Adult Tachycardia with a Pulse

Question 1

What your underlying goal with any ACLS situation?

Answer 1

Identify and Treat underlying causes:
- 5 H’s and 5 T’s, even if not cardiac arrest. So order a slew of labs.
- Supp O2 if hypoxemic
- Monitor vitals and often get a 12-lead EKG
- Often obtaining further IV/arterial/central access, and may place advanced airway if not in place
- Often would consult cardiology

Question 2

How fast of a HR to make you suspect a tachyarrhythmia vs just Sinus Tach?

Answer 2

≥ 150 bpm

Question 3

Two main successive branch points in Adult Tachycardia with a Pulse algorithm (ie, what two things, in order, do you ask yourself as you go down the algorithm to select the correct treatment)?

Answer 3

1) Hemodynamically UNstable?
- If yes pt is unstable, the answer is synchronized cardioversion (except if it is regular and narrow, in which you’d consider adenosine). Really take this in - any UNstable tachycardia WITH A PULSE - whether regular or irregular, wide or narrow QRS complex, or monomorphic or polymorphic QRS - gets a SYNCHRONIZED cardioversion.
- The only sort of exception for a tachycardia with a pulse that would get an UNsynchronized shock/defibrillation instead of a Synchronized cardioversion is an UNstable, WIDE QRS complex, POLYmorphic tachycardia, since it’s likely polymorphic VT and is probably just about to spiral into a VF or a pulseless VT, which is a cardiac arrest, which would be treated with an UNsynchronized defibrillation.

2) Pt is hemodynamically stable (HDS), but is the QRS WIDE?
- If QRS is WIDE, the answer is an antiarrhythmic infusion, or if refractory to antiarrhythmic infusion you’d cardiovert vs. shock/defibrillate (except if the wide QRS rhythm is clearly regular and monomorphic so you’re positive it is SVT with aberrancy [ie, SVT with a BBB], in which you’d consider adenosine)
- If QRS is NARROW, it’s AV node inhibition (Vagal maneuvers or adenosine) to diagnose or treat it, or Rate control (CCB or BB), and maybe Amio depending if regular or irregular.
- Regular vs Irregular R-R is the third branch point on a different card

Question 4

3rd branch point to consider in adult Tachycardia with a Pulse algorithm to consider every time

Answer 4

Regular vs Irregular rhythms. Applies to narrow AND wide QRS tachyarrhythmia branches

Question 5

S/S of a hemodynamically UNstable tachyarrhythmia?

Answer 5

Persistent Tachyarrhythmia causing:
1) HoTN
2) AMS
3) S/S of Shock
4) ACS (ischemic chest pain, EKG s/s)
5) Acute CHF

Question 6

Standard Tx of hemodynamically UNstable Tachyarrhythmia?

Answer 6

Synchronized Cardioversion. Treat unstable SVT with immediate synchronized cardioversion, except in one specific instance may try something else (different card)

Question 7

If a hemodynamically UNstable tachyarrhythmia is refractory to a synchronized cardioversion, what are your next tx options?

Answer 7

1) Increase energy level of next cardioversion
2) Add an anti-arrhythmic infusion
3) As always, work up underlying causes (5 H’s and T’s, etc.) and probably seek expert consultation in the form of consulting cardiology

Question 8

Synchronized Cardioversion - what are the Biphasic doses based on tachyarrhythmia tele tracing:

Answer 8

Narrow complex and regular (regular SVT): 50-100 J
Narrow complex and irregular (irregular SVT, eg Afib): 120-200J
Wide complex and regular: 100J
Wide complex and Irregular: Shock / Defibrillate / UNsynchronized at 200J

Giselle says they just use a high dose the first time for any cardioversion, maybe even the max dose possible on the defibrillator

Question 9

Unstable tachyarrhythmia but the rhythm is regular and narrow (so a regular SVT) - what options for treatment

