Automated External Defibrillator: What is an AED Device?

2022-04-06

AED solution for station

Have you ever noticed in medical-related movies or TV shows that doctors use two external paddles placed on the patient's chest to deliver an electric shock to save the patient in many first aid scenes? The device that doctors use has a technical medical term called a manual external defibrillator (MED) and is designed for medical professionals. The defibrillator is primarily used to defibrillate a patient in sudden cardiac arrest (SCA) to restore a regular heart rhythm.


At the same time, there is also an automated external defibrillator (AED) designed for bystanders without a medical background to initiate a real-time response to an out-of-hospital SCA. It is a portable defibrillator that can be used at home and in many public places.


But do you really know what an AED is and how to use an AED? If not, the post will take you through the ultimate guide of AED equipment.

AED solution for station
AED wall-mounted solution

What is an AED Device?

AED is a portable device about the size of a woman's handbag that is usually placed in a special AED box and installed in public or private places through a wall-mounted solution. When someone suffers a sudden cardiac arrest, bystanders can quickly find these devices according to the obvious AED box for SCA rescue.


A complete AED kit includes a machine, a pair of AED replacement pads, and a disposable battery. When the AED device is activated, it can automatically analyze the patient's heart rhythm to determine if a shock is needed. If the shock conditions allow, the AED equipment delivers a shock through AED pads attached to the correct location on the patient's chest to restore normal heart rhythm.


Classification of AEDAutomated external defibrillators can be divided into fully automated external defibrillators and semi-automated external defibrillators, depending on whether the device delivers the shock automatically. Fully automatic AED only requires the responder to correctly apply the AED pads to the patient and leave the rest of the work to AED. Semi-automatic AED is fully automated except for the manual push of a button to deliver the shock when the machine is instructed.


Depending on the defibrillation technique, AED can be divided into biphasic defibrillators and monophasic defibrillators. Nowadays, leaders in AED industry, e.g, Mindray, are using biphasic waveform technology in their AED device to deliver the shock as it is considered to be more effective and less harmful to patients. 


When is AED Equipment Needed?

Automated external defibrillators are commonly used for cardiovascular conditions such as cardiac arrest when a malfunction in the heart's electrical system causes a fatal rapid heartbeat (ventricular tachycardia) or a rapid and irregular heartbeat (ventricular fibrillation). Cardiac arrest occurs without warning, and within the first few minutes, blood flow to the brain becomes less available and eventually causes the patient to lose consciousness and awareness, resulting in permanent damage to the brain and other organs. Unless emergency treatment is started immediately, death will follow.


Cardiopulmonary resuscitation (CPR) and defibrillation are the most effective solutions for saving a patient with SCA. CPR retains enough oxygen in the lungs and delivers it to the brain, and defibrillation restores a normal heart rhythm by administering an electric shock to the patient's chest.

portable-aed-equipment
Portable AED equipment

AED equipment is specifically designed for such emergency scenarios to address the regret that emergency medical services (EMS) cannot arrive at the scene within 3-5 minutes of the prime rescue time but allow bystanders to perform real and effective defibrillation to save a life.[1] Studies have shown that the survival rate of out-of-hospital SCAs increase 2.62 times through bystander use of an automated external defibrillator to save lives.[2]


How to use an AED?

AED manufacturers have designed the machine to be smart and convenient enough as much as possible for everyone to access. Nonetheless, it is necessary to understand how to use an AED so that you are able to carry out rescue smoothly in case of actual rescue. Please review the detailed steps for using an AED device.

  1. Check to see if the person is breathing and has a pulse. If you see someone collapse in a public place, first check if he or she is breathing and has a pulse. If fail to feel a pulse and the person is not breathing, immediately call 911 and ask other people to find an AED device. After that, lay the patient flat on his/her back and perform CPR. The steps for CPR were covered in our previous article: How to Perform CPR on an Athlete and Use a Durable AED? Click on the link to learn more. 
  2. Get access to AED. Find the AED near you and turn on the device, follow the guidance and provide rescue.
  3. Place the AED pads. Undress the patient and place the AED pads on the patient's chest according to the voice prompts. For an adult, place one AED pad on the upper right side of the chest and the other AED pad on the lower left side of the chest, a few inches below the left armpit.
  4. Analyzes the heart rate and deliver an electrical shock. When the electrode pads are sensed in place, the AED automatically measures the heart rhythm and determines if an electric shock is needed. If so, the machine tells to back off and deliver an AED shock (in the case of a semi-automatic AED, a shock button needs to be pressed).
  5. Perform CPR. After the AED shock delivery, you will be guided to perform repeated CPR on the patient until emergency responders take over.
how-to-use-an-aed
How to use an AED

AED Safety Precautions to Follow While Using

The use of an AED for onsite rescue is not always easy. Various unexpected situations will occur in the rescue process, so it is necessary to pay attention to the AED safety precautions while using.

