Electrical Therapy Principles Flashcards

Which waveform type is used by most modern defibrillators and requires less energy than older monophasic devices?

Answer: Biphasic waveform

Biphasic waveforms deliver current in two directions and are more effective at lower energy levels than monophasic waveforms.

When performing transcutaneous pacing, the rate for a symptomatic bradycardia patient is typically set to:

Answer: 60-80 bpm

Transcutaneous pacing for symptomatic bradycardia is typically initiated at 60-80 bpm to restore adequate perfusion.

A patient in ventricular fibrillation receives a shock but immediately returns to VF. What is the recommended next step?

Answer: Resume CPR for 2 minutes then reassess rhythm

After a failed shock, 2 minutes of high-quality CPR should resume to re-perfuse the myocardium before the next rhythm check.

What term describes the minimum current needed to reliably capture the myocardium during transcutaneous pacing?

Answer: Capture threshold

Capture threshold is the minimum milliamp output needed to consistently depolarize the myocardium and produce a mechanical response.

In synchronized cardioversion, the shock is timed to which part of the cardiac cycle?

Answer: QRS complex

Synchronized cardioversion delivers energy with the QRS complex to avoid the vulnerable T-wave period and prevent VF induction.

A patient with stable supraventricular tachycardia at 180 bpm does not respond to vagal maneuvers or adenosine. What electrical therapy is appropriate?

Answer: Synchronized cardioversion at 50-100J

Stable SVT refractory to medications is treated with synchronized cardioversion starting at 50-100J.

What is the PRIMARY danger of delivering a defibrillation shock in asynchronized mode to a patient in atrial flutter?

Answer: Inducing ventricular fibrillation by shocking on the T wave

Unsynchronized shocks during atrial flutter can coincide with the T wave's vulnerable period, triggering ventricular fibrillation.