Oxygen only vs. Ventilation question

[ethomas4]

Hi, 2nd week EMTB student here,

My teacher gave us sheet that says,

"If breathing is adequate:
If patient is breathing faster than 20/min and slower than 12/min, use non-rebreather mask (high flow oxygen)"

my question is: so if a patient is breathing only 2/min we wouldn't begin ventilation with a BVM connected to 15l of supplemental oxygen ?

I would consider a breath rate of under 12 in an adult to be inadequate
I do not understand why our sheet says give oxygen only if outside normal breathing ranges.

Please help

 

[JPINFV]

Methinks that there's a typo since thats bass ackwards.

NREMT verson of "Medical Care" (I think I just threw up in my mouth):

Adequate ventilation-> NRB
Inadequate ventilation either due to rate or quality -> BVM.

 

[Shishkabob]

It's kind of a confusing set up. It says "If breathing is adequate", so if it's adequate at 2bpm, why fix it? Granted 2breaths a min will never be adequate, but that's how they phrased it which leads me to believe it's a typo.


Generally if breathing is inadequate you will assist ventilation. Could be too fast, too slow, or not deep enough. If they have adequate tidal volume, equal chest rise, and so on, you might just have to give supplemental oxygen. You just have to use your assessment to determine when it's needed.

 

[ethomas4]

THanks,

so, adequate ventilation = NRB mask, Inadequate, either due to rate or quality, = BVM (generally speaking here)

so where does the nasal cannula come in? My sheet says "if breathing is within normal limits with good tidal volume, use a nasal cannula."

is that correct or another typo? My book says that my decision will be based on my decision...whether or not to use NRB or nasal cannula


thank you

 

[JPINFV]

The book is correct, however for most testing scenarios, the indication for a nasal canula the patient won't tolerate a NRB.

 

[Melclin]

I suppose the idea is that outside those normal ranges, there might be some kind of pathology that will be corrected with supplemental oxygen.

I'm sure that sheet is given with the assumption that if the pt is not breathing with an adequate tidal volume, that you should perform some kind of manual ventilation.

While oxygenation is a pretty complex process, there is a relationship between three factors that you want to be familiar with at this stage that affect the choices you make with supplemental oxygen as I see it, but others may disagree (I always like to point out, I'm only a student myself).

1. Fraction of inspired oxygen (FiO2) - this is the percentage of what ever is going in that is made up of O2, remembering that the air we breath is 21 percent oxygen, the rest being mostly nitrogen. So the FiO2 of air is 0.21, but lets write it as a percentage for now - 21%. (You nasal canulae and simple face masks can offer anywhere between 23% and ~60% oxygen depending on the flow rate from the regulator, respiratory rate and tidal volume).

2. Tidal Volume (Vt) - How much air/gas is taken in with each breath.

3. Respiratory Rate (RR) - How many breaths are taken each minute.

Hop on google and just quickly read up on their relationships, especially the importance of adequate minute volume. I think then the issue may become clearer.

You are, of course, right. If a person is 'breathing' at two a minute, you must manual ventilate them; an O2 mask in not appropriate. However, exactly where you decide that a person's respiratory rate becomes inadequate for supplemental oxygen, and that they need to be manually ventilated is not always clear cut. As an EMT, I'm sure you will have a RR number bellow which you must start ventilating. So for tests and so on, remember that, however, understand that oxygenation and ventilation physiology and treatment modalities are very much more complicated that just RR and still far more complex than just the three factors I mentioned.

http://people.eku.edu/ritchisong/301notes6.htm -- This web page may help you to answer some of your questions. I stumbled on it the other day, and it looks pretty good. I haven't heard any objections to it yet.

 

[ethomas4]

thanks melclin for the link

 

[joeshmoe]

ethomas.....You seem to be confusing difficulty breathing or respiratory distress, with inadequate breathing. A respiratory rate outside 12 to 20 might indicate breathing difficulty and call for supplemental oxygen, but it doesnt necessarily mean INADEQUATE breathing.

Inadequate breathing means the rate/depth is far enough outside normal ranges that it cannot support life unless it is corrected(ventilations). One can have difficulty breathing and still be breathing adequately for the moment.
As for what constitutes inadequate breathing, the others have already hit on it some.
When you should assist ventilations is probably one of the trickier things you will have to know.

I should also add that for your purposes as an EMT basic student, any patient exhibiting S/S of breathing difficulty will get at least a NRB, providing they can tolerate the mask. Dont let people confuse you with scenarios like a pt with lung disease who may have a hypoxic drive, they still get a NRB, at least to the hospital.

You will generally find that as a basic there are few situations that dont call for at least a NRB. When you're doing clinicals and a paramedic tells you to use a nasal cannula in one of these situations, dont argue with him lol they have a depth of knowledge well above a basic and know when its not gonna make a difference.