treating tachy rhythms

[noobmedic]

hey everyone. when do you treat tachy rhythms (svt, vtach). obviously you'd treat one of these rhythms if someone's complaining of cp, sob, decreased loc, poor skins, etc with drugs or cardioversion. rather my question is when the person seems stable.

for example, if someone's complaining of being lightheaded or minor cp or minor sob and you're looking at svt, but they have a good b/p (>110 sys) and good skins and they don't respond to o2, fluid, vagal manuveurs) would you treat with adenosine or would you transport and make bh contact?

in class we were taught to treat vtach. if they're unstable you cardiovert. if they're stable lido or amio.

my question is basically, as an als provider where do you draw the line to treat or not treat? i know people don't just walk around with svt and in a nearby county they're allowed to treat it if they see it without bh contact, other places have to make to contact before treating for stable pts.

btw, when i say vtach, i mean vtach with a pulse.
thanks!

 

[truetiger]

In the scenario you described I would give the adenosine, if no change I would follow my protocols and administer diltiazem. If the cardizem doesnt do the trick and the patient is still stable I would make contact with med control and advise them of the situation if I haven't done so already. I would not hesitate at all to cardiovert if the patient became hemodynamically unstable.

 

[Melbourne MICA]

It's how you say it

Now this may be a matter of semantics to some but for many others, myself included, the term "stable" is an expression that a:- should never be attached to a lethal arrhythmia - VT being one of those, and b: - should never be attached to the perfusion state of a patient in VT either. The terms are anachronistic to the whole scenario of a patient presenting in VT. VT is never stable - and yes we have all heard the stories about the patient who had VT for hours - I've seen it myself. This is simply an individual patient event in which the deterioration (including onset of symptomology) accompanying VT has a different time frame to others. In the case of perfusion "stable" perfusion should be looked at similarly and much more accurately referred to as adequate, borderline or inadequate - once again because the maintenance of an adequate perfusion state in the VT patient is also an individual event.

Semantics is a concern when it implies, describes or worse, encourages, a misleading perception. And ambulance is full of misleading perceptions that ultimately, and far too often, encourage bad habits or even change practice for the worse.

Finally - another way to look at this idea is check out the latest theories on the formation of both VT and VF.

Both are now theorised to revolve around (forgive the wordplay) re-entry circuit phenomenon. VT being a local or small regional issue in the left ventricle whilst VF is believed to occur as a cascade of multiple re-entry circuits that self-perpetuate.

- A bit like a snowball running downhill.- You don't know if its going to pick up speed, what direction it will travel and where and when it will finish. If we can trap the snowball before it gains impetus and momentum the phenomenon may be slowed or will be stopped altogether. So your treatment (eg amiodarone) is best applied whilst there is some resistance (perfusion) left at the top of the hill and before the snwoball gets too big.

But its dangerous standing out there on the slope with that growing snowball coming at you and you may make things worse (Amio has side effects eg) or not stop it all. If you can't slow it or stop it you have an avalanche and it will overwhelm any resistance against it. So you set off explosives to take the sting out of the avalanche (synch-cardiovert) if everything else fails.

The argument now is whether its better to set off the explosives early on before the snowball even starts to pick up pace because trying to catch the snowball when it changes its path doesn't always work.

So next time you see VT - think snowballs. That's enough for me. Someone else can deal with SVT. Now that's another story again.

Cheers

MM

 

[RatMed]

In Poland we're not allowed to perform cardioversion without a doctor's direct supervision so in the field we're limited to antiarrythmics: amiodaron and lidocaine.
I've been lucky enough to only encounter SVT and fast AF patients in relatively good condition (still would qualify as unstable in my textbooks) and decided to use amiodarone several times on longer transports. Wouldn't say it worked wonders but it worked every time: HR would drop, BP raise, most symptoms would diminish.
I've never observed the dreaded BP drop after amiodarone. From what I read it shouldn't happen if it's infused in indicated 10-15 minutes time. I think, most drugs used to sedate the patient prior to synch cardioversion cause serious side effects more likely. But then again, we're limited to benzos and morphine.
From what I seen, the ED docs where I work also prefer drugs over cardioversion as long as patients condition permits it.
Vagal maneuvers never seem to work for me.

Sorry for my English.

 

[vquintessence]

It's not so much a matter of when or when not to treat, but how judiciously to go about it. Obviously a case by case basis exists, and that's when a clinician comes into play (opposed to a jockey who's just in it to win the race).

Post syncopal, 26 y/o in "svt" at 240's.

Somnolent 34 y/o has been working strenously in a physically demanding climate. The monitor shows "svt" at 150's.

78 y/o with hx of Pagets disease (primarily affecting the thorax & clavicles) is complaining of a vague chest discomfort. ekg shows svt at 170's.


Those are all deliberately vague scenarios, but I assure you there is more to them than "to give or not give adenosine". Would you need more information to come to any treatment pathways, or are you in it to win the race?

 

[MrBrown]

Basically you treat a rhythm with cardiovascular compromise; compromise is not defined in our Procedures but it means more than a bit of chest tightness or shortness of breath.

We use amiodarone as our first treatment of choice except for VT, VT we cardiovert.

 

[18G]

There really isn't a defining line that tells you when to skip pharmacological intervention and go straight to cardioversion. Most commonly though if the patient is sob, dizzy, has chest tightness, still perfusing adequately without too much compromise, and is conscious and alert, medications are inline.

If the patient has an altered mental status, is hypotensive, chest pain, pulmonary edema, etc then cardioversion is inline.

Again, the lines that distinguish become blurred in many patients so as others said, clinical judgement. Cardioversion is advocated to be a very safe intervention and method for rhythm conversion.

Most say if unsure, cardiovert.

 

[sihi]

In SVT with BP 90 I have used Adenosine.

Tachyarhytmias wit BP lower then 90 - shock condition I would try to do sedation and sync. cardioversion.

Stable AF we treat with Amiodarone, Propafenon, or frequency control by Metoprolol or Digoxine.
Tachycardic AF with cardial insuff. and hypotension >90 without coronary syndrome I would treat with Digoxine.

Sync. cardioversion I would do in patient with BP <90 and if tachyarrhitmia complicated with pulmonary oedema.

Sedation would do using Midazolam. After Midazolam patient do not remember nothing - amnesia, so narcotic analgetic (increase hypotension) is not needed.

Some our EM phisicians and anestesiologists use Propofol for sedation, that is not the best for hypotensive patient.

 

[Akulahawk]

Something else to consider: if you have time to "snow" the patient before electrical cardioversion, you probably have time to consider attempting cardioversion via meds first...

Also consider the overall status. Sometimes the best medicine is to sit, chat, and transport and do some "housekeeping" stuff en-route.