AED use in a moving ambulance

[Handsome Robb]

First thing should you be transporting a dead pt? Why not work them on scene and either call it or get ROSC and transport. But that is besides the point I suppose.

My guess is BLS service. Correct me if I'm wrong, we use all ALS so all codes get worked where they are and we don't transport unless it's a refractory rhythm or we get ROSC. I'm not super familiar with BLS agency protocols regarding arrests seeing as I have never worked in one. I do know that rapid transport is emphasized in pretty much all EMS even at the paramedic level in the current education system.

My biggest worry about the AED when moving is an over-zealous provider immediately defibbing a patient as soon as they hear the AED say it without checking for a pulse first. The first thing that comes to mind is V-tach with pulses since the AED will see it as VT and can't analyze if it has pulses with it or not, that responsibility lies with the provider.

 

[SoCal911]

Ever grabbed AED pads, hit analyze and shook your fingers (with the pads on your finger)? Itll say shock advised... My guess is using the AED with the rig moving would have the same effect.

 

[Handsome Robb]

Ever grabbed AED pads, hit analyze and shook your fingers (with the pads on your finger)? Itll say shock advised... My guess is using the AED with the rig moving would have the same effect.

Just like "white lead CPR".

Next time you're in class and put someone on the monitor tap the end of the white lead at the same pace you would be doing CPR and watch the monitor. h34r:

 

[Aprz]

I actually haven't heard of it before. I wanna see.

 

[Simusid]

Let me preface this reply by saying (so as not to start an argument) I'm not saying the guidance in textbooks that you should stop a moving vehicle is wrong, or that it AEDs can't improperly interpret artifact as v-fib or that you should do anything differently than your own personal clinical judgement dictates in a given situation.

Since for once, I am qualified to render an expert opinion in this forum, I'm going to do so The question is, is it possible to design an algorithm that can distinguish road noise from v-fib and the answer is yes. You may think the two look the same but in fact they are very different. When you view a signal on the monitor you are viewing it in the time domain, which is a natural view for a human.

For analysis, it is often more interesting to view a signal in the frequency domain.... this includes some fun or scary math (depending on your point of view) called a Fourier Transform (often just FFT). Here is an example of the frequency response of some road noise:

http://binary-services.sciencedirect.com/content/image/1-s2.0-S1361920911001313-gr1.sml
(very small pic, you'll have to ctrl-+ to enlarge it)

and here is an example spectrum of v-fib
http://europace.oxfordjournals.org/content/early/2011/04/13/europace.eur105/F1.expansion.html

Note the spectra are very different and it's certainly possible to write very smart algorithms to distinguish the two.

Flawlessly? Nope. Implemented in every AED? Probably not. Treat the patient not the monitor? Yup!

 

[preggoeggo]

I haven't had to AED a pt yet, but I've heard that if the AED won't find a shockable rhythm, hit the rumble strip on the side of the road...Joke? I'm not so sure :unsure:

 

[airborne2chairborne]

I think the time for transport is the deciding factor, the New England Journal of Medicine did a study in 2008 on defib time vs survival rate, until you hit the 4 minute mark there's very little change in survival rate (40% at 1 and 2 minutes, 35% at 3, and 25% at 4).

cant post links yet (guess I need 5 posts)

 

[pghboy2011]

I don't think that cardiac arrests should ever find themselves in an ambulance to begin with. CPR and defibrillation works. Unlike wine, cardiac arrests don't get better with age.

That's almost silly, you'll need to get that patient to the hospital as soon as it's safe to move them, it's not like you just get their heart going again, and wish them the best. With that being said, once you get them going, and in the ambulance, depending on what caused it, they will likely go back into cardiac arrest.

 

[Medic Tim]

That's almost silly, you'll need to get that patient to the hospital as soon as it's safe to move them, it's not like you just get their heart going again, and wish them the best. With that being said, once you get them going, and in the ambulance, depending on what caused it, they will likely go back into cardiac arrest.

I am pretty sure he means only transport if ROSC is achieved. Some services still wait an additional 10 min or so.

 

[pghboy2011]

I am pretty sure he means only transport if ROSC is achieved. Some services still wait an additional 10 min or so.

Never and Always aren't used in the medical field for a reason....is it possible to go back into cardiac arrest from ROSC? Of course...it's less likely, but it's possible, even with the 10 minute wait.

 

[Medic Tim]

Never and Always aren't used in the medical field for a reason....is it possible to go back into cardiac arrest from ROSC? Of course...it's less likely, but it's possible, even with the 10 minute wait.

there are always exceptions to the rule and times where you have to work with the hand you were given. that said

Unless you have an autopulse or something similar you are doing no favors to your pt. The pt stands the best chance getting worked on scene where cpr can be most effective and defibrillation can be prompt. It is also much safer for the crew.

 

[RustyShackleford]

I don't transport dead patients, I don't work for the funeral home.