Cardizem Vs. Adenosine in SVT

[ExpatMedic0]

Did you chase it with a pressure bag or something? That's pretty impressive!

You win a cookie

J/K

I arrived second on scene. EMT's where already there, one was an Intermediate who had started this 22G on the hand and the lady was a hard stick. I had one of the EMT's hold a pre-filled saline syringe while I slammed the Adenosine as hard and fast as I could then grabbed the saline and slammed it with all my might, immediately lifting the patients arm in the air afterward and hoped gravity would lend a hand also.
It took a couple seconds longer than usual (it seemed like) but it worked. I captured a beautiful before, during, and after rythem strip. I was showing it off all day.

 

[Christopher]

have any of you had issues with heart pauses that...don't restart..with adeonsine. I know its standard procedure to have the crash cart right next to the patient when pushing adenosine. I am not sure how prevalent it is for the patient to require a shock after pushing adenosine. I would think this would be considered a fairly detrimental side effect if it happens even infrequently.

If by "don't restart" you mean asystole, then yes, there are numerous case reports of prolonged asystolic pauses after adenosine administration. Most of these happen to be when given through a central line and they forget to halve the dose. I've not seen pauses greater than 2-3 seconds in the field or ED with adenosine.

Longest pause I've seen was actually post-cardioversion of symptomatic atrial flutter in the ID with ~8 second pause. The cardiologist was unimpressed while our heart rates doubled to compensate for our patient's asystole.

If by "don't restart" you mean ventricular fibrillation, then yes, there are also cases of adenosine's proarrhythmic nature causing VF. Although, often these have an aspect of polypharmacy or inappropriate administration (e.g. Afib+WPW receiving adenosine).

Verapamil has a ton of case reports of both bradyarrhythmias, hypotensive events, and ventricular proarrhythmias. Diltiazem has less, but they're still present.

Our ED brings the crash cart on any patient receiving a bolus antiarrhythmic, conscious sedation, or cardioversion. Proper preparation prevents piss poor performance.

 

[Christopher]

So, given the option of adenosine or cardizem in a patient with SVT that is seemingly stable SVT 180-220, BP 110/75, o2% is fine and PT looks okay, what do you go with with on the rig?

My decision is partially patient presentation and partially rhythm interpretation. Our area is unforgiving to paramedics who defer Rx when they're more than capable and equipped to do it, unless the situation truly requires you to take it slow.

Basically, stable SVT of suspected reentry will get adenosine from me.

Stable SVT of suspected automatic focus will get cardizem or procainamide, or metoprolol, depending again on my rhythm interpretation and DDx. As I use a more traditional definition of SVT, SVT with automatic focus includes AF, AT/Aflut, EAT w/ block, and JT.

I'm more likely to let a patient "ride" with EAT (we have a kid in our first due with EAT, multiple ablations w/o help) or a more controlled AF/AFlut.

does transport time factor into your decision?

Not really, unless I'm close to the hospital and feel the patient needs more "eyes" or we need more capability; I'll probably treat in the field. Usually where I find them.

Does your decision change in the ER setting?

I've never worked more than extra-hands shifts in the ED, so I would imagine my options would be dictated by the ED MD or a cardiology consult. However, I only see cards in the house when its pacemaker related or going to be a electrical cardioversion.

 

[FLdoc2011]

Just had a recent case here.... guy previously in NSR went into an irregular wide complex tachycardia. Hemodynamically stable, felt a little "funny" and uncomfortable but otherwise stable. HR sustained at least 160-180's with couple bursts up to low 200's.

We knew his detailed history which guided our therapy but would have happened in a prehospital setting with this gentlemen with an irreg wide complex tachyarrhythmia?

 

[Christopher]

Just had a recent case here.... guy previously in NSR went into an irregular wide complex tachycardia. Hemodynamically stable, felt a little "funny" and uncomfortable but otherwise stable. HR sustained at least 160-180's with couple bursts up to low 200's.

We knew his detailed history which guided our therapy but would have happened in a prehospital setting with this gentlemen with an irreg wide complex tachyarrhythmia?

Procainamide is purpose built for that exact situation (and elective cardioversion). Depending on the shortest R-R I've been comfortable with cardizem in AF w/ RVR and wide complexes, but I generally steer pretty clear without a convincing history of AF w/ RVR episodes.

 

[FLdoc2011]

Thought process change any if the patient has a known bypass tract/WPW?

 

[Christopher]

Thought process change any if the patient has a known bypass tract/WPW?

Procainamide is your "safe" choice, but in known bypass tract I'm inclined to cardiovert.