Final answer:
The correct action for a patient who becomes unresponsive with polymorphic ventricular tachycardia post-ROSC is to administer an unsynchronized high-energy shock immediately.
Step-by-step explanation:
If a patient becomes unresponsive with polymorphic ventricular tachycardia after return of spontaneous circulation (ROSC), the indicated action is to administer an immediate unsynchronized high-energy shock. Synchronized cardioversion is not appropriate in this scenario as the irregular rhythm of polymorphic ventricular tachycardia does not allow for proper synchronization. Medication like lidocaine or amiodarone would typically follow defibrillation if the arrhythmia persists. Remember, the key in treating ventricular tachycardia (especially if the patient is pulseless) is rapid defibrillation.
Concerning internal calculations during procedures like open-heart surgery where a defibrillator might be used, knowing the required voltage for defibrillation can be calculated using Ohm's Law. Given that the resistance is 500 ohms and a 10.0-mA current is needed, the voltage equals the current multiplied by resistance, which would be 5 volts (V = IR).
Automated external defibrillators (AEDs) are now commonly found in public places and are designed to be used by laypersons. They diagnose the heart condition automatically and apply a shock with appropriate energy. This portable device can be critical in saving lives in cases of cardiac arrest due to ventricular fibrillation.
the corrct answer is C. Give lidocaine 1 to 1.5 mg/kg IV