What is the initial energy for synchronized cardioversion of an unstable tachyarrhythmia with wide QRS?

What is the initial energy for synchronized cardioversion of an unstable tachyarrhythmia with wide QRS?

• A. 50 J
• B. 200 J
• C. 360 J
• D. 100 J (device-dependent; follow manufacturer)

Answer: (D)

Energy selection for synchronized cardioversion depends on the defibrillator type, so you must follow the device manufacturer’s instructions. In unstable tachyarrhythmias with wide QRS, synchronized cardioversion is used to restore rhythm with the lowest effective energy while avoiding unnecessary myocardial injury. Modern biphasic devices usually start around 100 J, whereas older monophasic devices typically require about 200 J. Because the starting energy isn’t universal across machines, the best practice is to use the energy recommended by the device’s guidelines and escalate if needed. That’s why the most accurate answer is to follow the manufacturer, since the exact starting setting varies by equipment.

Energy selection for synchronized cardioversion depends on the defibrillator type, so you must follow the device manufacturer’s instructions. In unstable tachyarrhythmias with wide QRS, synchronized cardioversion is used to restore rhythm with the lowest effective energy while avoiding unnecessary myocardial injury. Modern biphasic devices usually start around 100 J, whereas older monophasic devices typically require about 200 J. Because the starting energy isn’t universal across machines, the best practice is to use the energy recommended by the device’s guidelines and escalate if needed. That’s why the most accurate answer is to follow the manufacturer, since the exact starting setting varies by equipment.