Final answer:
Epinephrine is the drug used to counteract shock refractory VF or pulseless tachycardia.
Step-by-step explanation:
In the case of shock refractory ventricular fibrillation (VF) or pulseless tachycardia, the drug that is commonly used is epinephrine. Epinephrine is a medication that stimulates the heart, constricts blood vessels, and can help restore normal heart rhythms. It is administered through intravenous (IV) or intraosseous (IO) routes. The student is asking which medication is used for shock refractory ventricular fibrillation (VF) or pulseless ventricular tachycardia. In such a scenario, where a patient is not responding to initial defibrillation, guideline-recommended medications include both epinephrine and amiodarone. Epinephrine is administered to increase coronary and cerebral blood flow during CPR and is provided every 3-5 minutes during cardiac arrest. Amiodarone can be given for VF or pulseless ventricular tachycardia that is unresponsive to CPR, defibrillation, and vasopressor therapy. Lidocaine is an alternative to amiodarone but has a lower priority, and dopamine is generally not indicated for this specific scenario.