ACLS - Tachycardia Flashcards
When tachycardia is the cause of signs/symptoms, the heart rate is generally
greater than _____
150 bpm
If a symptomatic tachycardia exists clinically we see this triad:
○ Rapid heart rate is present
○ The patient has symptoms
○ The symptoms are due to the rapid heart rate (more likely at >150 bpm)
Tachycardia symptoms
● Chest discomfort or pain, ischemic
● Shortness of breath
● Altered mental status
● Weakness/Fatigue
● Lightheadedness/Dizziness
● Presyncope
Tachycardia Signs
● Hypotension
● Orthostatic hypotension
● Pulmonary congestion (on PE or CXR)
● Frank congestive heart failure
● Syncope
● Signs of shock
An important component in the management of a patient with any
tachycardia is to determine _____
whether a pulse is present or not.
If not, we move to cardiac arrest protocol
After determining whether a patient with a tachyarrhythmia has a pulse, we then need to determine ____
whether the patient is stable or unstable
ABCD approach to perform an initial assessment of bradycardia/tachycardia
○ Airway
○ Breathing
○ Circulation
Differential
Signs/symptoms that would signal an unstable tachycardia
○ Hypotension
○ Acutely altered mental status
○ Signs of shock
○ Ischemic chest discomfort
○ Acute heart failure
Synchronized Cardioversion
a form of shock therapy (like defibrillation)
where the delivery of a low-level energy dose is administered at the peak of the QRS complex (avoiding the T wave, or repolarization).
Unstable patients with tachycardia require ____
immediate cardioversion
Even if delivered as a synchronized shock, there is still a very small risk of
triggering VF; if this occurs, _____
immediately Defibrillate.
Synchronized shocks are recommended for patients with:
○ Unstable SVT
○ Unstable Atrial Fibrillation
○ Unstable Atrial Flutter
○ Unstable regular monomorphic VT
If the patient has regular narrow-complex SVT or a monomorphic wide-complex tachycardia and is NOT hypotensive, you may administer
______
adenosine while preparing for synchronized cardioversion.
If there is no response to the first shock for synchronized cardioversion, you can _____
Increase the dose in a
stepwise fashion and try again.
Treatment of stable narrow-complex tachycardias involves
○ Vagal Maneuvers (valsalva and/or carotid massage)
○ Adenosine
Cardioversion is contraindicated with a _____
sinus rhythm
Treating sinus tachycardia involves
Identifying and correcting the underlying problem causing the tachycardia (such as fever, anemia, hypovolemia, etc.)
The first-line treatment for stable narrow-complex tachycardia is generally
_____
attempting vagal maneuvers
○ These terminate supraventricular tachycardias about 25% of the time
Valsalva Maneuver
○ The idea is that increasing the intrathoracic pressure triggers changes in
the preload and afterload that result in initial tachycardia, followed by
increase in cardiac output, then an increased vagal response
Carotid Massage-
○ Massaging over the carotid bifurcation can also simulate a sudden
increase in cardiac output and BP, triggering increased vagal tone.
How to perform the carotid massage maneuver:
■ Auscultate for carotid bruits with the bell. If bruits are present, abort!
■ With the Pt lying flat, extend the neck and rotate the head slightly away from you.
■ Palpate the carotid artery at the angle of the jaw and apply gentle pressure for
10-15 seconds, right over carotid bifurcation.
■ Never compress both carotid arteries simultaneously.
■ Try the right carotid first (better success rate), but try left if right fails.
■ Have a rhythm strip running during the entire procedure so you can see what is
happening.
Adenosine indications
● If the narrow-complex tachycardia does not respond to vagal maneuvers, IV
administration of Adenosine is indicated
Adenosine is contraindicated in
2nd or 3rd degree AV block,
sinus node dysfunction, and signs/symptoms of acute myocardial ischemia.
Potential adverse effects of Adenosine include _____
cardiac arrest and myocardial infarction
After vagal maneuvers and adenosine, provide the patient with ______
Beta-Blocker or Calcium Channel Blocker can help to slow the rate and stabilize the ventricular conduction.
If the tachycardic patient was deemed as
Stable, assess ____
the width of the QRS
The common forms of stable, wide-complex tachycardias include:
○ Monomorphic VT
○ Polymorphic VT
○ SVT with Aberrancy
SVT with Aberrancy
○ Sometimes supraventricular beats can produce wide QRS complexes,
making it difficult to decide if it’s VT or SVT.
○ This occurs when a supraventricular beat is conducted “aberrantly”
through the ventricles (essentially abnormal purkinje conduction).
■ Produces wide, bizarre-looking QRS complexes
A few Clinical Clues for SVT with Aberrancy:
■ VT is more commonly seen in diseased hearts, while PSVT is more
commonly a concern in otherwise normal hearts.
■ Carotid massage has no effect on VT, but can terminate PSVT.
■ Cannon A Waves are sometimes seen with VT, but not PSVT.
● Visualization of forceful pulses in the neck (see next slide)
Cannon A Waves in VT
Produced when there is a sudden back-flooding of blood out of the heart,
into the jugular veins.
● Can occur sometimes in VT; does not occur in supraventricular tachycardia.
Some EKG Clues for SVT with Aberrancy:
■ If P waves are seen in PSVT, they march along with the QRS,
although they are usually inverted. Uncommonly, P waves are seen
with VT, and if so, they are completely dissociated
IV antiarrhythmic medications for Stable wide-complex tachy
Procainamide, Amiodarone, and Sotalol
Treatment of these stable, wide-complex tachycardias is centered on a few
different medication options and expert consultation, what are some of the options?
● IV Adenosine can be attempted for both treatment and diagnosis of regular, wide-complex monomorphic tachycardias.
● IV antiarrhythmic medications can be tried as well.
● Otherwise, in stable wide tachycardias, you have time to monitor the Pt and wait for expert consultation
