What type of electrical current is used in defibrillators?

• A. Alternating Current (AC)
• B. Direct Current (DC)
• C. Pulsed Current
• D. Low Voltage Current

Answer: (B)

Defibrillators use direct current (DC) to deliver a therapeutic shock to the heart in cases of certain types of cardiac arrhythmias, such as ventricular fibrillation or pulseless ventricular tachycardia. The use of direct current is critical because it results in a single, high-energy shock that depolarizes the heart muscle simultaneously, allowing normal electrical conduction to resume.

While alternating current (AC) is more commonly used in other electrical applications, it is not suitable for defibrillation due to its oscillating nature, which can disrupt the heart's rhythm rather than restore it. Pulsed current may be used in other therapeutic applications but does not achieve the desired outcome in the critical moment of defibrillation. Low voltage current does not provide the necessary energy levels required for effective defibrillation, making direct current the optimal choice for this urgent medical procedure.