Answer 9

Synchronized cardioversion is always an option

Adenosine is the other option. This is the ONLY UNTABLE tachycardia (regular and narrow = SVT) in which Adenosine may be considered. NO other UNstable arrhythmias, including REGULAR and MONOMORPHIC VT, may be treated with adenosine! It’s only STABLE regular & monomorphic VT that may be treated with adenosine

Question 10

What are the three types of tachyarrhythmias in which you may consider Adenosine? Rate and Rhythm characteristics to consider:
1) Hemodynamic Stability (stable vs UNstable)
2) Width of QRS (wide or narrow)
3) Overall Rhythm (Regular or Irregular)
4) QRS morphology (Monomorphic or Polymorphic) - only even mention if QRS is WIDE

Answer 10

REGULAR, NARROW complex tachycardia (regular SVT) when the patient is STABLE - this is the main category

REGULAR, NARROW complex tachycardia (regular SVT) when patient is UNstable

REGULAR, WIDE complex, MONOMORPHIC tachycardia (this is SVT with aberrancy [ie, SVT with a BBB]) when the patient is STABLE. However, this is hard to distinguish from just VT, and AMIO treats both SVT with aberrancy and VT, so just give amio!

Question 11

For the most part, what two to four types of tachyarrhythmias are you really thinking about treating when you’re considering treating with Adenosine?

Answer 11

1) AVRT or AVNRT - adenosine is THERAPEUTIC
2) A-flutter - adenosine is DIAGNOSTIC
- big note: both of these are hemodynamically STABLE, NARROW complex, REGULAR tachycardias!

If the rhythm is hemodynamically STABLE, NARROW complex, BUT IRREGULAR, then it’s probably A-fib, and Adenosine doesn’t treat that so don’t give it!

The last two situations where Adenosine are applicable are definitely more rare but worth mentioning for completeness sake:
3) pt is hemodynamically UNstable, but the rhythm is for sure NARROW and REGULAR. Here the patient is lucky enough that you can try Adenosine first before a cardioversion
4) SVT with Aberrancy (an SVT with a BBB, so a WIDE complex QRS). This is hard to tell apart from VT, and amio treats both of them anyways, so just give Amio.

Simply think of the MOA of adenosine to remember what types of tachyarrhythmias it’s useful or pointless for: Adenosine’s MOA is to completely block conduction at the AV node! So it may be useFULL for tachycardias that begin ABOVE the AV node (eg, Aflutter, AVRT, AVNRT, and regular monomorphic wide-complex tachycardia that you suspect is SVT with aberrancy [aberrancy = BBB]), but will be useLESS for arrhythmias that start BELOW the AV node (which is basically any WIDE complex tachycardia, regular or irregular, other than SVT with aberrancy)

Question 12

Benefit of Adenosine in a few types of HDS, narrow, regular tachycardia?

Answer 12

AVRT (one pathway involves AV node) or AVNRT (obvi involves the node): can be curative since adenosine blocks the AV node

A-flutter: blocks any atrial flutter waves from getting through AV node into a ventricular depolarization, so you see just the flutter waves. It’s DIAGNOSTIC for Aflutter, not therapeutic.

Question 13

Adenosine dose for any type of tachycardia you’re using it for

Answer 13

6mg IV push and MUST FLUSH. Central access is definitely best
12mg IV push second dose

It just stops AV nodal conduction for like 12 seconds and patients are going to feel weird/bad. Then they come back.

Question 14

What is the definition of a “wide complex” QRS

Answer 14

≥ 0.12 sec

Question 15

Pt is hemodynamically STABLE, but the QRS is wide. What is the treatment?

Answer 15

1) Adenosine only if regular and monomorphic (so an SVT with a BBB causing a wide QRS). But this is hard to tell apart from stable VT, so just give AMIO since it treats both
2) Anti-arrhythmic infusion - Amio, Procainamide, or Sotalol.

Question 16

Is Adenosine ok for someone with WPW (delta wave) and/or Asthma?

