ACLS ProMed Practice Test

When amiodarone isn’t available, lidocaine can be used as the next best antiarrhythmic for refractory ventricular fibrillation or pulseless ventricular tachycardia. Lidocaine is a class IB sodium channel blocker that preferentially stabilizes ischemic ventricular tissue, decreases automaticity, and dampens ventricular ectopy. This helps to terminate or suppress ongoing chaotic ventricular activity and supports the overall resuscitation effort. In practice, give a bolus of 1–1.5 mg/kg IV, and if needed, another 0.5–0.75 mg/kg every 5–10 minutes, up to about 3 mg/kg total; an infusion (1–4 mg/min) can be continued if ongoing therapy is required.

Adenosine isn’t effective for VF/pVT, as its role is mainly in certain supraventricular rhythms. Magnesium sulfate is reserved for torsades de pointes or magnesium deficiency, not generic refractory VF/pVT. Propranolol is a beta-blocker and isn’t used for acute resuscitation of VF/pVT due to its potential to worsen hemodynamics. Amiodarone remains the preferred agent when available, but lidocaine serves as an appropriate alternative in its absence.