Final answer:
Controlled electric shocks are used to interrupt shockable rhythms like ventricular fibrillation, allowing the heart to 'reboot' and restore a normal rhythm. Very large currents stop the heart temporarily but often restore normal function post-shock, erasing the abnormal electrical patterns. Large paddles spread the current to reduce burns, and LL lead monitors effectiveness during defibrillation.
Step-by-step explanation:
When dealing with shockable rhythms, such as ventricular fibrillation or pulseless ventricular tachycardia, the application of a controlled electric shock can be lifesaving. This intervention, known as defibrillation, utilizes currents to interrupt the erratic electrical activity of the heart. A very large current causes both the heart and the diaphragm to contract for the duration of the shock, resulting in a temporary cessation of the heartbeat and breathing. Interestingly, both often return to normal once the shock is over. Defibrillation effectively erases the abnormal electrical patterns on the heart, allowing it to restart with a normal rhythm, in contrast to smaller currents that can induce persistent ventricular fibrillation.
When using defibrillation, large paddles are often shown in media representations. These paddles distribute the electric current over a wider surface area to minimize burns. The electrodes placed on the patient during this procedure, such as the Left Branch (LL) lead in ECG readings, help monitor the heart's electrical activity and ensure the shock is delivered effectively.