SVT vs. V-tach

[medic417]

Why should it delay the patient's care? For unstable patient, the therapy is identical. If the patient is hemodynamically stable, then I would rather the treating paramedic show restraint. A delay in care is far superior to a clinical misadventure -- the kind the patient suffers when VT is misclassified as SVT with aberrant conduction.


I'd like to see you back that up with peer reviewed literature. Even if it were true (which I doubt) the failure to rule in VT does not rule out VT, and that is the pointed issue.

The delay is deciding where to take them or even on not doing anything when you should do something.

As to the research contact Bob Page at St Johns for that.

Yes you can still have VT w/o it showing but in most cases it is there.

 

[boingo]

Tom's point is that if they are sick, they get cardioversion, regardless of point of origin, if not, a "drug free" approach may be the safest for the patient. Tom being a firefighter knows the drug box is bad! Just kidding....

I'm not sure why a patient with VT would be taken to a seperate hospital than one with SVT, so don't know why the actual dx would factor into that.

One can mentally masturbate the nuances of VT v.s. SVT, however if ANY doubt, one must tx as VT until proven otherwise. There are plenty of examples of EKG's meeting criteria, brugada's, Marriots, etc...that don't appear to be VT but in fact are. First do no harm.

 

[TomB]

Tom's point is that if they are sick, they get cardioversion, regardless of point of origin, if not, a "drug free" approach may be the safest for the patient. Tom being a firefighter knows the drug box is bad! Just kidding....

I'm not sure why a patient with VT would be taken to a seperate hospital than one with SVT, so don't know why the actual dx would factor into that.

One can mentally masturbate the nuances of VT v.s. SVT, however if ANY doubt, one must tx as VT until proven otherwise. There are plenty of examples of EKG's meeting criteria, brugada's, Marriots, etc...that don't appear to be VT but in fact are. First do no harm.

Hahaha!

Mongo like drug box!

 

[emtbill]

None of the services I have ever worked at have carried cardizem for (what I suspect are) these very reasons (misdiagnosing wide complex as SVT). We have metoprolol for SVT's unresponsive to adenosine. What do the veterans here think about giving adenosine to a wide complex tachycardia that is suspected of being SVT (using whatever algorithm you choose)? If it's an aberrantly conducted reentrant SVT this should fix it, otherwise you may be able to see atrial fib or flutter waves. Adenosine should not make VT worse right? What about sedating and cardioverting every wide complex tachycardia to avoid having to give these cardiotoxins all together?

@medic417: I also took Page's seminar and learned the same criteria you mentioned. I don't know about in your class, but with mine he never once talked about SVT. He only talked about how to rule in VT. He also did not talk about therapy to consider when his VT criteria failed, suggesting SVT. Well...if memory serves I think he talked about a tachycardia that failed his criteria for VT, the medic gave adenosine, saw it was AF, then gave cardizem with successful conversion, but largely Page doesn't advocate giving CCB's to a wide complex tachycardia...maybe he's worried about being liable if a bunch of people start killing patients in VT with cardizem after taking his class .

@Tom: are you suggesting taking all stable patients with wide complex tachycardias to the ER and not giving drugs, or just the ones that might be in SVT, while still giving drugs to a suspected stable VT?

 

[medic417]

Better to leave the drugs in the drug box altogether! Having said that, lidocaine and adenosine used to both be a part of the "wide complex tachycardia of uncertain etiology" algorithm in the AHA ECC guidelines. There are much worse drugs you could try (a calcium channel blocker for example). However, none of these drugs are currently indicated. What's the rush? If it's unstable, cardiovert. If it's stable, consider capturing a 12 lead ECG, starting an IV, providing supportive care, and taking the patient to the hospital, especially if there's anything particularly disturbing about it (irregular, polymorphic, or extremely fast rate).

If we have whats needed in the field to start treatment prior to transport patient benefits as ever second heart cells are dieing.

Also note on 96% diagnostic of VT, in other words if my method shows VT odds are it is VT. There are other methods that have proven much less reliable yet patients are being treated by them.

