Pulse ox reading poorly

NOADLS · Sep 13, 2015

Check on a different person. I personally check it on myself if I doubt the reading.

You can also use different assessment pieces to help you make a decision with the information you have (ie. CWMS). What are the person's respirations like?

If in absolute doubt, you can also call an ambulance and have the patient transferred. You'll also be able to see if there was a difference in pulse oximetry between your reader and the one the EMT uses.

**NICU Guy, BSN, RN** · Sep 13, 2015

The reading may be erroneous because of poor circulation in that finger/ hand. Try a different finger or hand. If possible try the ear lobe

Karou · Sep 13, 2015

How often are the pulse ox censers calibrated? They should be on a regular basis to ensure they are working correctly.

Some people are difficult to get accurate readings on because their hands are cold, fingers bent, or their capillaries are small. You can try different fingers if you suspect a false low reading, or try to warm their hand by placing it under a blanket. Comparing the reading to another pulse box machine can help verify the reading is accurate.

It's not uncommon to get a reading on the 80's though. Especially for chronic COPD patients. With those patients, it may even be their normal to stay in the high 80's. The most important thing to do is look at the patient when you get a funky reading.

People can also appear to be in no obvious respiratory distress, but actually not be oxygenating well. It could be from anemia/blood loss or a respiratory problem that they aren't diagnosed with and have subtle symptoms of. They can also have a fine pulse ox reading but actually be in respiratory distress.

Had a nurse tell me my patient was fine during hand off "because he is 96% on room air", but the guy was wheezing/crackling, tachypenic, with accessory muscle use and obvious labored breathing. He was NOT fine.

My point is that a pulse ox reading is a good assessment tool but not the only one, or the most important. Look at the whole picture of what's going on with your patient. 89% may be normal for your chronic COPD patient and your 95% on room air guy may have CHF and be drowning in his own fluids.

tsm007 · Sep 13, 2015

How often are the pulse ox censers calibrated? They should be on a regular basis to ensure they are working correctly.
Some people are difficult to get accurate readings on because their hands are cold, fingers bent, or their capillaries are small. You can try different fingers if you suspect a false low reading, or try to warm their hand by placing it under a blanket. Comparing the reading to another pulse box machine can help verify the reading is accurate.
It's not uncommon to get a reading on the 80's though. Especially for chronic COPD patients. With those patients, it may even be their normal to stay in the high 80's. The most important thing to do is look at the patient when you get a funky reading.
People can also appear to be in no obvious respiratory distress, but actually not be oxygenating well. It could be from anemia/blood loss or a respiratory problem that they aren't diagnosed with and have subtle symptoms of. They can also have a fine pulse ox reading but actually be in respiratory distress.
Had a nurse tell me my patient was fine during hand off "because he is 96% on room air", but the guy was wheezing/crackling, tachypenic, with accessory muscle use and obvious labored breathing. He was NOT fine.
My point is that a pulse ox reading is a good assessment tool but not the only one, or the most important. Look at the whole picture of what's going on with your patient. 89% may be normal for your chronic COPD patient and your 95% on room air guy may have CHF and be drowning in his own fluids.

Thank you. That was helpful. You can't calibrate these. They are just the personal pulse ox's like they use at doctors' offices or that you can buy on Amazon for personal use. However, I did try warming up the patient's hands. I ran some warm water and warmed a washcloth. I don't know why I just thought maybe that was the problem and it did seem to read more accurately then. I just wondered if cold hands would cause a poor reading OR then my other thought was that maybe poor oxygenation would cause cold hands.

I do realize you need to look at the whole picture. This particular patient's baseline was not in the 80s. He did not appear in respiratory distress. My question was more looking for tips to get the oximeter to read so I could have that information to include in my assessment.

tsm007 · Sep 13, 2015

The reading may be erroneous because of poor circulation in that finger/ hand. Try a different finger or hand. If possible try the ear lobe

Going to experiment and see if you can actually get this kind of oximeter to read on the ear lobes. If that works I will start using that.

icuRNmaggie, BSN, RN · Sep 13, 2015

Cold hands, weak pulses, drop in urine output, loss of the Sp02 reading, and a subtle change in mentation are ominous signs of poor perfusion and impending shock. Check the feet and legs for mottling as well.

The loss of the 02 sat is often the first thing that is noticed by the staff and it really is cause for concern.

tsm007 · Sep 13, 2015

Cold hands, weak pulses, drop in urine output, loss of the Sp02 reading, and a subtle change in mentation are ominous signs of poor perfusion and impending shock. Check the feet and legs for mottling as well.
The loss of the 02 sat is often the first thing that is noticed by the staff and it really is cause for concern.

When I rechecked this pt after warming his hands his O2 was 94% and later in the shift to recheck it was 98% first try. This is why I am asking questions because I want to know this. We had a temp drop this weekend and a lot of my residents were cold today. He was oriented and having appropriate conversation with me. His overall color was good. His breathing was unlabored. I have seen him have respiratory distress before so he didn't look in distress at this moment. Which is why I rechecked his pulse ox because his presentation did not match the number on the machine. I just noticed that I sometimes have problems getting these handheld oximeters to read. They can sit there forever to pick up a number on some of my residents, but then I put it on my own hand and it reads in seconds. I knew I had read tips for the pulse ox's in the hospital like blocking light, making sure they didn't have nail polish on (which many of my residents do have bright red nail polish), etc. So I was hoping there were tips for the handhelds as well because that is all I have access to.

icuRNmaggie, BSN, RN · Sep 13, 2015

Clean the led sensors with dry gauze. A lot of finger grease can build up in there.

If there is a cord, it can fracture just like your iphone

charger so it may need to be replaced.

Rub the finger to warm it up and place it at the level of the heart.

Sometimes we try the second toe and even place the sensor sideways on the finger and that just seems to be the best site for some people.

tsm007 · Sep 14, 2015

I found a great post on this on a firefighter/EMT forum since they use portable pulse oxs! They suggested turning the finger sideways if the patient has nail polish and they also said if they were cold from environmental temps it could effect the reading so you can warm them up. Sorry, just feeling accomplished in the fact that I put together the fact that his cold hands were what were messing up today's readings. We had a big temp drop this weekend and it was cold in the building. I wore a jacket all day which I normally do not. It was just weird that I was having problems with so many residents taking a long time to read on the pulse ox or giving erroneous numbers (one was reading at 71).

Nonyvole, BSN, RN · Sep 14, 2015

Think about what happens when the body is in a cold environment. Blood flow decreases to the extremities, which is why fingers are terrible places for an accurate pulse-ox reading in somebody with cold hands.

Really, anything that decreases blood flow into the fingers will affect readings.

As will CO poisoning, because the CO binds to the hemoglobin instead of the O2. And the pulse-ox is reading just the percentage of RBCs that have something bound to them, so with patients who have carbon monoxide poisoning, readings can be artificially elevated.

Good job troubleshooting, though. You figured out what the problem was. :)

Angelicamarie · Sep 14, 2015

Pulse ox can be sensitive to things like sunlight and temperature. I had a patient on continuous pulse ox desat down to the 60s while holding a cup of ice water. She was alert and engaging in conversation. As soon as she put down the cup and her hand warmed back up her sats went normal again.