When to believe the pulse oxymeter, when not?

[Bernhard]

As providers we need to rely loess on our toys, and rely more on our training, education, and instincts. The old mantra says "treat the patient, not the equipment" and I believe that 100%.

That wasn't quite the problem. The problem was, that my initial assessment (case#1) didn't meet the pulse ox reading BY FAR. Plus an other pulse oxymeter gave a more probable reading instantly on the same finger.

• Inital assessment: pretty OK, no problem breathing, no sign of O2-need
  
• pulse oxymeter #1 (technically OK): 60%
  
• pulse oxymeter #2 (technically OK): 95%
  

The total and large variation of values made me wonder. I didn't hesitate to put the 60% away as crap value, so no harm done. But I wondered what a pulse oxy will give me when I have to rely on a 1% delta (is it 98% or 99%?) and what sense it really makes when we have this small range in mind or in the guidelines for deciding between yes and no.

We as a profession need to put EMPHASIS on our assessments, and use our technology as a backup, and not the other way around.

That may lead to a wrong understanding of tools. There are conditions you can't detect without tools. I prefer to know my tools and to use them in an appropriate way. Sure, I'm able to help with bare hands and naked, but that isn't what I want to do when arriving with an ambulance (OK, my employer would be happy when I would do the job without any tools...not naked, though).

[tniuqs]

(is it 98% or 99%?)

Ok so what altitude asl are you located at ?

[Aussieaid]

I agree with you. Incorrect reading tend to be low (affected mostly by issues in the finger - cold hands, poor circulation, etc.). Sometimes, moving the sensor to an earlobe or a toe helps. I have seen patients compensating extremely well for chronically low PO2 (long term COPDrs for example) where low SPO2 readings are correct and have had these readings dismissed by providers.

A low SPO2 reading is one of my indicators to absolutely put the patient on end tidal canula. If corresponding ETCO2 is low, then it is a strong impetus to give em some Os. Conversly, high ETCO2 with low SPO2 becomes a balancing act.

Like every other device that assists in evaluation, the SPO2 reading is just one piece of the bigger picture.

Do you mind explaining the rational regarding your statement, "A low SPO2 reading is one of my indicators to absolutely put the patient on end tidal canula. If corresponding ETCO2 is low, then it is a strong impetus to give em some Os. Conversly, high ETCO2 with low SPO2 becomes a balancing act."?

[Bernhard]

Ok so what altitude asl are you located at ?

Usually between 500 and 700 meter over german normal zero. However, I don't know at which altitude the German Resuscitation Council was when giving out this 94%-98% range in their guidelines.

BTW: I still have to read the original english text of the guidelines. I meanwhile don't rely on the translation here either. EMTcity makes you (general "you") very suspicious...

[Just Plain Ruff]

Come on, aren't we all slaves to the machines? I mean when you get out of EMT school you are like a sheep and you follow what your machine tells you right? Machine tells you low pulse ox, slap em on oxygen.

Machine tells you it looks like v-fib or asystole you go ahead and get ready to code em, even before you check a pulse

Your d-stick machine says "low" but the patient is talking to you. so drop an amp of D-50 down the iv tubing.

I mean we all are slaves to the machines and we might as well be assimilated NOW instead of later.

[Kaisu]

Do you mind explaining the rational regarding your statement, "A low SPO2 reading is one of my indicators to absolutely put the patient on end tidal canula. If corresponding ETCO2 is low, then it is a strong impetus to give em some Os. Conversly, high ETCO2 with low SPO2 becomes a balancing act."?

Glad you asked. I really didn't explain myself very well did ? If I have a low SPO2 reading, one of the other things I want to know is what is the end tidal CO2. The device I have to determine this (besides an inline detector) is the nasal canula that detects exhaled CO2. I would put this on the patient to monitor ETCO2. I would not necessarily administer O2. In this situation, I am using the canula as an ET detector only.

Hope this clears things up.

Oh wait.. just read more of your post..

Are you asking about the respiratory physiology? specifically the inability of some patients to "blow off" carbon dioxide?

[DwayneEMTP]

Squint, though I didn't understand much of your post, (Though I did relish the descriptions of you being old, fat and blind), I think perhaps you come from a different place in your ideas of the machines than many of us, certainly different than me.

Your education regarding the machines, experience with them in and out of hospital, as well as knowledge and experience regarding the information delivered by them when compared to pt presentation is vast compared to mine. I believe that allows you a lot of confidence in them that I don't have.

Though I'm relatively young in EMS, and in spirit, it's possible some of my attitudes are slightly older. I think the tone of the conversation here isn't against machines, but against the inability of many providers to manage patients without using them.

I think in prehospital EMS, and again, certainly in my mind, there is always the attitude of 'worst case.' What if you don't have them, what if they don't work, what if they don't make sense compared to what your assessment has shown? And I think that that is a healthy, particularly in the remote setting where you're more often in a position to say, "Why does that guy seem so pale and sweaty? His gait seems kinda unsteady...I'd better snatch him up and take a look." I'm not aware of any machines that are going to do that.

Would I expect an RT to develop an ongoing treatment plan without the use of machines? Of course not. Would I expect you to be unable to develop an immediate, 'circling the drain' plan for a patient that had just been brought into the ER without them? Yeah..very much so.

We sometimes argue these points as if a call, is a call, is a call, kind of like we do when we discuss disciplining children. But that's of course not the case.

If I come to the old folks home to find an 80 year old woman with slightly altered consciousness, somewhat cyanotic, RR 26/adequate depth, P 120, am I going to want an SPO2 and ECG? Of course.

If I arrive to find the same patient tripoding, RR 36, P 130, appearing to be wearing her favorite pale blue lipstick, exhausted and looking like she's about to tip over from exhaustion, is the pulse ox going to be the first thing out of my bag? No...it's going to fall a far bit behind in priorities to my stethoscope, but I do believe that it will be the first thing out of many providers bags.

But again, perhaps that's my ignorance speaking, in fact, most likely it is I'm guessing. When BEorP mentioned checking the wave form of the SPO2 my immediate thought was, "Well, I guess I could do that.." but I never have, and in fact had forgotten that it was even an option. I've just never given the pulse ox enough respect to want to go so far. Either is says what I expected it to when I put it on, or it doesn't. If it doesn't then I start to follow paths to try and verify which of us is right.

It's not about, "I'm so smart I don't need machines.", but "I want to be so competent so as not to be reliant on machines." A different mind set I believe.

Dwayne

[Just Plain Ruff]

So what happens to providers when their equipment fails.

Waht about that catastrophic failure where all the battery powered devices fail? What are your steps now.

You have no battery powered equipment!!!

[Code Whisperer]

1. As long as there is no reason to suspect CO and the patient doesn't have any obscure conditions that could impact SpO2 (e.g. methemoglobinemia), I trust my SpO2 when there is a good waveform. Rarely will I consider an SpO2 reading without viewing the waveform.

This. If the waveform is good, I will consider the SpO2 reading as part of the assessment. If not, it means nothing to me. However, if there is any doubt or if the initial SpO2 is low, I will use ETCO2 to see what's really going on and to help me choose a treatment plan. Also, you can try moving your sensor around to different fingers (or toes) and see what type of results you get. If you have the hard sensors, try using one of the disposable ones to obtain a better reading.

[mobey]

The old mantra says "treat the patient, not the equipment" and I believe that 100%.

Hope I'm never in your remote area when I'm in a perfusing v-tach, or silent MI, or,or,or.......