When assisting with defibrillating an adult client who has gone into ventricular fibrillation, what must the nurse do?

Choice A rationale:

Blocking impulse transmission to the AV node is not the primary function of an ICD. This is typically achieved through medications such as beta blockers or calcium channel blockers, or through a procedure called AV node ablation.

While ICDs can sometimes have a secondary effect of slowing AV node conduction, their primary purpose is to actively monitor heart rhythm and deliver electrical shocks when necessary to restore normal rhythm.

Choice B rationale:

Assuming the function of the SA node is not the primary function of an ICD. The SA node, located in the right atrium, is the natural pacemaker of the heart, responsible for initiating electrical impulses that trigger each heartbeat.

While ICDs can sometimes pace the heart if the SA node is not functioning properly, their primary purpose is to intervene when life-threatening arrhythmias occur, rather than to continuously regulate heart rate.

Choice C rationale:

Triggering electrical impulses to the heart is the core function of an ICD. It continuously monitors heart rhythm and can deliver electrical shocks to restore normal rhythm when it detects potentially dangerous arrhythmias, such as ventricular tachycardia or ventricular fibrillation.

These shocks are designed to interrupt chaotic electrical activity in the heart and allow the natural pacemaker to regain control, preventing cardiac arrest and sudden cardiac death.

Choice D rationale:

Increasing ventricular conduction is not the primary function of an ICD. In fact, in some cases, ICDs may actually slow down ventricular conduction to prevent certain types of arrhythmias.

Medications or procedures such as cardiac resynchronization therapy (CRT) are specifically designed to improve ventricular conduction in patients with heart failure.

Choice A rationale:

Incorrect. PVCs are not caused by a malfunctioning SA node. The SA node is responsible for initiating the normal heartbeat, while PVCs originate from the ventricles. The underlying cause of PVCs can vary, but it's not directly related to SA node dysfunction. Choice C rationale:

Incorrect. Ventricular tachycardia (VT) is a rapid heart rhythm originating from the ventricles, typically defined as three or more consecutive PVCs. Two PVCs in a row are usually classified as a couplet, not VT.

Choice D rationale:

Incorrect. While PVCs are often harmless, they can sometimes be associated with underlying heart disease or lead to complications, especially if they are frequent or occur in specific patterns. Therefore, careful assessment and potential treatment are necessary.

Choice B rationale:

Correct. Treatment for PVCs is generally only recommended if the patient experiences concerning symptoms or if the PVCs are associated with a risk of developing more serious arrhythmias. Additionally, the QRS complex on the EKG/ECG should be evaluated. A narrow QRS complex during PVCs typically suggests a less concerning origin within the ventricles, while a wide QRS complex may indicate a higher risk of complications.