If you experience shortness of breath or have a pre-existing heart or lung condition, your healthcare provider may suggest using a pulse oximeter. But What Is An Oximeter, and how does it work? This device, also known as a Pulse Ox, is a non-invasive electronic device that measures the oxygen saturation level in your red blood cells.
How Does an Oximeter Work?
Oximeters are designed to be attached to various parts of the body, including fingers, forehead, nose, foot, ears, or toes. These devices can be reusable or disposable. If using an oximeter at home, consult with your healthcare provider before disposing of it, as these devices can be expensive and are typically reusable.
The pulse oximeter emits a cold light source that shines through the fingertip, causing the tip to appear red. By analyzing the light that passes through the finger, the device determines the percentage of oxygen in the red blood cells.
Factors Affecting Oximeter Accuracy
In February 2021, the Food and Drug Administration (FDA) issued an alert highlighting the limitations of pulse oximeters. Several factors can affect the accuracy of readings:
- Poor Circulation: Reduced blood flow to the extremities can lead to inaccurate readings.
- Skin Pigmentation: Dark skin pigmentation may affect light absorption and lead to inaccurate results.
- Skin Thickness: Thick skin can interfere with the device’s ability to accurately measure oxygen saturation.
- Tobacco Use: Current tobacco use can impact blood oxygen levels and oximeter readings.
- Skin Temperature: Cool skin temperatures can affect circulation and accuracy.
- Nail Polish/Artificial Nails: Dark fingernail polish or long, artificial nails can block the light source and interfere with readings.
- Cleanliness: Dirty fingers can also lead to inaccurate readings.
Because of these limitations, pulse oximeter readings should not be the sole determinant of your health status. It’s crucial to discuss abnormal or inconsistent readings with your healthcare provider.
What to Expect During Measurement
When used correctly, a pulse oximeter provides a simple, quick, and safe measurement of oxygen saturation levels. The probe is positioned on the selected body part, and within seconds, the oximeter displays your heart rate and oxygen saturation level. The procedure is painless and involves no needles. Some hospitals use disposable tape probes that wrap around the finger, nose, or toe.
Understanding Oximeter Results
The pulse oximeter offers a rapid measurement of oxygen saturation levels without the need for needles or blood samples. The reading on the screen reflects the percentage of red blood cells saturated with oxygen. This information helps doctors and nurses determine the appropriate treatment plan.
Oxygen saturation levels can also indicate whether supplemental oxygen is needed. A good oxygen saturation level typically falls above 90-92%. This value differs from the partial pressure of oxygen (pO2) measured from arterial blood (a good number is generally over 60-65). Your doctor can explain the significance of your specific value in relation to your individual health condition.
Risks Associated with Oximeters
When used and monitored by a qualified healthcare professional, pulse oximeters pose no known risks or dangers.
