CPR or Defibrillation First - Witnessed Arrest

18G

18G

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Had a minor dispute about what the proper action is on a witnessed arrest this evening so wanted to seek opinions.

The scenario is: transporting a patient and patient arrests. What do you do first treatment wise? Shock or CPR?

I informed my preceptee that she should shock immediately. An EMT told me that was wrong and that you're supposed to do CPR first even though its witnessed. I strongly disagree.

This is why I disagree.

Defibrillation is the definitive treatment for cardiac arrest. The AHA says to start CPR while the defibrillator is retrieved. Well if ya got one six inches away from ya doesnt that qualify as defibrillator being retrieved and that you should use it immediately????

I understand the theory behind CPR first as an attempt to perfuse the myocytes so that they respond more favorably to the shock. But the research states that no solid evidence supports or refutes CPR before defibrillation. But what is known is that immediate defibrillation works.

My thinking is this patient just coded and they aren't real hypoxic yet so why not shock them first and then start CPR? By starting CPR first we are delaying a crucial treatment.

What do others think?
 
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The current standard is if it's witnessed to defibrillate immediately, but if it's not witnessed or long down time, there is little research to support whether doing a cycle of CPR (2 minutes) or defibrillating immediately is better. They recommend that you do CPR while getting the defibrillator ready, but nothing about whether you actually need to delay defibrillation to complete the full 2 minutes.

CPR Before Defibrillation
During treatment of VF/pulseless VT healthcare providers must ensure that coordination between CPR and shock delivery is efficient. When VF is present for more than a few minutes, the myocardium is depleted of oxygen and metabolic substrates. A brief period of chest compressions can deliver oxygen and energy substrates and “unload” the volume-overloaded right ventricle, increasing the likelihood that a perfusing rhythm will return after shock delivery.141

Performing CPR while a defibrillator is readied for use is strongly recommended for all patients in cardiac arrest (Class I, LOE B). Analyses of VF waveform characteristics predictive of shock success have documented that the shorter the time interval between the last chest compression and shock delivery, the more likely the shock will be successful.141 A reduction of even a few seconds in the interval from pausing compressions to shock delivery can increase the probability of shock success.142

The value of intentionally delaying defibrillation to perform CPR is less clear. One randomized controlled trial (RCT)143 and one clinical trial144 involving adults with out-of-hospital cardiac arrest not witnessed by EMS personnel showed that survival was improved by a period of CPR performed before the first defibrillation shock when the EMS response interval was >4 to 5 minutes. But 2 RCTs145,146 demonstrated no improvement in ROSC or survival to hospital discharge in patients with out-of-hospital VF or pulseless VT who received CPR from EMS personnel for 1.5 to 3 minutes before defibrillation, regardless of EMS response interval. At this time the benefit of delaying defibrillation to perform CPR before defibrillation is unclear (Class IIb, LOE B).
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Source: http://circ.ahajournals.org/content/122/18_suppl_3/S729.full#sec-32

https://www.youtube.com/watch?v=riUAFkV7HCU

^Clearly can see right ventricular fluid overload. Edit Cannot get the Youtube thing to work. Just click the link to see.

In a short amount of time, I don't imagine that would happen.

I actually did read something though, I believe I saw it on ems12lead Facebook group Prehospital 12-lead ECG, that recommended doing 2 minutes of CPR first regardless of if it was witnessed. The research showed that the mortality rate was higher if it was witnessed and defibrillation was attempted first without chest compressions. At this time, I cannot find the article, but I will be browsing for it so I can post it here.

Another thing I can think about is what TomB said about shocking a patient into asystole.

TomB said:
Yes, if the pre-shock coronary perfusion pressure is less than 15 mm Hg you will almost always shock the rhythm into asystole. This is why it's extremely important to perform comrpessions while the capacitor is charging and minimize the peri-shock pause. The pre-shock pause is more important that the post-shock pause but both are important.
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Source: http://www.emtlife.com/showthread.php?p=483742#post483742

I'm not how fast the coronary perfusion pressure drops when trying to ready the defibrillator, but I think that could be another thing that would make somebody FOR doing chest compressions prior to defibrillation even if witnessed.

I will update this post when I find that article I am talking about.

Edit I cannot find the article after browsing the Facebook group page several time. I am positive it exists somewheres, but I can't find it. :[ Maybe Christopher or TomB will drop by?
 
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Roger this

Aprz said:
The current standard is if it's witnessed to defibrillate immediately, but if it's not witnessed or long down time, there is little research to support whether doing a cycle of CPR (2 minutes) or defibrillating immediately is better. They recommend that you do CPR while getting the defibrillator ready, but nothing about whether you actually need to delay defibrillation to complete the full 2 minutes.


Source: http://circ.ahajournals.org/content/122/18_suppl_3/S729.full#sec-32

https://www.youtube.com/watch?v=riUAFkV7HCU

^Clearly can see right ventricular fluid overload. Edit Cannot get the Youtube thing to work. Just click the link to see.

In a short amount of time, I don't imagine that would happen.

I actually did read something though, I believe I saw it on ems12lead Facebook group Prehospital 12-lead ECG, that recommended doing 2 minutes of CPR first regardless of if it was witnessed. The research showed that the mortality rate was higher if it was witnessed and defibrillation was attempted first without chest compressions. At this time, I cannot find the article, but I will be browsing for it so I can post it here.

Another thing I can think about is what TomB said about shocking a patient into asystole.


Source: http://www.emtlife.com/showthread.php?p=483742#post483742

I'm not how fast the coronary perfusion pressure drops when trying to ready the defibrillator, but I think that could be another thing that would make somebody FOR doing chest compressions prior to defibrillation even if witnessed.

I will update this post when I find that article I am talking about.