Answer 16

NO, it is not. It’s especially not ok if there is Afib + WPW.

WPW (Wolf-Parkinson White) is a specific form of AVRT. AVRT, WPW, and pre-excitation syndromes are all pretty similar terms. WPW has an accessory conduction pathway (ie, bundle of Kent) that bypasses AV node. The delta wave is an upsloping of the QRS initial upward part, but usually doesn’t widen the QRS enough to be a wide QRS.

It’s beyond my understanding, but somehow having an intact AV node prevents a WPW + afib patient from having the really fast afib atrial rates travel unopposed to the ventricles, which would otherwise degenerate into VF. Since Afib is sort of the deadliest part of this (the super fast rates), ANY TIME YOU SEE AN IRREGULAR TACHYCARDIA (whether narrow or wide), YOU SHOULD AVOID ADENOSINE!! Adenosine doesn’t treat Afib anyways, but it’s even worse than being ineffective - it could be deadly!

Quick note on treating SVT with aberrancy with Adenosine. “Aberrancy” is just a BBB, which causes a wide-complex QRS. Adenosine is fine for wide-complex arrhythmias, as long as it’s not irregular (ie, as long as there’s no Afib) and as long as it’s STABLE. That being said, SVT with aberrancy is difficult to distinguish from VT, and amiodarone is a fine treatment for either, so just give Amio!

Question 17

Aflutter Treatments

Answer 17

1) Adenosine - diagnostic, NOT therapeutic. so NOT a treatment
2) Beta-blockers - slows it down which can be good, but wouldn’t do if it was UNSTABLE A-flutter (easy to remember since should always cardiovert in ACLS if unstable tachycardia)
3) Anti-arrhythmic to convert it (eg, Amio) - but Aflutter is pretty resistant to chemical conversion
4) Synchronized cardioversion - yes works, happens all the time

Question 18

Hemodynamically stable, narrow QRS complex, REGULAR tachycardia - broad categories of treatment

Answer 18

AV node inhibition:
1) Vagal maneuvers (bare down, blow into syringe, cold water to face) - vagus-mediated AV node inhibition to break the SVT, or at least diagnose it
2) Adenosine - AV node inhibition

Rate control - probably try this second if Adenosine or vagal maneuvers failed to convert tachyarrhythmia:
1) BB’s - rate control. Less negative inotropy
2) CCB’s - rate control. More negative inotropy so worse with unstable pts

Question 19

Hemodynamically stable, narrow QRS complex, IRREGULAR tachycardia - broad categories of treatment

Answer 19

Rate Control:
1) BB’s - rate control. Less negative inotropy
2) CCB’s - rate control. More negative inotropy so worse with unstable pts

Rhythm Control:
1) Amiodarone

Question 20

Vagal maneuvers - method and MOA

Answer 20

Bear down, or blow through a straw or syringe. Stimulates vagus which inhibits AV node

Question 21

Vagal maneuvers - which tachyarrhythmias does it treat?

Answer 21

Stable, narrow complex, regular tachycardia

More specifically, it treats SUPRAcentricular (starting above the ventricles) tachycardia that then travel THROUGH THE AV NODE to the ventricles. The AV node being blocked by CN X is the MOA of tachycardia ablation here.

Question 22

Beta Blockers - list the common ones for tachyarrhythmias

Answer 22

For stable, narrow, regular tachycardia
For stable, narrow, irregular tachycardia

1) Esmolol
2) Metoprolol

consider AVOIDING BB’s in ASTHMA (block the beta receptors in lungs which can cause bronchospasm; opposite of the beta-agonist albuterol)

Question 23

Esmolol - dose, and when to give

Answer 23

For stable, narrow, regular tachycardia
For stable, narrow, irregular tachycardia

0.5 mg/kg over 1min. May repeat. May start infusion at 50 mcg/kg/min

Question 24

Metoprolol - dose, and when to give

Answer 24

For stable, narrow, regular tachycardia
For stable, narrow, irregular tachycardia

