MS3 Cardiac (2) 10Q

The nurse is preparing a client for synchronized cardioversion. Which cardiac rhythm would require this treatment?

• Ventricular fibrillation

• Atrial fibrillation with rapid ventricular response

• Asystole

• Pulseless ventricular tachycardia

Answer explanation

Rationale:
Synchronized cardioversion is used for unstable tachydysrhythmias with a pulse, such as atrial fibrillation with rapid ventricular response (means the rate is too fast, over 100 beats/minute). The shock is synchronized with the R wave to prevent the induction of lethal dysrhythmias. Ventricular fibrillation and pulseless ventricular tachycardia require immediate defibrillation, whereas asystole is treated with CPR and pharmacologic interventions rather than electrical therapy.

A client develops pulseless ventricular tachycardia. CPR is started and the crash (code) cart has been brought to the client’s bedside. Which intervention is most appropriate?

• Perform synchronized cardioversion

• Initiate immediate defibrillation

• Administer atropine

• Place the client in a Trendelenburg position

Answer explanation

Rationale:
Pulseless ventricular tachycardia is treated with immediate defibrillation as part of ACLS guidelines. Defibrillation is also known as an unsynchronized shock, or sometimes just a "shock". Without a pulse, cardioversion is ineffective since it requires synchronization with the R wave, which is not identifiable. Atropine is used for bradycardia, and Trendelenburg positioning does not address the immediate life-threatening dysrhythmia. There was not an option for CPR, if there was, that would have been the answer. Remember when we have a lethal dysrhythmia, the only treatment that will usually work is an electrical shock (to shock back into a SR)

The nurse is preparing to deliver a defibrillation shock to a client in ventricular fibrillation. Which actions must be followed?

• Ensure everyone is clear of the client before delivering the shock

• Continue chest compressions while the shock is delivered

• Place pads firmly on the client’s chest according to manufacturer guidelines

• Verify the defibrillator is in synchronized mode

• Ensure defibrillation is performed immediately without delay

Answer explanation

Rationale:
During defibrillation, ensuring that no one is touching the client before delivering the shock is crucial for safety. Pad placement should be correct for optimal energy transfer. Defibrillation must be performed immediately when indicated. Chest compressions should be paused during shock delivery. "Synchronized" mode is not used in defibrillation; it is needed only for cardioversion. Remember, when we "SYNCHRONIZE" the electrical stimulation, we want the shock to hit during "R" wave, not the "T" wave, because the ventricles are "resting" or "repolarizing" before their next contraction.

The nurse is caring for a client with ventricular tachycardia who is alert and has a pulse. Which interventions are appropriate for the nurse to take?

• Prepare for synchronized cardioversion if the client is unstable

• Administer antiarrhythmic medications as prescribed

• Initiate immediate defibrillation

• Continue monitoring if the client remains asymptomatic

• Perform chest compressions immediately

Answer explanation

Rationale:
For a client with ventricular tachycardia and a pulse, synchronized cardioversion is indicated if instability develops. Antiarrhythmic medications may be used for rhythm control. If the client is asymptomatic and hemodynamically stable, ongoing monitoring is appropriate. Immediate defibrillation and chest compressions are reserved for pulseless ventricular tachycardia.

The nurse is caring for a client with newly diagnosed atrial fibrillation. Which actions should be included in the plan of care that are are directly related to the dysrhythmia?

• Administer anticoagulants as prescribed

• Instruct the client to avoid foods high in vitamin K

• Encourage the client to perform deep breathing exercises

• Prepare the client for emergency defibrillation

• Monitor for signs of embolic complications

Answer explanation

Rationale:
Anticoagulation is a cornerstone of atrial fibrillation management to reduce the risk of embolic events such as stroke. Avoiding foods high in vitamin K is necessary if the client is receiving warfarin. Monitoring for embolic complications is essential due to increased clot formation risk. While rate control may be necessary, deep breathing exercises alone are unlikely to significantly impact atrial fibrillation. Emergency defibrillation is reserved for unstable ventricular dysrhythmias, not atrial fibrillation

Which cardiac rhythm is most commonly treated with unsynchronized defibrillation?

• Sinus bradycardia

• Ventricular fibrillation

• Atrial flutter

• First-degree heart block

Answer explanation

Unsynchronized defibrillation is most commonly indicated for ventricular fibrillation because this rhythm involves chaotic, disorganized electrical activity with no effective cardiac output, making it immediately life-threatening. Defibrillation delivers a high-energy shock without timing it to the cardiac cycle, which is necessary because there is no identifiable R wave to synchronize with in ventricular fibrillation. The goal is to depolarize the myocardium simultaneously so that normal pacemaker activity can resume. Sinus bradycardia is usually treated with atropine or pacing, atrial flutter is typically managed with synchronized cardioversion or pharmacologic therapy if unstable, and first-degree heart block generally requires no emergent electrical intervention.

During a cardiac arrest, which medication is most appropriate to administer for ventricular fibrillation after defibrillation?

• Adenosine

• Digoxin

• Atropine

• Amiodarone

Answer explanation

During a cardiac arrest with ventricular fibrillation that persists after defibrillation, amiodarone is the most appropriate medication to administer. Amiodarone is an antiarrhythmic that works by prolonging the action potential and refractory period, helping to stabilize the myocardium and improve the likelihood of achieving a return of spontaneous circulation (ROSC) when used in conjunction with high-quality CPR and defibrillation. Adenosine is used for stable supraventricular tachycardias, digoxin is indicated for rate control in atrial fibrillation and heart failure but is not used in cardiac arrest, and atropine is used to treat symptomatic bradycardia, not ventricular fibrillation.

What is the first action a nurse should take when a patient is found unresponsive with no pulse and ventricular fibrillation on the monitor?

• Administer epinephrine

• Apply oxygen via mask

• Begin chest compressions

• Perform synchronized cardioversion

Answer explanation

When a patient is unresponsive, pulseless, and in ventricular fibrillation, the priority action is to initiate high-quality chest compressions immediately. Early CPR maintains minimal cerebral and coronary perfusion and improves the effectiveness of subsequent defibrillation. While defibrillation is essential for ventricular fibrillation, CPR should begin right away while the defibrillator is being prepared. Epinephrine is administered later in the ACLS algorithm, oxygen via mask is not effective without circulation, and synchronized cardioversion is inappropriate for pulseless rhythms.

Which cardiac rhythm is an indication for immediate unsynchronized defibrillation?

• Supraventricular tachycardia

• Sinus tachycardia

• Ventricular fibrillation

• Second-degree heart block

Answer explanation

Ventricular fibrillation requires immediate unsynchronized defibrillation because it is a chaotic, disorganized rhythm that produces no cardiac output. Defibrillation delivers a high-energy shock without timing it to the cardiac cycle, which is necessary because there is no identifiable R wave. Supraventricular tachycardia and sinus tachycardia are typically treated with medications or synchronized cardioversion if unstable, and second-degree heart block is usually managed with pacing or pharmacologic support, not defibrillation.

Which of the following is the most appropriate initial intervention for a patient experiencing asystole?

• Apply synchronized cardioversion

• Perform unsynchronized defibrillation

• Begin chest compressions and administer epinephrine

• Administer adenosine

Answer explanation

Asystole is a non-shockable rhythm characterized by the absence of electrical activity. The most appropriate initial intervention is immediate high-quality CPR combined with epinephrine administration to support coronary and cerebral perfusion and stimulate cardiac activity. Defibrillation and synchronized cardioversion are ineffective in asystole due to the lack of electrical activity, and adenosine is used for supraventricular tachycardias, not cardiac arrest rhythms.