What is the defibrillation energy setting for biphasic waves?

The correct energy setting for biphasic defibrillation is typically in the range of 120 to 200 joules. This setting is derived from numerous studies and clinical guidelines that indicate biphasic waveforms are more effective and require lower energy levels compared to traditional monophasic defibrillation. Biphasic defibrillators deliver electrical pulses that flow in two different directions, which not only increases the likelihood of successful cardioversion or defibrillation but also reduces the energy required to achieve that success.

Using the 120-200 joule setting helps to minimize the risk of damage to the myocardium while providing effective defibrillation, thereby improving outcomes in patients experiencing life-threatening arrhythmias such as ventricular fibrillation or pulseless ventricular tachycardia.

Choosing a setting significantly below or above this range—like the lower or higher end in the other options—may lead to inadequate electrical dose delivery or increased risk of tissue damage, which is why the recommended range is emphasized in clinical practice.