What is the primary purpose of using an AED?

The primary purpose of using an AED, or Automated External Defibrillator, is to reset the heart rhythm during a cardiac arrest. In situations where a person experiences sudden cardiac arrest, their heart may be in a chaotic rhythm, such as ventricular fibrillation or pulseless ventricular tachycardia. An AED analyzes the heart's rhythm and, if necessary, delivers an electric shock to attempt to restore a normal rhythm. This shock can help revive the heart's natural pacing and increase the chances of survival if administered promptly.

The other options do not accurately represent the primary function of an AED. While providing oxygen is crucial in many medical emergencies, it is not a function of an AED; this is typically handled through ventilations in CPR. Monitoring vital signs is important in patient assessment but is not the role of the AED; it focuses solely on correcting dangerous heart rhythms. Lastly, while an AED is a vital tool in cardiac emergencies, it does not replace the need for CPR; rather, CPR and AED use should be performed in conjunction to maximize the chances of survival until advanced medical help arrives.