Arterial Hyperoxia Post-Resuscitation = BAD

18G

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Just saw this published study on JEMS.com and found it very interesting. It's come to light how hyperoxemia in the MI patient can increase mortality and now some research to show too much oxygen is a bad thing for cardiac arrest patients.

O2 administration guidelines for EMS has always been a major pet peeve of mine. Everyone does NOT need 15lpm by NRB!


http://www.jems.com/article/patient-care/arterial-hyperoxia-following-r
 
If oxygen is indicated, most patients only require a few litres on a nasal cannula.

Fifteen litres a minute is simply unheard of here.
 
I think I wrote something on this.



several times...

Nice to see people catching on. :)
 
Great info... I do not know how it is now for basics, but it was not that long ago I took my EMT-B in 2002. I remember at that time they where really pushing 3 things in training. BSI/scence safe, ABS's, and 15 LPM NRB.
 
Great info... I do not know how it is now for basics, but it was not that long ago I took my EMT-B in 2002. I remember at that time they where really pushing 3 things in training. BSI/scence safe, ABS's, and 15 LPM NRB.

I took basic in 07. It was the same way. My instructor used to always say "Go big or go home"

I didn't really agree with him, but what was I going to say? I was a clueless nwebie then (and now I'm just a clueless 3 year intermediate! lol) and it made sense then.

Vene, I'd like to read what you wrote on this. Is it on the forum? If so, do you have a link to the post?


Brown, that about sums up 80% of American EMS.
 
6 liters by nasal cannula would certainly clear the sinuses!

There's a bunch of reasons why hyperoxemia and high FiO2 can be detrimental: increased myocardial workload in MI, production of oxygen reactive species (bad in strokes, MI and, well, everything) VILI, absorption atelectasis... The list goes on

Of course withholding O2 from someone who needs it is bad too! Oh, the conundrum!
 
Just in case someone isn't reading the comments.


I think one of the big problems is that EMS, especially EMS education, tends to treat oxygen as some sort of miracle drug that gives EMS providers a chance to save everyone from a stubbed toe to a CVA to a cardiac arrest. Why else is failure to give high concentration of oxygen (at least they aren't calling it "high flow") a critical failure for, of all things, a medical assessment? Shouldn't the assessment be driving the treatment? If not, why even do an assessment in the first place. It's like saying, "Assessment tools be damned, if you're a paramedic treating a patient with an ALOC, it's D50 and narcan. Assessment (including point of care lab values like blood glucose levels) and patient history (including HPI) be damned."


Medic Marshall asks, "Are there only certain conditions under which oxygen should be administered?"

Why not? What other intervention is given to all patient regardless of assessment? We don't transport lights and sirens for all patients (I'd argue that the decision to use emergency transport over regular transport is as much an intervention as anything else). More and more trauma patients aren't being put through spinal immobilization for no better reason than they suffered a traumatic insult regardless of how minor it was. Why should we continue with the "Well, ambulance transport means a NRB" attitude?

While working as an EMT-B, I used a NRB once on a patient that fell into the "Well, I can't do anything else, so maybe...." column. The nurse receiving the patient asked innocently why the patient was on a NRB and the only thing I could think of was "protocol." In my time as an EMT, I have never felt more dirty or a failure than after I uttered those words, including all of the times I've made mistakes or missteps because we, as a supposed profession, should always be able to justify our treatment interventions based on our education, training, and assessment and a "I couldn't think of anything else and it's 'benign" is a failure. I vowed never to make that mistake again.

Of course my attitude of using assessment based treatment clashes with another JEMS columnists views that the only true source of education is the initial training (unfortunatly, my comments on that column was lost in the transfer to the new web design).
http://www.jems.com/article/training/use-these-tips-ems-professor


Sincerely,
Joe P. MS, NREMT-B, OMS-II (only including these since they're relevant to this comment).
 
Of course withholding O2 from someone who needs it is bad too! Oh, the conundrum!
Isn't that why we're supposed to be professionals trained in assessment? Maybe they took the "EMT" away from the paramedic title a little too soon.
 
Of course withholding O2 from someone who needs it is bad too! Oh, the conundrum!

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Couple of issues. One is that you have to be really careful comparing unequal groups. So comparing patients in the ICU (most of whom were probably on ventilators) post cardiac arrest to run of the mill patients prehospital is a bit of a stretch. I'm skeptical that the amount of 02 most patients get in a 15 or 20 minute EMS transport is going to harm them. The same argument has been made with COPD patients. Yes, if you keep them on 02 for 12 hours you might decrease their respiratory drive, but this shouldn't play into prehospital management.

