Final answer:
Controlled electrical shocks, delivered by a defibrillator, are used to treat ventricular fibrillation, with the number of shocks varying based on patient response and guidelines. Care is taken to avoid excessive currents that could cause cardiac damage or burns.
Step-by-step explanation:
When dealing with a medical condition like ventricular fibrillation (VF), it is crucial to apply electrical shocks to the heart in a controlled manner using a defibrillator. These shocks are given to restore normal heart rhythm. Defibrillation procedures often involve one initial shock followed by additional shocks if the first is not successful, and the number of shocks can vary depending on the patient's response and clinical guidelines. Importantly, the delivered current should not exceed thresholds that could induce further cardiac damage or burns. Typically, during open-heart surgery, the resistance of the heart path might be around 500 ohms, and a 10.0-mA current is required for defibrillation. For a resistance of 300 ohms, a 20.0 μA current may cause VF, so the voltage must be carefully calculated to avoid reaching the threshold for ventricular fibrillation which is between 100 and 300 mA.