Pulseless VT/Accelerated idioventricular rhythm

[djthemac]

Merry Christmas Everyone!

I am hoping for some insight, forgive me if this is a stupid question.

Pretend you are working a code, and the presenting rhythm is VF, you administer 1 shock and 2 minutes of CPR, you do a rhythm check and find a wide complex, regular rhythm at a rate between 100-125 BPM, no pulse present. What is the next course of action? Shock?

My question can also be boiled down to, is there a rate component when determining shock-able VT, when in the pulsesless algorithm?

 

[Anjel]

If it's vtach without a pulse then yes I would shock. As long as it is greater that 100/min it can be vtach.

Shock, Epi or Amiodarone whatever is next on the list, CPR.

 

[NomadicMedic]

The current ACLS algorithm is to deliver a shock (to a shockable rhythm) every 2 minutes. At the 2 minute mark, you're ONLY shocking or not shocking. The drugs should be given during the 2 minutes of CPR, not at the 2 minute mark. I'm guessing this is simply an ACLS question, right?

 

[djthemac]

The current ACLS algorithm is to deliver a shock (to a shockable rhythm) every 2 minutes. At the 2 minute mark, you're ONLY shocking or not shocking. The drugs should be given during the 2 minutes of CPR, not at the 2 minute mark. I'm guessing this is simply an ACLS question, right?

Agreed on drug administration!

My question was more along the lines of shocking a slower ventricular tachycardia then what is typically presented during classroom megacodes. An atypically slow VT presentation if you will.

My thoughts are, if we shock tachyarrhythmias due to a decreased preload fill time and lack of atrial kick [in the case of VT] that is observed at higher heart rates, wouldn't a ventricular based rate around 100 give the heart enough time from a mechanical standpoint [assuming each QRS complex corresponds with musculature contraction] to provide some sort of measurable cardiac output? And if not, do we determine that rate to be above 100 BPM? i.e. we don't shock accelerated idoventricular (rate 80 BPM) not because its ventricular paced rhythm but because there is adequate preload fill time, and is therefore termed wide complex PEA.

 

[djthemac]

If it's vtach without a pulse then yes I would shock. As long as it is greater that 100/min it can be vtach.

Shock, Epi or Amiodarone whatever is next on the list, CPR.

thank you!

 

[NomadicMedic]

... Not to nitpick, but if there was a measurable cardiac output, there would be a palpable pulse, and you wouldn't be working an arrest... You'd be treating VT with a pulse.

The question specifically asked about pulseless wide complex tachycardia, which according to ACLS, calls for a shock.

 

[Aprz]

I think he may be suggesting that there is another cause for pulselessness other than the rhythm.

I'm not entirely sure if >100 means it's still ventricular tachycardia. I've read various minimums for ventricular tachycardia such as 120, 125, 130, and even 150. In one video, Amal Mattu said a rhythm couldn't be ventricular tachycardia because the rate was too slow <120.

Remember that ventricular tachycardia must have HR of at least 120.
Think of hyperkalemia when you have a wide complex, regular tachycardia with rates <120.

I believe the safest route would be to continue defibrillating the patient, but to continue looking for other causes of cardiac arrest such as hyperkalemia.

 

[VFlutter]

I would think idioventricular should be treated as PEA since under normal circumstances it "should" be a perusing rhythm. Idioventricular rhythms are common after cardiac reperfusion and we usually do not treat them. They rarely cause significant hemodynamic instability other than mild hypotension.

A possible scenario would be a patient having an MI who codes and sponteously reperfuses but still has a stunned myocardium that is not producing cardiac output even through conduction is restored.

 

[TomB]

I would continue CPR and give 1 mg Epinephrine and 1g/10 ml calcium gluconate. I would certainly not give an antiarrhythmic like amiodarone.

 

[NomadicMedic]

So Tom, you specifically wouldn't shock it?

 

[djthemac]

I think he may be suggesting that there is another cause for pulselessness other than the rhythm.

I'm not entirely sure if >100 means it's still ventricular tachycardia. I've read various minimums for ventricular tachycardia such as 120, 125, 130, and even 150. In one video, Amal Mattu said a rhythm couldn't be ventricular tachycardia because the rate was too slow <120.[/url]


I believe the safest route would be to continue defibrillating the patient, but to continue looking for other causes of cardiac arrest such as hyperkalemia.

Thank you for clarifying. This is my point exact. I dont know if a rate of around 100 is fast enough to cause a severe decrease in cardiac output to the point of pulselessness by itself.

It seems the general consensus is that a pulseless wide complex rhythm above 100 BPM should be defibrillated.

 

[Anjel]

Thank you for clarifying. This is my point exact. I dont know if a rate of around 100 is fast enough to cause a severe decrease in cardiac output to the point of pulselessness by itself.

It seems the general consensus is that a pulseless wide complex rhythm above 100 BPM should be defibrillated.

There is usually some other cause for the arrest that resulted in the pulse less vtach. The scenario you gave the pt was at first in Vfib which has a million things that can cause it.

The pt could of been in vtach with a pulse that turned into Vfib, and after a shock went back to vtach. Which is promising.

 

[TomB]

So Tom, you specifically wouldn't shock it?

I would not.

 

[jefftherealmccoy]

This brings an interesting question to my mind. If a pt is in a pulseless rhythm and converts into V tach with a pulse, what then would you do? I've been told by many of the older medics I work with you then do nothing unless they loose a pulse. A profusing rhythm with a blood pressure should not be touched, even if it's V tach, when converted from a pulseless rhythm. They're logic is progression is progression and nothing should be done for fear of an intervention causing the rhythm to change for the worse.

All the stuff we did in mega codes in school you would've shocked it or pushed amiodarone until you got NSR.

 

[chaz90]

This brings an interesting question to my mind. If a pt is in a pulseless rhythm and converts into V tach with a pulse, what then would you do? I've been told by many of the older medics I work with you then do nothing unless they loose a pulse. A profusing rhythm with a blood pressure should not be touched, even if it's V tach, when converted from a pulseless rhythm. They're logic is progression is progression and nothing should be done for fear of an intervention causing the rhythm to change for the worse.

All the stuff we did in mega codes in school you would've shocked it or pushed amiodarone until you got NSR.

Assuming the initially presenting pulseless rhythm was V-Fib or V-Tach, I'd be hanging an Amiodarone drip after ROSC if I hadn't already administered both during the code itself. Dependent on the BP and rate of the pulsatile V tach, I definitely wouldn't be attempting cardioversion of a perfusing rhythm post cardiac arrest.

 

[teedubbyaw]

I would continue CPR and give 1 mg Epinephrine and 1g/10 ml calcium gluconate. I would certainly not give an antiarrhythmic like amiodarone.

And why wouldn't you give amiodarone?

 

[zzyzx]

I don't think you're going to get a definitive answer to your question because there isn't one. You have to accept that in codes there is often going to be some uncertainty.

A wide-complex tachycardia with a rate of 120? It's probably not Vtach, but it could be. There's no harm in simply treating it as PEA and continuing CPR. Recheck it in a minute or two and it's quite likely you will see a different rhythm, hopefully one that will be easier to call.

 

[TomB]

And why wouldn't you give amiodarone?

Because I prefer a wide complex rhythm at a rate of 100 to asystole. I'm actually breaking one of my own rules here. I normally don't theorize about an ECG I haven't laid eyes on. But, there's no way I would give amiodarone in this set of circumstances. Consider the Hs and Ts. I would only consider amiodarone for refractory VF/VT (in the latter case with a rate > 120 and probably > 150).

 

[teedubbyaw]

Gotcha. Good info.