Edit I cannot find the article after browsing the Facebook group page several time. I am positive it exists somewheres, but I can't find it. :[ Maybe Christopher or TomB will drop by?
Click to expand...


I believe in a prior post it was cited that it takes about fifteen compressions to reestablish haemodynamic pressure if CPR is halted. One might add, that means losing CPR-effective circulation over the time for fifteen compressions, plus the downtime which precipitated the catch-up. It also presumes that you CAN "catch-up".

Trouble with "shock first" is an AED would not shock most conditions where the very promptly administered shock could make a difference (electrocution, atrial fib related hypotension, unknown etc). Different if you are using a manual defib, but is it in protocols?

How about have electrodes in place for every patient suspected of needed enroute jolts? Tap the "CHARGE" switch or button, start CPR, when the light is green switch to "shock", then CPR until proven unnecessary (pt threatens to sue).
 
Thanks for the links and feedback. I appreciate it.
 
18G said:
Had a minor dispute about what the proper action is on a witnessed arrest this evening so wanted to seek opinions.

The scenario is: transporting a patient and patient arrests. What do you do first treatment wise? Shock or CPR?

I informed my preceptee that she should shock immediately. An EMT told me that was wrong and that you're supposed to do CPR first even though its witnessed. I strongly disagree.

This is why I disagree.

Defibrillation is the definitive treatment for cardiac arrest. The AHA says to start CPR while the defibrillator is retrieved. Well if ya got one six inches away from ya doesnt that qualify as defibrillator being retrieved and that you should use it immediately????

I understand the theory behind CPR first as an attempt to perfuse the myocytes so that they respond more favorably to the shock. But the research states that no solid evidence supports or refutes CPR before defibrillation. But what is known is that immediate defibrillation works.

My thinking is this patient just coded and they aren't real hypoxic yet so why not shock them first and then start CPR? By starting CPR first we are delaying a crucial treatment.

What do others think?
Click to expand...

Nothing says you can't instruct your partner to pull over, lean patient back, put on pads, press charge (or press charge then put on pads, depends if your cardiac monitor will allow it), begin compressions, and press shock once charged...but to do two full minutes?

Primary VF responds very well to immediate defibrillation.
 
I believe you can shock if it is witnessed and can shock immediately . However, most cases people do not have a d fib right there so they are taught 5 rounds of CPR first. The CPR first is to prime the heart obviously. Why prime a primed heart?
Why would an EMT be arguing with their medic? I would say what I thought was correct and drop it. Let them research it
 
Do CPR long enough to charge the defib then shock. Personally, if I can get the pads on and shock with in ~45 sec I will just skip the CPR and save the patient the trauma. Coronary perfusion pressure wouldn't drop instantly (I don't think)

During various procedures (central line placement, cardiac Caths, etc) which frequently cause VT/VF we will have defib pads on and ready. If they sustain a lethal rhythm we charge and shock without CPR and the vast majority convert. If the first shock doesn't work we start CPR.


For what it's worth I also saw a Precordial thump work once :beerchug:
 
" For what it's worth I also saw a Precordial thump work once ".

Just to be a curmudgeon, prove it. ;)

Better yet, start a thread, see if others have also.
 
ROC PRIMED showed no significant difference between shocking right away versus shocking after a prescribed interval of CPR. However, compressions were almost certainly being performed while setting up the defib and charging the capacitor.

From: http://www.nhlbi.nih.gov/news/press-releases/supplement/questions-and-answers-roc-primed.html

"The preliminary results of the study indicate that a small amount of CPR (30-90 seconds) is just as effective as a longer period of CPR (approximately three minutes) before EMS providers analyze heart rhythm to determine the need for defibrillation when performing CPR. The method of analyzing heart rhythm after 30-90 seconds of CPR is just as beneficial as performing CPR for up to three minutes before analyzing heart rhythm. Both methods are in widespread use depending on the common practice of individual organizations."

We've measured this in-house and there was huge variability from shift-to-shift and crew to crew. Our top performers were shocking within about 1 minute from announcing "at patient". Since the correct compression rate is 100/min. you ought to be able to deliver about 100 compressions while the monitor is turned on, the pads are unwrapped, the cable is connected, the pads are attached to the chest, an energy level is selected, and the capacitor is charged.
 
mycrofft said:
" For what it's worth I also saw a Precordial thump work once ".

Just to be a curmudgeon, prove it. ;)

Better yet, start a thread, see if others have also.
Click to expand...

Seen it.

Why not just start CPR while monitor is hooked up? Most of the time our cycles aren't 2 exactly two minutes anyways. If the monitor's hooked up, patches on, I say shock 'em. Seen the cath lab do it plenty of times.
 
Remember I'm the guy who has said multiple times most CPR survivors didn't need it in the first place.:ph34r:
 
Analyze and pop them, and if that dosent work compress. I feel that of you waited to pop the pt you could go into asystoly. If you do get ROSC then start going down your list of causes and correct them due to the pt may go back into that bad arrythmia.
 
ACLS can use something more potent than an AED or defibrillator-only, too. Just saying.
 
HeatStroke said:
ACLS says witnessed arrests get defibrillated immediately
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Yes, as soon as you can get the pads on them. CPR for 30 seconds while you get the pads on will only help though, and practically will be the most likely situation you'll face.
 
Wheel said:
Yes, as soon as you can get the pads on them. CPR for 30 seconds while you get the pads on will only help though, and practically will be the most likely situation you'll face.
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This
+1

Follow the algorithm/protocol.
 
Wheel said:
Yes, as soon as you can get the pads on them. CPR for 30 seconds while you get the pads on will only help though, and practically will be the most likely situation you'll face.
Click to expand...

Pads?

What ever happened to paddles?
 
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