive benefits of a deep and restful sleep.  This vicious cycle is the typical symptom of sleep apnea.  A pulse oximeter can read oxygen levels to help to confirm a diagnosis of sleep apnea.

Using a Pulse Oximeter with CPAP

Once you have been diagnosed with sleep apnea and are using your CPAP machine, it is important to confirm you are receiving the full benefits of the therapy.  Of course, the reason behind using a CPAP machine is to maintain the integrity of your airways in order to breathe normally and deliver oxygen to the bloodstream.  Oxygen saturation over 94% is typically considered normal. Anything below 92% is a signal that you are not receiving the full benefits from your CPAP therapy. 

A pulse oximeter can supplement any software available with your CPAP machine by measuring this important gauge of the effectiveness of your treatment.  Simply attach the pulse oximeter to your fingertip and let it record your levels.  There are, of course, nuances that need to be users need to understand when reading the results such as how much time you spend at certain low levels.  But overall, it will give you a barometer for keeping CPAP therapy as is or speaking to your doctor about optimizing.

Types of Pulse Oximeters

Finger pulse oximeters are the most popular type of oximeters because they are affordable, lightweight and easy to use.  Many finger pulse oximeters even measure the user’s heart rate in addition to their oxygen saturation. There are also more sophisticated devices with Bluetooth and optional wireless transmitter and receiver links.  Although most people will only require a simple pulse oximeter if you are reading just oxygenation levels, a more complex version might be worthwhile when more information or supplemental oxygen is necessary.

For additional information on various topics concerning sleep apnea and CPAP products, please refer to our blog.  It has constant updates and offers free advice and information.  If you’d like to learn more about the quality sleep apnea products we carry, or if you have additional questions, don’t hesitate to contact us through our website or you can call us at (866) 414-9700.

Chris Vasta

Chris Vasta is the president of The CPAP Shop and an expert in sleep and respiratory therapy. He often provides insights on product design and functionality on various manufacturers’ prototypes and is frequently tapped to provide reviews on new releases.