Want to watch this video? Sign up for the course here. Or enter your email below to watch one free video.

Unlock This Video Now for FREE

This video is normally available to paying customers.
You may unlock this video for FREE. Enter your email address for instant access AND to receive ongoing updates and special discounts related to this topic.

Now, we are going to have a closer look at pulse oximetry. Before we actually use pulse oximetry, we look at the patient themselves. What colour are they? Are they a nice pink colour? Are they blue? Are they cyanosed? Are they hypoxic? Are they using ancillary muscles to breathe? What is the actual condition and what signs are they showing us to say that they have an oxygen problem or a breathing problem? Are there any muscle damage? Are there any fractures? Or are there holes in the chest? We cover all that in another video. Now, we are going to actually have a look at the pulse oximetry itself and how we use it. First of all, it needs to go onto a finger. It can be used on an earlobe, and actually, some can be used on nasal cavities as well these days. But the finger itself, the nail itself, needs to be clean. Nail varnish can affect the way a pulse oximeter works. If we've got a tourniquet on an arm, that will affect the way a pulse oximeter works because we are cutting off blood supply. If we have a fracture on that arm that's affecting blood to the fingertips, that will also affect the reading that you get.

And also, things like tight clothing, posture, oxygen levels in the room that they're actually breathing, carbon monoxide, those sort of things will all give you potential false readings, or fake readings on a pulse oximeter. And we need to have an accurate reading. Non-accurate readings aren't worth taking at all. First of all, we find a finger. We make sure there is no restriction on the arm at all, not affecting the blood flow to that finger itself. One thing we can use very quickly to check that is cap refill. By squeezing the finger and allowing the capillaries to refill with blood. They should refill in under two seconds. If it's over two seconds, there is a restriction in blood flow which may affect the pulse oximeter. Also the colour of the finger. Is there any cyanosis to the fingertips, which is already showing this is an oxygen problem? Can we see those before we put the pulse oximeter on?

Pulse oximeters themselves. There are two types. There are the small finger probes, or the more complex ambulance type probes themselves. We will look at the finger for a start off. We turn it on. Once we have made sure that the finger is clean, there is no oils, grease, there is no nail varnish or anything else on the finger itself, it is clipped onto the finger. Now, we are looking for an oxygen saturation. These will give you an oxygen saturation and a pulse of the heartbeat. we are looking for an oxygen saturation between 98... 95, 98%. If that's the case, this patient does not require oxygen. They're breathing quite happily, their airways are working fine, oxygen is getting to the tips of the finger, and giving us an accurate reading. If it drops below 95, we are now talking about a hypoxic patient that does need some oxygen to help them breathe. Look at the condition, look at the way they're posturing, look at the way the pulse oximeter is reading, and make your decisions from accurate statistics and facts and figures. Don't guess. Don't jump to conclusions. These are designed to give us accurate feedback.

But as I said, don't forget, carbon monoxide in a room, tourniquets, even BP cuffs. We never put a pulse oximeter on the same arm where we are putting a BP cuff because as you blow the BP cuff up, you cut off blood supply. And with blood supply gone, you're not going to get an accurate reading whatsoever. We then get a reading onto the actual monitor itself, giving us an oxygen saturation between 95 and 98.