Also known as Automated External Defibrillator (AED), Implantable Cardioverter Defibrillator (ICD), Wearable Cardioverter Defibrillator (WCD).

Defibrillators are devices that restore a normal heartbeat by sending an electric pulse or shock to the heart. They are used to prevent or correct an arrhythmia, a heartbeat that is uneven or that is too slow or too fast. Defibrillators can also restore the heart’s beating if the heart suddenly stops.

Have you ever wondered what they’re doing in the movies when the doctor yells ‘clear!’ and delivers an electrical shock to a patient? Explore this Health Topic to learn more about it & defibrillators.

Types of defibrillators

  • Manual external defibrillator
  • Automated external defibrillator (AED)
  • Advanced Life Support Units
  • Wearable Cardioverter Defibrillators

Automated external defibrillator (AED)

What Is an Automated external defibrillator (AED)?

An automated external defibrillator (AED) is a lightweight, portable device that delivers an
electric shock through the chest to the heart. The shock can potentially stop an irregular heart
beat (arrhythmia) and allow a normal rhythm to resume following sudden cardiac arrest (SCA).
SCA occurs when the heart malfunctions and stops beating unexpectedly. If not treated within minutes, it quickly leads to death.
Most SCAs result from ventricular fibrillation (VF). VF is a rapid and unsynchronized heart rhythm that originates in the heart’s lower chambers (the ventricles). The heart must be “defibrillated” quickly, because a victim’s chance of surviving drops by seven to 10 percent for every minute a normal heartbeat isn’t restored.

Why are AEDs important?

AEDs make it possible for more people to respond to a medical emergency where defibrillation is required. Because AEDs are portable, they can be used by nonmedical people (lay-rescuers). They can be made part of emergency response programs that also include rapid use of 9-1-1 and prompt delivery of cardio pulmonary resuscitation (CPR). All three of these activities are vital to improving survival from SCA.

How does an AED work?

A built-in computer checks a victim’s heart rhythm through adhesive electrodes. The computer calculates whether defibrillation is needed. If it is, a recorded voice prompts the rescuer to press the shock button on the AED. This shock momentarily stuns the heart and stops all activity. It gives the heart the chance to resume beating effectively. Audible prompts guide the user through the process. AEDs advise a shock only for ventricular fibrillation or another life-threatening condition called pulseless ventricular tachycardia.

Who can use an AED?

Non-medical personnel such as police, fire service personnel, flight attendants, security guards and other lay rescuers who have been trained in CPR can use AEDs. Although formal training in the use of an AED is not required, it is recommended to help the rescuer increase their comfort and level of confidence. However, AED sare intended for use by the general public. Most AEDs use audible voice prompts to guide the user through the process.

Are AEDs safe to use?

AEDs are safe to use by anyone. Some studies have shown that 90 percent of the time AEDs are able to detect a rhythm that should be defibrillated. This data suggests that AEDs are highly effective in detecting
when (or when not) to deliver a shock.

Who needs defibrillators?

  • AEDs. AEDs save the life of someone in cardiac arrest and you can use them for children and adults alike, though you will have to use special pads for children. During cardiopulmonary resuscitation or CPR, AEDs can improve their chances of survival.
  • WCDs. WCDs protect against cardiac arrest in certain circumstances. If you are at risk of arrhythmias for a shorter period, such as recovering from a heart attack, awaiting a heart transplant, or fighting an infection, WCDs are ideal.
  • ICDs. ICDs correct more severe cases of arrhythmias. These types of arrhythmias can be fatal and can develop at any age, from newborns to adults. ICDs are used for anyone with an arrhythmia that causes your heart ventricles to quiver or spasm.

Cases that call for ICDs

  • You survived cardiac arrest.
  • You developed an arrhythmia during or after treatment for a heart attack.
  • You have genetic conditions.
  • You have a neuromuscular disorder.
  • You have an abnormally slow heart rate.
  • You have cardiac sarcoidosis.
  • You have poor heart functioning.
  • Your doctor detected an arrhythmia via an EKG scan.

Pros And Cons of Defibrillators


  • Are easy Accessable
  • Are very effective


  • Are expensive machines
  •  Require training to use properly

Best Automated External Defibrillator To Buy:

Philips AED HeartStart HS1/ Onsite Automatic External Defibrillator


Philips AED Heartstart HS1/Onsite Specification :-

  1. Kit Contents  : Defibrillator, battery (one, pre-installed), SMART Pads (one set, pre-installed), set-up/maintenance guide with expiration date tags, owner’s manual, quick reference guide.
  2. Waveform : SMART Truncated exponential biphasic. Waveform parameters adjusted as a function of patient impedance
  3. Defibrillation peak current – Adult : 32 A (150 J nominal) into a 50 ohm load
  4. Defibrillation peak current – Pediatric : 19 A (50 J nominal) into a 50 ohm load (using optional infant/child SMART Pads Cartridge)
  5. Shock-to-Shock Cycle Time : Typically less than 20 seconds between shocks in a series
  6. Quick Shock : Able to deliver a shock after the end of a CPR interval, typically in eight seconds