 

[TomB]

If we have whats needed in the field to start treatment prior to transport patient benefits as ever second heart cells are dieing.

Also note on 96% diagnostic of VT, in other words if my method shows VT odds are it is VT. There are other methods that have proven much less reliable yet patients are being treated by them.

I wouldn't criticize you for giving 150 mg amiodarone over 10 minutes, but generally speaking, if the heart is experiencing demand side ischemia to the point of myocardial damage there will be symptoms like CP and SOB.

 

[TomB]

Billy -

I'm saying that a perfusing rhythm is a good thing. If you consider you Hs and Ts, correct hypoxia, acidosis, hypovolemia, electolyte derangement, and you make the reasoned clinical decision to try an indicated antiarrythmic, then go for it. Just realize it's a big responsibility and any antiarrythmic can be proarrhythmic. I just get nervous when I see discussion about using morphology to rule out VT. It's dangerous.

Tom

 

[medic417]

Billy -

I'm saying that a perfusing rhythm is a good thing. If you consider you Hs and Ts, correct hypoxia, acidosis, hypovolemia, electolyte derangement, and you make the reasoned clinical decision to try an indicated antiarrythmic, then go for it. Just realize it's a big responsibility and any antiarrythmic can be proarrhythmic. I just get nervous when I see discussion about using morphology to rule out VT. It's dangerous.

Tom

Not rule out rule in. If I said rule out I apologize. Because if I rule it to be VT I will have treatment options that differ from SVT.

Since I may have confused someone let me clarify you can not rule out anything with an EKG alone.

I do feel it is important that we start treatment in the field rather than waiting for the hospital as there are often long delays there. So an extra 5 minutes on scene getting treatment started may actually save 30 minutes or more of cardiac tissue when you factor in the waits at the ER.

 

[Akulahawk]

None of the services I have ever worked at have carried cardizem for (what I suspect are) these very reasons (misdiagnosing wide complex as SVT). We have metoprolol for SVT's unresponsive to adenosine. What do the veterans here think about giving adenosine to a wide complex tachycardia that is suspected of being SVT (using whatever algorithm you choose)? If it's an aberrantly conducted reentrant SVT this should fix it, otherwise you may be able to see atrial fib or flutter waves. Adenosine should not make VT worse right? What about sedating and cardioverting every wide complex tachycardia to avoid having to give these cardiotoxins all together?

@medic417: I also took Page's seminar and learned the same criteria you mentioned. I don't know about in your class, but with mine he never once talked about SVT. He only talked about how to rule in VT. He also did not talk about therapy to consider when his VT criteria failed, suggesting SVT. Well...if memory serves I think he talked about a tachycardia that failed his criteria for VT, the medic gave adenosine, saw it was AF, then gave cardizem with successful conversion, but largely Page doesn't advocate giving CCB's to a wide complex tachycardia...maybe he's worried about being liable if a bunch of people start killing patients in VT with cardizem after taking his class .

@Tom: are you suggesting taking all stable patients with wide complex tachycardias to the ER and not giving drugs, or just the ones that might be in SVT, while still giving drugs to a suspected stable VT?

Sacramento doesn't use adenosine, Cardizem, or metopralol for tachycardias. If they're stable, they get watched. If the patient becomes unstable, we sedate (if necessary) and Sync Cardiovert. For Wide Complex Tachycardias, regardless of etiology, after 4 shocks, we begin using Lidocaine. If they go into cardiac arrest, we switch protocols and treat that rhythm instead.

Is this ideal? Not for most places. However, here, most of the time, if you've begun transport early, you're not likely to reach the end of the protocol before you reach the emergency room, unless you're starting from way out along the eastern or very southern portions of the County.

Other Counties I've worked in use adenosine, but for unstable tachycardias, they go straight to cardioversion. Consider this: if you're having to give amiodarne (Cordorone) over 10 minutes, chances are your patient is not exactly emergently unstable. Adenosine, if you have it handy, works. Cardizem and metopralol also work... but you've got a patient who's got pulses and isn't so unstable that you need to go straight to electrical therapy.

Personally, I'd like to have the tools to use those other medications for chemical cardioversion... but that's not an option here.