If you have COPD, chances are good that you’ve had your index finger stuck into a small device called a pulse oximeter during a doctor’s office visit. Your doctor or staff use it to quickly check your oxygen levels. It’s essentially a measure of your lung health.
These devices have become available in the last decade for home use too. So the question is – do you need one? Let’s take a look at the pros and cons of using a pulse oximeter at home to help monitor your health status.
What is Pulse Oximetry?
Pulse oximetry uses a small device called a pulse oximeter to measure how much oxygen is in your blood. The device doesn’t use needles to access the bloodstream. Instead, it simply clamps on to a fingertip. A beam of light passes through the blood in your fingertip and measures the light-absorption in the hemoglobin in your blood. It is then able to calculate the amount of oxygen in the blood.
What it actually measures is something called your oxygen saturation level. This compares how much oxygen your blood is carrying to the total amount it could be carrying. The measurement is expressed in terms of a percentage. So, healthy people should have levels above 89%. But, more commonly they are at 95 to 100%.
People who have COPD can expect their levels to be lower. If you are on supplemental oxygen, however, the levels should still be in the 90s.
How Accurate Are Pulse Oximeters?
The good news is that pulse oximeters today are very accurate! In fact, tests have shown that generally the reading you will get from your oximeter will be within 2% of what an arterial blood gas (blood drawn from an artery) will show. So, for example, if the oximeter says your oxygen saturation level is 92%, it might actually be anywhere from 90% to 94%.
Keep in mind, though, that if you are having a severe COPD flare-up, and oxygen levels drop below 80%, the oximeter may no longer be as accurate. Other factors that can affect accuracy include:
- wearing nail polish or artificial nails
- having poor circulation
- cold hands from being outdoors
- holding the finger being measured above heart level
What Are the Benefits for Home Use?
Healthy people do not usually need a pulse oximeter. Nor do all people who have COPD. However, if you are using supplemental oxygen therapy at home, an oximeter can be a useful tool. Knowing your oxygen saturation levels can clue you in to when you need to use your oxygen and/or if it is working effectively.
Here are some times when a home pulse oximeter can be especially helpful:
- When you are just starting on oxygen, to help figure out the right level of oxygen for your needs
- During or after exercise; activity can increase your oxygen needs
- When flying in an airplane or traveling to high altitudes, as oxygen needs may increase
Please note that deciding what to do with a low oxygen saturation reading should always be done with your health care team. Oximeters are not designed for patients to manage their own treatment plan without consulting with a doctor.
So, Do You Need a Pulse Oximeter?
This is a decision that must be made with your doctor. Together, you can decide if this device would be useful, given your health status and your COPD treatment plan. If the answer is yes, your doctor may be able to write a prescription so that your health insurance will pay for the oximeter. If that is not possible, the price of these devices is quite low these days and you may even be able to purchase it online for a reasonable fee.
If you do add a pulse oximeter to your home treatment plan, then be sure you ask your doctor:
when he/she wants you to use the oximeter to monitor your blood oxygen level
- if and when you should change the flow rate on your supplemental oxygen
at what reading you should seek medical attention
And remember, that home pulse oximetry is not a substitute for medical care and management. It will also not replace arterial blood gas analysis, particularly in emergency situations. Nor will it replace your own personal assessment of how you are feeling. Always keep in touch with your health care team!