# PEEP in BLS?



## NysEms2117 (Dec 18, 2016)

Im an EMT-B, but do not ride on a BLS rig, are PEEP(Positive end-expiratory pressure) valves commonly used in BLS? Are they allowed to be used in BLS? I've seen countless videos of how PEEP is helpful, if used PROPERLY. 


~Andrew


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## NomadicMedic (Dec 18, 2016)

Yes. We have a PEEP valve on all of our BVMs.


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## gonefishing (Dec 18, 2016)

NysEms2117 said:


> Im an EMT-B, but do not ride on a BLS rig, are PEEP(Positive end-expiratory pressure) valves commonly used in BLS? Are they allowed to be used in BLS? I've seen countless videos of how PEEP is helpful, if used PROPERLY.
> 
> 
> ~Andrew


Not widely used in BLS.  VERY rare.  Maybe in a rural area or Intermediate rig.

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## gonefishing (Dec 18, 2016)

DEmedic said:


> Yes. We have a PEEP valve on all of our BVMs.


For the life of me was thinking vents! 

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## EpiEMS (Dec 18, 2016)

NysEms2117 said:


> are PEEP(Positive end-expiratory pressure) valves commonly used in BLS? Are they allowed to be used in BLS?



While I wouldn't be surprised if some states have restrictions on the use of PEEP valves for BLS providers, I do generally believe that they are considered acceptable for BLS use. Heck, if we can use CPAP (in many places) we can certainly put a little PEEP valve on our BVMs...


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## gonefishing (Dec 18, 2016)

EpiEMS said:


> While I wouldn't be surprised if some states have restrictions on the use of PEEP valves for BLS providers, I do generally believe that they are considered acceptable for BLS use. Heck, if we can use CPAP (in many places) we can certainly put a little PEEP valve on our BVMs...


Alot of places don't even allow the use of cpap at the bls level.  Such as L.A.  County.  Things are much the same as they were in 1970.  They just allowed emts to use pulse oximetry last year lol

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## VFlutter (Dec 18, 2016)

I can not think of any situation in which you would use a PEEP valve and it not be ALS.


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## VentMonkey (Dec 18, 2016)

EpiEMS said:


> Heck, if we can use CPAP (in many places) we can certainly put a little PEEP valve on our BVMs...


They're achieving the same end-goal. Our CCT division has them, I leave one where I can grab it in our airway bag next to our BVM's, but do still admittedly forget, or the patient is already being bagged while I am setting stuff up; a habit I am trying to break. 

Our ground division does not carry them, though I wish that they did, as well as our fire first responders.

But, more important than the importance of these nifty little buggers would be _*proper delivery of ventilations *_, and subsequently oxygenation. Even without them, an excellent bag-mask technique is most definitely more important, IMHO.


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## VentMonkey (Dec 18, 2016)

Chase said:


> I can not think of any situation in which you would use a PEEP valve and it not be ALS.


The end of a (BLS) BVM.


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## EpiEMS (Dec 18, 2016)

gonefishing said:


> Alot of places don't even allow the use of cpap at the bls level.  Such as L.A.  County.  Things are much the same as they were in 1970.  They just allowed emts to use pulse oximetry last year lol
> 
> Sent from my SM-G920P using Tapatalk



L.A. County scares me...



Chase said:


> I can not think of any situation in which you would use a PEEP valve and it not be ALS.



Absolutely, but there's no reason not to have them on your BLS units (if they might happen upon a patient who'd need PPVs prior to ALS arrival).



VentMonkey said:


> But, more important than the importance of these nifty little buggers would be _*proper delivery of ventilations *_, and subsequently oxygenation. Even without them, an excellent bag-mask technique is most definitely more important, IMHO.



Certainly can't disagree! That's a matter for training -- I always say that I'd like more BVM practice!


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## E tank (Dec 19, 2016)

I'd think it would be next to impossible to maintain any meaningful PEEP with a mask. That'd be some pretty wicked mask ventilation skills.


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## Carlos Danger (Dec 19, 2016)

As was very recently discussed in another thread, PEEP is a good idea any time you are providing positive pressure ventilation.

It isn't any harder to provide good mask ventilation with a PEEP valve than it is without it. I can't think of any reason why BLS personnel would be expected to be able to provide good mask ventilation, but not be able to use a PEEP valve.


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## EpiEMS (Dec 20, 2016)

In resuscitation, how concerned should we be about downsides of PEEP (e.g. barotrauma)?


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## Summit (Dec 20, 2016)

EpiEMS said:


> In resuscitation, how concerned should we be about downsides of PEEP (e.g. barotrauma)?



PEEP valve on a BVM giving you 10 of peep is not going to cause overpressure injury. It is far more likely bad technique (overinflation) would do that which is prevented with training and a pop-off valve.


