Cardiac arrest VF/VT vs Cardiac arrest PEA/asystole
How to tell Cardiac arrest VF/VT and Cardiac arrest PEA/asystole apart when a board question makes them look alike.
Step 2 CK pairs are in open beta while clinical review finishes. Spot an issue? Tell us.
Shockable monitor rhythm defines VF or pulseless VT, while PEA or asystole are nonshockable.
Side by side
Pulseless ventricular fibrillation or pulseless ventricular tachycardia is a shockable arrest rhythm.
Pulseless electrical activity or asystole is a nonshockable arrest rhythm requiring CPR and epinephrine with reversible-cause search.
Chaotic or rapid ventricular electrical activity prevents effective cardiac output but can be terminated by defibrillation.
Electrical or near-electrical silence without effective mechanical contraction reflects severe underlying reversible insult.
VF or pulseless VT on monitor requires immediate unsynchronized shock, then high-quality CPR, epinephrine 1 mg IV every 3 to 5 minutes, and amiodarone 300 mg IV bolus after refractory shocks.
PEA or asystole has organized activity without pulse or flatline pattern, managed with CPR and epinephrine every 3 to 5 minutes plus rapid Hs and Ts correction; defibrillation is not indicated.
The trap
Epinephrine is given first in VF and defibrillation is delayed, or shocks are inappropriately delivered to asystole. Rhythm-directed branching in the first seconds determines survival.
The repair move
Next best step: for VF or pulseless VT, defibrillate immediately at biphasic 200 J, resume CPR for 2 minutes, give epinephrine 1 mg IV every 3 to 5 minutes, and give amiodarone 300 mg IV for refractory shockable rhythm. For PEA or asystole, do high-quality CPR plus epinephrine and aggressively treat reversible causes without defibrillation.
Try a free question
CoreA pulseless patient is found in ventricular fibrillation on monitor during ACLS. What is the next best step in management?
Show answer and explanation
Answer: A. Immediate unsynchronized defibrillation. VF is a shockable arrest rhythm and requires immediate defibrillation.
Why the other choices are tempting
- B. Wrong. Lab testing should not delay life-saving defibrillation.
- C. Wrong. Atropine is not first-line for VF arrest.
- D. Wrong. Procedural delays reduce survival in shockable arrest.
- E. Wrong. Synchronized mode is not used in pulseless VF.
Flashcards
Tap a card to flip it.
Which arrest rhythms are immediately shockable?
Ventricular fibrillation and pulseless ventricular tachycardia.
What medication timing is standard during ongoing ACLS cycles?
Epinephrine 1 mg IV every 3 to 5 minutes.
Quick answers
What is the fastest way to tell Cardiac arrest VF/VT from Cardiac arrest PEA/asystole?
Shockable monitor rhythm defines VF or pulseless VT, while PEA or asystole are nonshockable.
What is the key clue for Cardiac arrest VF/VT?
Pulseless ventricular fibrillation or pulseless ventricular tachycardia is a shockable arrest rhythm.
What is the key clue for Cardiac arrest PEA/asystole?
Pulseless electrical activity or asystole is a nonshockable arrest rhythm requiring CPR and epinephrine with reversible-cause search.
What is the common trap with Cardiac arrest VF/VT vs Cardiac arrest PEA/asystole?
Epinephrine is given first in VF and defibrillation is delayed, or shocks are inappropriately delivered to asystole. Rhythm-directed branching in the first seconds determines survival.