What is the indication for using a defibrillator?

A defibrillator is primarily indicated for the restoration of normal heart rhythm during life-threatening arrhythmias, specifically conditions such as ventricular fibrillation and pulseless ventricular tachycardia. When the heart's electrical activity becomes chaotic or stops altogether, defibrillation is a critical intervention that delivers an electrical shock to the heart. This shock helps to reset the heart's electrical system, allowing the heart to resume a normal rhythm and restore effective pumping.

In contrast, preventing bradycardia in stable patients does not require defibrillation, as bradycardia is a slow heart rate that may not pose an immediate life threat. Additionally, treating hypertension involves managing blood pressure through medications or lifestyle changes rather than electrical interventions. Lastly, enhancing cardiac output in heart failure typically focuses on pharmacologic treatments and optimizing heart function rather than using a defibrillator, which is specific to acute arrhythmias. Thus, the role of a defibrillator is crucially linked to the urgent need to address life-threatening arrhythmias.