When do you use bvm & Nonrebreather?

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Sknight2012

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How do you determine when you should use a non rebreather and when you would use a bvm on a patient ?
 
Short answer: NRB if the patient is breathing, BVM if the patient is not.

Actual answer: It depends.

The NRB is an oxygen delivery device only. The patient has to moving air adequately for it to be effective. The BVM is a ventilatory device. It provides assisted ventilations to a patient without an adequate minute volume or not moving air at all.
 
What is the purpose of a non rebreather? What is the purpose of a BVM?
 
A NRB provides supplemental O2 to a person with sufficient ventalation, but less than adequate O2 level/exchange.

A BVM ventilates a patient who is not moving enough air (insufficient RR and/or shallow ventilations).
 
Ventilation vs. oxygenation. Two different things. Look those up, and it should come a little easier.

But yeah stx hit the nail on the head.
 
While we are on the subject of oxygenation and ventilation, let's remember

1. Most patients who are hypoxic generally only need a couple of litres of oxygen via nasal prongs or a simple mask. Non-rebreather masks with high flow rates (10l/min) are reserved for the very hypoxic; such as somebody who has acutely decompensated cardiac failure or asthma. Hb are almost totally, or totally, filled to capacity with oxygen (I forget which) and only about 2-3% of O2 is dissolved in plasma (rest is carried on Hb) so you can give somebody as much oxygen as you like (or ventilate them as fast as you can) but it won't change what is happening on a cellular level if they are already normoxaemic.

2. Hypoxaemia and ischaemia are not the same thing. Specifically, myocardial ischaemia won't be cured by giving oxygen, and in-fact, it is very likely to make things worse because hyperoxaemia causes small capillary sphincters to close and may limit coronary blood flow. The latter means oxygen is also bad for patients with an ischaemic stroke.

3. Ventilate slowly. Think about each breath and the minute volume you are trying to achieve. Blindly getting excited and squeezing the bag a billion times a minute (which is very easy) is not going to do the pt any good, and can do them harm for example if they have TBI, asthma or are in cardiac arrest.
 
I have used a BVM on patients who are breathing too fast for their own good, and are conscious. You keep the mask sealed to the face and bag them about 8-10 times a minute. Fun to talk them through that, but easier than waiting for them to pass out.

I have been threatened with it twice by paramedics here where I work when I was on the way to the hospital for severe asthma issues: you breathe 80 times a minute and it makes people nervous.
 
They may be breathing on their own which may make you think Nrb but they may not have sufficient tidal volume which would need a bvm.
 
Can you use a bvm on a conscious patient? How about conscious patient sitting up on a chair?
 
jenn14er said:
Can you use a bvm on a conscious patient? How about conscious patient sitting up on a chair?
Click to expand...
Can you? Yes. Is it likely to work? Depends on how with it they are and if they will allow you to do it. As long as you are able to get a good seal then yes you can do it in a chair but will run into the same issues as above.
 
jenn14er said:
Can you use a bvm on a conscious patient? How about conscious patient sitting up on a chair?
Click to expand...

I still remember call I did early on in my career:
Respond for the 80yo with SOB. She's tripodding in the kitchen, 1-word answers, but hey, she doesn't look like she's in thaaaaaaat much distress... We throw a NRB on her and carry her out to the truck. By the time we put her in the back, she has completely stopped breathing. Oopsie daisy!

In retrospect, she probably didn't look dramatically sick because she was so far down the decompensated side of the curve, and was running out of energy to keep up with her breathing. We took her out of the tripod position and put her on a stretcher in Fowler's position, and it was just too much.

She was mostly conscious and alert, just not breathing! Pulled out a BVM, got behind her and started bagging. Sats came up, CO2 went down, imagine that! That was the only time I've used a BVM on a conscious patient sitting up in a chair, but it seemed like it worked well enough. It's tough to do while the ambulance is moving though - you're semi-squatting behind the head of the stretcher, bouncing around, trying to keep a seal...
 
If only BVMs came with straps like Anesthesia masks. BVM +PEEP @ 15 lpm works great, if you can maintain a seal, on conscious patients in severe distress as you are setting up your NPPV or preparing for RSI. Or if you NPPV masks are non-vented you can just use that.


4-1054-inuse_web.jpg
 
Gurby said:
I still remember call I did early on in my career:
Respond for the 80yo with SOB. She's tripodding in the kitchen, 1-word answers, but hey, she doesn't look like she's in thaaaaaaat much distress... We throw a NRB on her and carry her out to the truck. By the time we put her in the back, she has completely stopped breathing. Oopsie daisy!

In retrospect, she probably didn't look dramatically sick because she was so far down the decompensated side of the curve, and was running out of energy to keep up with her breathing. We took her out of the tripod position and put her on a stretcher in Fowler's position, and it was just too much.

She was mostly conscious and alert, just not breathing! Pulled out a BVM, got behind her and started bagging. Sats came up, CO2 went down, imagine that! That was the only time I've used a BVM on a conscious patient sitting up in a chair, but it seemed like it worked well enough. It's tough to do while the ambulance is moving though - you're semi-squatting behind the head of the stretcher, bouncing around, trying to keep a seal...
Click to expand...


Thanks for sharing! That is so cool
 
VFlutter said:
If only BVMs came with straps like Anesthesia masks. BVM +PEEP @ 15 lpm works great, if you can maintain a seal, on conscious patients in severe distress as you are setting up your NPPV or preparing for RSI. Or if you NPPV masks are non-vented you can just use that.


4-1054-inuse_web.jpg
Click to expand...

I remember stealing a connector piece from the ED at some point to be able to hook up our BVM to whatever brand of CPAP we used. Don't think I ever actually used it though.
 
Gurby said:
I remember stealing a connector piece from the ED at some point to be able to hook up our BVM to whatever brand of CPAP we used. Don't think I ever actually used it though.
Click to expand...
The service I work for uses the Flow-Safe CPAP. Those masks connect to a BVM without an adapter, and I've had pretty good success with it. The Flow-safe masks + some PEEP and high flow O2 can also make a poor-man's BiPAP if you can get the bag squeezing timing down.
 
Every CPAP mask I've ever used took the BVM without issue (and vent circuit for that matter)
 
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