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## E tank (Dec 20, 2016)

Summit said:


> PEEP valve on a BVM giving you 10 of peep is not going to cause overpressure injury. It is far more likely bad technique (overinflation) would do that which is prevented with training and a pop-off valve.



Agreed...volu/barotrauma is just that...unnecessarily high volumes/pressures for the condition. PEEP only contributes inasmuch as it affects the mean airway pressure...all that said, in low flow, low venous return states like any type of shock or resuscitation, laying off the PEEP and keeping low tidal volumes will promote whatever cardiac output you have to work with.


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## EpiEMS (Dec 20, 2016)

@Summit and @E tank, much appreciated. So it sounds like PEEP is most useful in such situations as CPAP is, but at the point where you have to transition away from CPAP to PPVs, right? Like when your acute asthmatic decompensates to the point where they need PPV rather than NIPPV?


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## E tank (Dec 20, 2016)

EpiEMS said:


> @Summit and @E tank, much appreciated. So it sounds like PEEP is most useful in such situations as CPAP is, but at the point where you have to transition away from CPAP to PPVs, right? Like when your acute asthmatic decompensates to the point where they need PPV rather than NIPPV?



So are you saying that, in general, CPAP is for spontaneous ventilation and PEEP for positive pressure/mechanical ventilation? If so, then yes, that's correct. Am I following you?


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## EpiEMS (Dec 20, 2016)

E tank said:


> So are you saying that, in general, CPAP is for spontaneous ventilation and PEEP for positive pressure/mechanical ventilation? If so, then yes, that's correct. Am I following you?


Yeah, I suppose my question answered itself - if a patient with a complaint that (in a conscious, able to maintain their airway patient) would get CPAP goes unconscious/becomes unable to maintain their airway, PPV with PEEP would be acceptable.


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## E tank (Dec 20, 2016)

EpiEMS said:


> Yeah, I suppose my question answered itself - if a patient with a complaint that (in a conscious, able to maintain their airway patient) would get CPAP goes unconscious/becomes unable to maintain their airway, PPV with PEEP would be acceptable.



Generally speaking, yes. But like I said before, if a low/no blood flow state were to exist, you'd leave off the PEEP and use "smaller" tidal volumes because of the potential to further decrease venous return to the heart.


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## VFlutter (Dec 20, 2016)

E tank said:


> Generally speaking, yes. But like I said before, if a low/no blood flow state were to exist, you'd leave off the PEEP and use "smaller" tidal volumes because of the potential to further decrease venous return to the heart.



Our protocols actually recommend a high volume low rate (10-12ml/kg at 6-8) for hypotensive patients, most often trauma.


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## E tank (Dec 20, 2016)

Chase said:


> Our protocols actually recommend a high volume low rate (10-12ml/kg at 6-8) for hypotensive patients, most often trauma.



Wow...regional differences I guess. That's really surprising given these patients are at higher risk for ALI and 10-12 ml/kg doesn't meet any protective lung strategy at all. As long as the mean airway pressure didn't get too high, venous return would be preserved. Do your protocols recommend PEEP here as well?


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## EpiEMS (Dec 20, 2016)

Chase said:


> Our protocols actually recommend a high volume low rate (10-12ml/kg at 6-8) for hypotensive patients, most often trauma.



What's the rationale behind this, if you don't mind my asking?


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## VFlutter (Dec 20, 2016)

E tank said:


> Wow...regional differences I guess. That's really surprising given these patients are at higher risk for ALI and 10-12 ml/kg doesn't meet any protective lung strategy at all. As long as the mean airway pressure didn't get too high, venous return would be preserved. Do your protocols recommend PEEP here as well?



It is actually the protocol for the largest HEMS company nationwide, not regional. PEEP of 0, I time of 1.



EpiEMS said:


> What's the rationale behind this, if you don't mind my asking?



This podcast sums it up better than I can. The idea being that the ventilator strategy overall allows more time for venous return than conventional lung protective strategy.  

http://podbay.fm/show/595147712/e/1421157181?autostart=1


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## EpiEMS (Dec 20, 2016)

Chase said:


> It is actually the protocol for the largest HEMS company nationwide, not regional. PEEP of 0, I time of 1.
> 
> 
> 
> ...


Thanks very much, @Chase!


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## E tank (Dec 20, 2016)

Chase said:


> It is actually the protocol for the largest HEMS company nationwide, not regional. PEEP of 0, I time of 1.
> 
> 
> This podcast sums it up better than I can. The idea being that the ventilator strategy overall allows more time for venous return than conventional lung protective strategy.
> ...



Thanks for the link. Sounds like the idea is to mitigate the impediment to venous return by avoiding PEEP and allow longer periods of recovery between breaths.

 He really loses me on the relationship between "dead space" and increased intrathoracic pressure though.