 

  • If the patient is wet on the chest, dry with a cloth; otherwise, causing non-sticky AED pads to affect a precise heart rhythm analysis. • Remember not to use alcohol to dry the patient's chest, as alcohol is flammable.
  • If there are hairs on the chest, it is best to shave them off (ignore it if there is stray hair) as many chest hairs make AED pad difficult to completely fit the chest skin and be very hurtful when tearing off. Nevertheless, do not waste too much time shaving the chest, as shock delivery is the primary.
  • If there are metal objects on the chest, remove them; otherwise, they will conduct electricity when the machine sends an AED shock.
  • AED pads are placed differently for adults and children. For children under eight years of age, the disposable AED pads are placed on the front of the heart, and the other is placed on the back of the heart (anterior-posterior position).
  • Do not touch the patient or electrode wires while the device analyzes the heart rhythm; otherwise, the analysis will not be performed properly.• No one should be in close contact with the patient while the AED delivers a shock, as the current may travel from the patient to others.
  • When the AED machine indicates "shock not recommended", follow the device instructions and wait for emergency medical personnel to take over.

 

Place AEDs where necessary

Although the scene of police, firefighters, and EMS running to the site with AEDs is always visible, studies show that the fastest arrival time for EMS is around 7 minutes[3], which completely exceeds the optimal time for SCA. Furthermore, SCA occurs without warning, and you can never predict when, where and to whom it will happen, so having an AED device in places with a high incidence of SCA, such as gyms, stadiums, stations, airports, etc. can save valuable time and revive patients with ventricular fibrillation and ventricular tachycardia! After purchasing AED devices, it has to register the AED and actively participate in or conduct AED training to successfully implement the AED program.

Mindray AED for School
Mindray AED kit

If you are responsible for those areas that are not yet equipped with advanced life support equipment, then it is time to act quickly. The following are some tips for you to purchase public AEDs.

 

  1. Purchase AEDs approved by the Food and Drug Administration or have EU’s CE marking to ensure quality.
  2.  Buy public-friendly AED devices, which feature real-time and detailed voice and picture guidance and personalized feedback according to the user's operating proficiency.
  3. Go for an AED with a long shelf life; for example, AED replacement pads and batteries up to 5 years of shelf life can dramatically reduce subsequent maintenance costs.
  4. Choose AED equipment with biphasic 360J technology. Of course, it is not a must, but for those places that can foresee the presence of high-impedance patients, it is recommended to configure AEDs that can achieve 360J energy of electric shock to effectively improve survival rate of out-of-hospital cardiac arrests.
  5. Insist on a reliable AED supplier, for the follow-up service support and efficient equipment management and maintenance, because a reliable AED supplier will strictly control the quality of the product and be committed to technological innovation for a more comprehensive solution. 

As in the case of Mindray AED, has been deeply involved in the AED industry for more than a decade and mastered the advanced AED technology. The Mindray AED meet all the features mentioned above, including passing the CE certification and user-friendly patented ResQNaviTM technology to provide a personalized feedback mechanism for users. In addition, Mindray AED features biphasic 360J defibrillation technology, which effectively improves the survival rate of patients with different physical impedances. The 5-year warranty on the accessory makes it a highly cost-effective option for most buyers. Therefore, choosing a reliable AED manufacturer like Mindray is the guarantee for a successful implementation of your AED program.

 

AEDs offer an innovative way to save the lives of patients with SCA out of the hospital, making them no longer a dedicated device for EMS but rather a device that can be accessed by any person. For some public places that are not yet equipped with AED devices and have a high incidence of SCA, it is of great significance to pay attention to the AED device and purchase one from reliable AED manufacturers for the beginning of an AED program.

References:

 

[1] Consensus document regarding cardiovascular safety at sports arenas: Position stand from the European Association of Cardiovascular Prevention and Rehabilitation (EACPR), section of Sports Cardiology. European Heart Journal, Volume 32, Issue 17, September 2011, Pages 2119–2124. Available at: https://doi.org/10.1093/eurheartj/ehr178 (Accessed: 27 December 2021)

 

[2] Impact of Bystander Automated External Defibrillator Use on Survival and Functional Outcomes in Shockable Observed Public Cardiac Arrests. AHA Journal, Circulation. May 15, 2018, Vol 137, Issue 20. Pages 2104–2113. Available at: https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.117.030700 (Accessed: 27 December 2021)

 

[3] Emergency Medical Services Response Times in Rural, Suburban, and Urban Areas. JAMA Surg. October 2017, Volume 152. No. 10, Pages 983–984. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5831456/ (Accessed: 27 December 2021)