Final answer:
An automated external defibrillator (AED) delivers a controlled electrical charge to correct an abnormal heart rhythm during a cardiac emergency, significantly more effective than a precordial thump. AEDs have become essential tools in ambulances and public places, designed for use by both medical personnel and the lay public following medical guidelines.
Step-by-step explanation:
Understanding Defibrillation and Cardiac Arrhythmias
During a cardiac emergency, the use of an automated external defibrillator (AED) can be critical in saving a patient´s life. A defibrillator works by delivering a controlled electrical charge to the heart to correct an arrhythmia, such as ventricular fibrillation, where the heart beats rapidly and irregularly. By providing a significant electrical shock, usually in the range of hundreds of joules, the defibrillator helps to stop the arrhythmia, allowing the heart's natural pacemaker to restore a normal rhythm.
In contrast, a precordial thump, a manual technique designed to interrupt a cardiac arrest, typically delivers a much lower energy level — 5-10 joules — which is generally insufficient to revert serious arrhythmias and therefore is not the preferred intervention if a defibrillator is readily available. Modern defibrillators are equipped with electrocardiograms (ECG) to analyze the patient's heart rhythm, ensuring the shock is delivered with the correct energy and waveform. CPR (cardiopulmonary resuscitation) is often recommended to support the patient until an AED becomes available or is used.
Most ambulances and many public places are equipped with AEDs, ensuring prompt emergency care for cardiac arrest victims. Defibrillators are life-saving tools that require careful handling, and while designed for use by the lay public in the case of AEDs, they should be used in accordance with established medical guidelines.