It should be noted that in the paper in question there was a correlation between arterial 02 levels and patient death. Not a relationship between amount of 02 given, but their blood level. So maybe something in these patients made them better able to oxygenate but also increased mortality, maybe these patients were treated more aggressively on the vents because they were sicker somehow. Correlation does not equal causation.

It's an interesting study but you need to read it critically and there needs to be a lot more data before everyone starts throwing out their 02 tanks.
 
CoI'm skeptical that the amount of 02 most patients get in a 15 or 20 minute EMS transport is going to harm them.

HUGE HUGE assumption. Think about how quickly a patient who needs oxygen improves after you administer it. Do you think it takes any less time affect anyone without some sort of oxygen carrying problem?

Remember, we used to think that backboarding everyone wasn't a big deal and then we learned how quickly tissue break down happens. Never assume that 15 or 20 minutes isn't enough time to cause harm.
 
This looks at post cardiac arrest hyperoxia and hypoxia in the ICU, over a long (by our standards) period of time - "Patient inclusion criteria were age older than 17 years, nontraumatic cardiac arrest, cardiopulmonary resuscitation within 24 hours prior to ICU arrival, and arterial blood gas analysis performed within 24 hours following ICU arrival."

This really doesn't have any bearing on supplemental O2 in most EMS patients. The author of the article launches straight into the example of a the first responder putting oxygen on a patient with stomach cramps. How are the two related? If its simply that this is the first he's heard of O2 not being chicken soup, then he should really read more.

The only way in which this is relevant to EMS that I can see is that we may, sometime in the future, be looking at reduced FiO2 in some post arrest patients, but I don't see how that would happen without ABG results.
 
That 20 minutes of oxygen by the ambos won't make a COPD patient hypercapenic too right?
 
HUGE HUGE assumption. Think about how quickly a patient who needs oxygen improves after you administer it. Do you think it takes any less time affect anyone without some sort of oxygen carrying problem?

Since 02 clearly helps so many patients, the burden of proof is on those who suspect that it is harmful in prehospital patients. Secondly, the mechanism of the proposed harm is unknown, so while their p02 may quickly rise there is likely a certain amount of time at a high p02 needed for harm if the mechanism is something like free radical generation.

We very might get to the point where we are limiting who gets 02, but we're not there yet. This sort of article scares me because there are people who are clearly reading it and deciding to change their practice without understanding what the article actually looks at.
 
Since 02 clearly helps so many patients,

I'm sorry... I don't buy that even a majority of people who gets supplemental oxygen by EMS responders actually need supplemental O2, especially at the quantity provided.
 
I'm sorry... I don't buy that even a majority of people who gets supplemental oxygen by EMS responders actually need supplemental O2, especially at the quantity provided.

Sold! I think out of my last 10-15 patients one got a couple litres on a nasal cannula because he was a bit short of breath.
 
Since 02 clearly helps so many patients, the burden of proof is on those who suspect that it is harmful in prehospital patients. Secondly, the mechanism of the proposed harm is unknown, so while their p02 may quickly rise there is likely a certain amount of time at a high p02 needed for harm if the mechanism is something like free radical generation.

We very might get to the point where we are limiting who gets 02, but we're not there yet. This sort of article scares me because there are people who are clearly reading it and deciding to change their practice without understanding what the article actually looks at.

Sorry but what? I already do not give 100% of my patients oxygen, and it's because 100% of them don't need it. More like 5-10%, maybe. Just because the mechanism is unknown doesn't negate the reality that harm is caused. We don't always understand how things work, but they do.
 
To be clear, I'm not saying that all patients should get 02. I'm arguing that those who currently have an indication for 02 should still get it. I'm arguing that a study looking at post arrest ICU patients on vents getting ABGs should not change how EMS determines oxygen therapy. And it sounded like a lot of people were saying exactly that based on a JEMS summary of the article.

The last thing we need right now is a bunch of people bringing hypoxic patients to the ED, puffing away because they were worried about causing hyperoxic states.
 
Isnt this study looking at hyperoxia s/p arrest?

As far as I know most systems still deliver one hundred percent oxygen during a resuscitation attempt. Maybe another vote for passive ventilation.

And I agree way to many EMS patients recieve O2 but thats what they teach now. We were taught patient assessment skills not high flow O2 and call the medics but then again my class wasnt 120 hours either.
 
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