ACLS ACLS Cardiac Rhythms & ECG Interpretation 2

Question 1

On a monitor strip, you see regular, wide QRS complexes at 180 bpm with no discernible P waves and the patient has a pulse. What is the most likely rhythm?

Accepted Answer

Ventricular tachycardia (VT) with pulse

Answer

Regular wide-complex tachycardia at 180 bpm with a pulse is treated as ventricular tachycardia until proven otherwise.

Question 2

Which ECG feature best differentiates a junctional rhythm from a sinus rhythm?

Accepted Answer

Absent, inverted, or retrograde P waves

Answer

Junctional rhythms originate in the AV node and produce absent, inverted, or retrograde P waves because atrial activation is not antegrade.

Question 3

A patient in cardiac arrest has no rhythm visible on the monitor (flat line). After confirming lead connections and gain, what is the appropriate ACLS action?

Accepted Answer

Continue high-quality CPR and administer epinephrine

Answer

Asystole is a non-shockable rhythm; management is high-quality CPR, epinephrine every 3–5 minutes, and investigation of reversible causes.

Question 4

Which ECG pattern is associated with hyperkalemia and should prompt immediate intervention?

Accepted Answer

Peaked (tall, narrow) T waves, widened QRS, flattened P waves

Answer

Hyperkalemia produces peaked T waves early, then PR prolongation, P wave flattening, wide QRS, and ultimately a sine-wave pattern that can degenerate into VF.

Question 5

A narrow-complex tachycardia at 160 bpm begins and terminates abruptly. Which rhythm does this pattern best describe?

Accepted Answer

Paroxysmal supraventricular tachycardia (PSVT)

Answer

PSVT (most commonly AVNRT) characteristically starts and stops abruptly, producing a regular narrow-complex tachycardia.

ACLS Practice Test

ACLS Practice Test

ACLS ACLS Cardiac Rhythms & ECG Interpretation 2