Which of the following is NOT a treatment for Paroxysmal Supraventricular Tachycardia (PSVT)?

Choice A rationale

Setting the defibrillator in asynchronous mode and charging to 300 joules is contraindicated for synchronized cardioversion. Asynchronous shocks deliver energy regardless of the cardiac cycle, potentially striking during the vulnerable repolarization phase (T wave) and precipitating ventricular fibrillation. Synchronized cardioversion requires synchronized discharge on the R wave, using typically 50–100 joules for atrial flutter, ensuring depolarization of abnormal reentrant circuits without inducing malignant arrhythmias.

Choice B rationale

Gradual voltage increase until beats are captured describes pacing, not cardioversion. Electrical pacing delivers low-energy impulses to stimulate myocardial depolarization, used for bradyarrhythmias rather than atrial flutter. Cardioversion requires a single synchronized shock to terminate reentrant tachyarrhythmias by depolarizing cardiac tissue simultaneously, interrupting the abnormal conduction loop. Incremental voltage adjustment would be ineffective and potentially arrhythmogenic in tachydysrhythmic conditions.

Choice C rationale

Sedation before synchronized cardioversion prevents pain and anxiety because the electrical shock, though brief, causes skeletal muscle contraction and discomfort. Short-acting benzodiazepines or propofol are commonly administered per protocol. Cardioversion is synchronized with the R wave to restore sinus rhythm safely. Pre-procedure sedation ensures patient comfort, minimizes sympathetic stimulation, and prevents recall of the event while maintaining airway reflexes and hemodynamic stability.

Choice D rationale

Intubation is not routinely required for synchronized cardioversion in stable patients. Airway stabilization is necessary only if respiratory compromise or deep sedation occurs. Cardioversion is typically performed under short procedural sedation using non-paralyzing agents. Routine intubation would unnecessarily increase procedural risk and delay rhythm restoration in hemodynamically stable patients with atrial flutter. Continuous monitoring ensures airway protection without mandatory endotracheal intervention.

Choice A rationale

Administering epinephrine is typically reserved for pulseless electrical activity (PEA) or asystole during cardiac arrest. It is not the initial, first action for a wide-complex tachycardia where the patient's stability is yet to be determined by a prompt clinical assessment, which guides further therapy.

Choice B rationale

The initial and most crucial action in any sudden rhythm change, especially a potentially life-threatening wide-complex tachycardia (e.g., Ventricular Tachycardia), is to quickly assess the patient's hemodynamic stability, primarily by checking their level of consciousness, pulse, and blood pressure. This assessment determines the subsequent treatment, such as immediate cardioversion/defibrillation if the patient is unstable or antiarrhythmics if stable.

Choice C rationale

While a 12-lead ECG is essential for definitive diagnosis of the rhythm, it is not the first action. The immediate priority is the patient's stability, and treatment, guided by the patient's status, should precede the time taken to obtain a comprehensive ECG tracing.

Choice D rationale

Immediate defibrillation is indicated only if the patient with wide-complex tachycardia is pulseless (Ventricular Fibrillation or pulseless Ventricular Tachycardia). The nurse must first assess the patient's hemodynamic status (e.g., level of consciousness, presence of a pulse) to determine the appropriate intervention before proceeding with defibrillation. —.