Seeking input from med folk - nurses - re SpO2 probes

dsm · Post by **dsm** » Fri Apr 14, 2006 4:42 pm

In another thread the topic of consistent readings from SpO2 probes came up.

Some of us questioned as to if it was normal or abnormal, to get different readings from different parts of the body.

I had commented that if I use a DS100A probe on my fingers I may get a reading of say 95% SpO2 sat.

But I also have a strap on probe and some DS25 disposable probes.

If I place a DS25 probe on my forehead I get a successful pulse reading plus tend to get a 99/100% SpO2 sat reading. I was really just playing around & not seriously expecting to get a good reading there but it is pretty consistent. If I manage to find a place on my hand for the DS25, the reading will be back to 95/96 so I consider this corrects the possibility that the DS100A I have (which was new) is giving different patterns of readings from the DS25s.

My questions to any professionals familiar with using these probes are ...

1) Can I expect to get a serious reading from my forehead or is it a distortion

2) Is it normal to get different readings from different parts of the body (seems reasonable to expect it)

Cheers

DSM

dsm · Post by **dsm** » Sat Apr 15, 2006 4:14 pm

No takers yet ?

Cheers

DSM

~AP · Post by **~AP** » Sat Apr 15, 2006 6:52 pm

There have been a few studies done to compare the efficacy of pulse oximeters. You can do a search on the internet to read the studies. Here is the conclusion of one done on volunteers who were deliberately desaturated to test the devices. (!)

"CONCLUSION: Most models of oximeters tested performed well when hemoglobin oxygen saturation was high, but all were inaccurate when SaO2 was approximately 75%. During induced hypoxemia, there were significant differences in the response times of oximeters tested, with no model demonstrably superior to others in all measures of performance."

I think we can safely say that not all oximeters are created equal and they are only tools for us to use to see shifts and trends. They are not infallible; they can break down, lose connection, and malfunction.

We use differnt ones at work, mostly they attach to a finger or toe. Babies get theirs taped on so they cann't kick it off, because if it isn't securely attached they will not read correctly. There are a lot of factors to consider - too numerous to list here. The forehead should be a good spot to have one attached because of the nearness of an important artery there.

In conclusion, as clinicians, what we look at is the patient, his/her coloring, level of conciousness, their vital signs, lab results, and how they are feeling otherwise. So - how are you feeling? Your answer will give us the best idea of how you are really doing.

dsm · Post by **dsm** » Sun Apr 16, 2006 12:11 am

~AP

Thanks,

What I was really interested in was the remark about the forehead being a viable place to take a reading. As said I keep geeting consistent readings there and also very high SpO2 % compared to fingers (I haven't actually tried a toe )

Thanks

DSM

~AP · Post by **~AP** » Sun Apr 16, 2006 11:42 pm

I would think that the forehead is a good place to check the O2 saturation, especially since you have noticed the consistency in your numbers. Sometimes the fingertips are not accurate simply because they are cold, or if fingernail polish is used.

Good luck - I think checking your O2 saturation is a good and worthy effort. I wish you good health.