Philips Heartstart FRx AED ( Automatic External Defibrillator)


Brand : PhilipsModel : Heartstart FRx 

Philips Heartstart FRx AED Specification :

The HeartStart FRx defibrillator provides real-time guidance through simple, step-by-step voice commands, an audible metronome and CPR coaching to help guide the treatment of a suspected sudden cardiac arrest. With easy set-up, clear voice prompts, and rugged design, HeartStart FRx is designed for users trained in Basic Life Support (BLS).

  • Adult defibrillation peak current : 32A (150J nominal) into a 50 ohm load.
  • Pediatric defibrillation (with optional Infant/Child Key installed) : 19A (50J nominal) into a 50 ohm load 
  • Temperature : Operating/Standby:32° – 122° F (0° – 50° C)

Mediana Semi Automatic Defibrillator, HeartOn AED A15


Brand : MedianaModel : Hearton AED A15

Mediana Semi Automatic Defibrillator, HeartOn AED A15  Features:-

  • COVER Icon sheet protection, shock button, adult / pediatric switch
  • CONNECTING SOCKET Connector socket for defibrillator pads. Always prepared to use the pads
  • VISUAL ICONS LED With the respective voice prompts, indicator lights flash. Visual icons explain the activities needed.
  • SPEAKER Acoustic indicator for real-time guidance.
  • ADULT/PAEDIATRIC MODE SWITCH Without altering the pads, easily switch from adult to pediatric mode.
  • STATUS INDICATOR Status of unit, status of battery level and status of temperature range.
  • SD CARD INSERT Review stored data and upgrade software.

Niscomed Automated External Defibrillator AED-7000


Brand : NISCOMEDModel : AED 7000

Three-step defibrillation process : 

  • Two-button operation
  • Extensive voice and visual prompts for the operator
  • Biphasic energy output
  • Lock-out protection to prevent inadvertent defibrillation
  • PC-based event review (Optional)
  • Multillingual Selections are available (Optional)
  • The Niscomed Automated External Defibrillator is a defibrillation device, which is safe, portable and easy to use
  • The device can be used in family or in public place to provide first aid for the sudden death symptom
  • Combined with advanced ECG analytical technique, the defibrillator can analyze the patients ECG and make a judgement for the patients cardiac condition and indicate whether the defibrillation is needed
  • The machine not only enhances the success rate of defibrillation, but also reduce the injury of defibrillation to heart to the utmost extent
  • There is low requirement for the operator to use the device. The defibrillator will guide the operator to carry out defibrillation treatment via voice prompt. The machine provides step by step safety alert if the occasion arises.

Philips HeartStart FR3 AED , Automatic External Defibrillator


Brand : PhilipsModel : Heartstart FR3

Philips HeartStart FR3 AED SPECIFICATION :-

  • Screen – LCD color display, 320 x 240 pixels.(7.2 cm x 5.4 cm)
  • Dimensions (H x W x D) – (6.9 cm x 13.5 cm x 22.1 cm)
  • Weight –1.6 kg with FR3 primary battery installed
  • Monitored lead – Lead II using anterior-anterior adult pads placement
  • Shock/drop – Abuse tolerance Meets MIL-STD-810F 516.5, Procedure IV
  • Function – Stores a minimum of 8 hours of ECG, event, and, if configured, voice recording. Can also be used for configuring FR3


Defibrillation is a life-saving treatment for cardiac dysrhythmias such as ventricular fibrillation (VF) and non-perfusing ventricular tachycardia (NPVT) (VT). A defibrillator shocks the heart with an electric current (known as a counter-shock). Although the exact mechanism is unknown, this process depolarizes a huge portion of the heart muscle, putting an end to the dysrhythmia. The body’s natural pacemaker, located in the sinoatrial node of the heart, is then able to restore normal sinus rhythm. A defibrillator cannot restart a heart that is in asystole (flatline), but it can be treated with cardiopulmonary resuscitation (CPR). Synchronized electrical cardioversion, in contrast to defibrillation, is an electrical shock administered in time with the heart cycle. Cardioversion is used to treat poorly perfusing cardiac dysrhythmias such as supraventricular tachycardia, even if the patient is still severely unwell. Depending on the type of device used or required, defibrillators can be external, transvenous, or implanted (implantable cardioverter-defibrillator). Automated external defibrillators (AEDs) are external machines that automate the detection of treatable arrhythmias, allowing lay responders or bystanders to use them successfully with little or no training.