Pulse Oximeter Basics

There's a lot of info out there about pulse oximeters, and not a lot of time to sort through it all. Some people only want to know a few key facts rather than the whole encyclopedia article. The following is a summary of the basics of a (Devon) fingertip pulse ox (and probably others):

How to Use:

When you get your pulse ox, open the box and insert batteries (provided). Make sure they match the picture.

Place the pulse ox on your finger. The Red LED light should be facing the TOP of your finger (into the pink fingernail part).

Most units will start automatically if you put them on, some require you to press the button.

Pressing the button on some units (C202, PC60C, C3, PC60E, etc) will rotate the display.

Most readings will appear and stabilize within 5-10 seconds. Most fingernail polish won't affect readings, but too much movement, light (in the LED area), or bad circulation could lower the reading.

Why it Works:

The pulse oximeter actually has two LEDs; a red one, and an infrared one. Both are different wavelengths and are aimed at a translucent part of a person's body (in this case, the fingertip).

Each LED is a different wavelength, and each one acts significantly different when it comes to blood cells with oxygen and blood cells without oxygen.

The pulse oximeter can take the ratio of the two LEDs being absorbed/reflected, and tell how much of the blood is oxygenated or not.

There's much more to be said about how these work, but I'm trying to keep it relatively simple here (hopefully it didn't come off as too technical!). For more information just search for pulse oximeter on Google and I'm sure someone can give you the detailed facts. www.devonsuperstore.com should soon have instruction manuals available online (they're already included with each purchase) so you can read all about each individual unit before/after purchase. As always, I will answer any questions/comments here, and thanks for reading!