 If I hear him correctly, he's saying that "dead space" is lost with smaller tidal volumes which somehow contributes to rising intrathoracic pressures which causes hemodynamic instability. Kind of like he's saying that dynamic hyperinflation/breath stacking is occurring, but that can't be what he's saying.

Is there a paper you could point me toward that is more clear? I must confess that I've never heard of this type of ventilation strategy and I'm interested in learning more about it.


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## VFlutter (Dec 20, 2016)

E tank said:


> Thanks for the link. Sounds like the idea is to mitigate the impediment to venous return by avoiding PEEP and allow longer periods of recovery between breaths.
> 
> He really loses me on the relationship between "dead space" and increased intrathoracic pressure though.
> 
> ...



Ya I was not following that as well. He focused heavily on dead space ventilation during our ventilation modules but I am not sure I completely agree or see it in practice. Maybe he is saying since there is fixed dead space loss with each breath that what we assume are normal physiologic tidal volumes are actually much less at the alveolar level and that the compensation would be increasing respiratory rate causing more time with increased intrathroacic pressures. Assuming you have 150ml of dead space ventilation with each breath then lowering the respiratory rate would mean encountering that dead space less often? Not sure. 

I will try to find the reference articles on our training modules.


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## VentMonkey (Dec 20, 2016)

E tank said:


> Generally speaking, yes. But like I said before, if a low/no blood flow state were to exist, you'd leave off the PEEP and use "smaller" tidal volumes because of the potential to further decrease venous return to the heart.


Just curious, would you mind sharing your background with the group?


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## Carlos Danger (Dec 20, 2016)

The reasoning behind the low frequency ventilation strategy in hypotension is simple: if you minimize the amount of time that the lungs are inflated, then you minimize mean intrathoracic pressure. That's why the short i-time is important. The larger tidal volumes are simply to maintain an adequate minute volume with the lower respiratory rate. 6 breaths with an i-time of 1 and you get only 9 seconds a minute or so at the peak intrathoracic pressure. 10 breaths/min with an i-time of 1.5 and you get more than twice the amount of time at peak pressure.

I have to say though, that 10-12 ml/kg seems ridiculously high. Not only do we know that to be hard on the lungs, but you just don't need that much to maintain an adequate minute volume in a well-sedated patient. If you assume 4 l/m is an adequate minute volume in a sedated patient and you only want to ventilate 6 times a minute, then you only need 660 cc tidal volume. If you are willing to accept a little higher Pac02 then you can go even lower on your vt. I also don't see the rationale behind zero PEEP. 

I don't see what anatomic dead space has to do with anything at all here. Anatomic dead space is always present and always constant, no matter what vent strategy you are using or why. The guy in the podcast honestly didn't seem to know much about what he was talking about. I've heard him say some wacky stuff in other podcasts too, including a couple things that were outright untrue.


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## VFlutter (Dec 20, 2016)

Remi said:


> The guy in the podcast honestly didn't seem to know much about what he was talking about. I've heard him say some wacky stuff in other podcasts too, including a couple things that were outright untrue.



Unfortunately the majority of our training on ventilator management was written by him. Some of it was good but a lot of it was infuriating


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## E tank (Dec 20, 2016)

Remi said:


> The reasoning behind the low frequency ventilation strategy in hypotension is simple: if you minimize the amount of time that the lungs are inflated, then you minimize mean intrathoracic pressure. That's why the short i-time is important. The larger tidal volumes are simply to maintain an adequate minute volume with the lower respiratory rate. 6 breaths with an i-time of 1 and you get only 9 seconds a minute or so at the peak intrathoracic pressure. 10 breaths/min with an i-time of 1.5 and you get more than twice the amount of time at peak pressure.
> 
> I have to say though, that 10-12 ml/kg seems ridiculously high.



So the goal is minimizing the intrathoracic pressure...which we do with protective  lower tidal volumes.( I get that PEEP becomes more important with lower tidal volumes, but it can be added as the patient is stabilized.) I'm still lost on the point. Seems like robbing Peter to pay Paul.  Additionally, won't peak pressures be higher with shorter i-times?

If an entire HEMS system is using this, my assumption is that folks smarter than me have vetted it...I'm just interested in where it comes from.


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## Carlos Danger (Dec 20, 2016)

E tank said:


> If an entire HEMS system is using this, my assumption is that folks smarter than me have vetted it...I'm just interested in where it comes from.



Well, I agree.....there must be something to it. I'd like to read something on it. But there's gonna have to be some pretty overwhelming evidence to convince me that 10-12 ml/kg is a good idea.


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## E tank (Dec 21, 2016)

VentMonkey said:


> Just curious, would you mind sharing your background with the group?



Sure...never did that, sorry...backround in EMS, emergency/trauma, adult and peds CC, current incarnation CT anesthesia CRNA. Started on the ambulance in 1982 but I'm more well preserved than the years might imply


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