1-2.5mg IV. Repeat or double the dose after 2.5min

Question 25

Calcium Channel Blockers - list the common ones for tachyarrhythmias

Answer 25

For stable, narrow, regular tachycardia
For stable, narrow, irregular tachycardia

1) Diltiazem

Question 26

Diltiazem - dose, and when to give

Answer 26

For stable, narrow, regular tachycardia
For stable, narrow, irregular tachycardia

5-10 mg IV over 2 min. May repeat after 5 min

Question 27

Which Antiarrhythmic agent for hemodynamically stable, narrow QRS complex, irregular tachycardia

What is this agent’s dosing guidelines?

Answer 27

Amiodarone

150mg slow IV infusion. may repeat once. then start infusion at 1mg/min for first 6 hours.

Question 28

Hemodynamically stable, wide QRS complex, Regular tachycardia
- General explanation of this tachycardia
- Broad Treatment categories

Answer 28

If a stable, wide-QRS complex tachycardia is REGULAR, then it’s likely also MONOMORPHIC. So it’s likely a monomorphic VT. However, it could just be an SVT with aberrancy (ie, an SVT with a BBB such that the QRS is widened but still regular).

Broad treatment categories for treatment of hemodynamically stable, wide QRS, regular tachycardia:
1) Adenosine (6 then 12mg) if you’re sure it’s SVT with aberrancy
2) Antiarrhythmic if uncertain VT versus SVT with aberrancy: Amio, Procainamide, or Sotalol. As I’ve said previously, SVT with aberrancy is difficult to distinguish from VT, and amiodarone is a fine treatment for either, so just give Amio!

Question 29

What rhythm is likely causing the rare hemodynamically stable, wide QRS complex, irregular tachycardia?

Answer 29

It’s likely polymorphic VT. Like I said previously, if the QRS is polymorphic, I think it’s pretty likely that your rhythm will be irregular.

Giselle said it’s basically not a thing that you’d somehow be stable if you were in polymorphic VT. If you see a good rhythm pop into polymorphic VT, you’re immediately thinking about getting pads on for immediate DEFIBRILLATION - that is, and UNsynchronized SHOCK)

If there’s wide complex, irregular (likely also polymorphic QRS), hemodynamically UNstable VT, thte treatment is most definitely immediate UNsynchronized defibrillation.

New notes: I think the other think it could be is probably WPW with abherency + Afib (other words for WPW are AVRT and Pre-excitation syndrome). In this case, I guess you could think about PROCAINAMIDE if it’s somehow STABLE, but I think this would very likely be unstable, and I think you’d be giving a ?Synchronized? Cardioversion?

Question 30

Amiodarone - dose, and when to give

Answer 30

150mg slowly over 10 min. may repeat once. then 1mg/min for first 6 hours

Treats:
- Hemodynamically stable, narrow QRS, irregular tachycardia
- Hemodynamically stable, wide QRS, regular tachycardia (QRS is probably also monomorphic if it’s regular and stable). Works for both SVT with aberrancy (SVT with a BBB so a wide QRS) and monomorphic VT

Amiodarone prolongs the QT. Don’t give in Torsades (defined as Polymorphic VT with prolonged QT) or other instances where QT is long (like > 600msec)

Question 31

Procainamide - dose, and when to give

Answer 31

20-50 mg/min until arrhythmia is suppressed, hypotension ensues, QRS duration increases > 50%, or maximum dose of 17mg/kg is given (~1200 mg for a 70kg person). Avoid if prolonged QT or CHF.

Hemodynamically stable, wide QRS, regular tachycardia (QRS is probably also monomorphic if it’s regular and stable)

Question 32

Sotalol - dose, and when to give

Answer 32

100mg (1.5mg/kg) over 5 min. Avoid if prolonged QT or CHF.

Hemodynamically stable, wide QRS, regular tachycardia (QRS is probably also monomorphic if it’s regular and stable)