Why defibrillators work

Several types of defibrillators exist, varying in application. Manual defibrillators—the ones that likely come to mind for most laypeople—require professional training to use properly. Using an electrocardiogram built-in or separate , the operator diagnoses the heart rhythm present and, if a potentially fatal arrhythmia is found, manually sets the voltage and duration of the shock before applying the electrodes. Conductive gel is also applied manually before use.

Paddle electrodes exist almost exclusively on manual external defibrillators used in hospital settings, often with disposable conductive gel pads. With training, the paddles can be placed and activated quickly, saving precious time in a procedure where every second means further tissue damage. Because of this, AEDs are most useful for out-of-hospital cardiac arrests. Internal defibrillators also exist for extremely high-risk patients.

In some cases, manual internal defibrillators may be used during an open-heart procedure in the operating room or emergency room. Implantable cardioverter-defibrillators are surgically applied similarly to artificial pacemakers and, like AEDs, are programmed to monitor heart rhythms and detect when intervention is necessary to treat arrhythmia. Training programs for first aid often include instruction on the use of AEDs alongside CPR and other procedures, for those who want hands-on practice.

TV shows and movies are ill-equipped to demonstrate correct defibrillator use and often exaggerate their effectiveness. While defibrillators are invaluable in saving the lives of patients suffering from cardiac arrest, reckless use—or failing to use one when needed—can instead endanger lives.

Some people fail to act when sudden cardiac arrest occurs in public because they believe that medical training is needed to use a defibrillator and misusing one can instead lead to patient death. AEDs, however, circumvent both issues.

If an AED is available, do not wait for professionals to arrive before acting. CPR is just as important as defibrillation in the event of sudden cardiac arrest.

Chest compressions can help manually pump blood to deliver oxygen supplied by rescue breathing. This helps to delay tissue death until defibrillation begins, or emergency providers arrive. Hundreds of people are alive today entirely due to the prompt and appropriate use of a defibrillator. Once activated, the AED will talk to you and tell you what to do:. Check for: Danger: Do not put yourself in danger Response: If no response shout for help and if possible, get a bystander to call for an ambulance and locate a defibrillator if there is one.

Airway: Open the airway and check for breathing. If you have help: Get your bystander to let the emergency services know that the casualty is unconscious and not breathing.

Meanwhile, you should bring the AED as quickly as possible. Continue CPR whilst waiting for the defibrillator. To give effective CPR : push down cms on the centre of the chest at a rate of about 2 compressions per second and ensure a release from pressure in between compressions, to enable the heart to refill. Give 30 compressions to 2 breaths.

Defibrillators are designed to be as easy as possible to use. Firstly, activate it. Machines vary but this is usually done by opening the lid or pressing an obvious button. Dry the chest and use the razor to shave if excessively hairy. Peel the pad off the backing one at a time and place onto the dry chest according to the diagram on the packet. The AED will analyse the heart rhythm.

Ensure no one is touching the casualty. Check the whole length of the casualty to ensure no one is touching them. Press the flashing shock button as directed fully automated AEDs will do this automatically once a shock is advised.

Continue with CPR as directed. Keep going with 30 compressions to 2 breaths. Do not stop to check them unless they begin to regain consciousness and start breathing normally. The machine will reassess their heart rhythm every 2 minutes and advise another shock if indicated. Stop CPR if the casualty begins to regain consciousness and starts to breathe normally.

However, we need far more in the community and work-places to be able to have the major improvements on survival from cardiac arrest that is seen in other countries such as Sweden.

Unfortunately there are many common misconceptions about defibrillators that prevent people from incorporating them in their mainstream first aid equipment:. Furthermore, they are now available in so many public places and are easily accessible for the general public to grab and use as quickly as possible in a medical emergency. Additionally, you do not need specific training to use them.

They are available for use by the general public. Ideally you would have received training in how to give the best CPR as this will make a huge difference and give them the best possible chance of survival. Using an AED is simple. You cannot use a defibrillator if the casualty does not need it! It will not let you. Sadly, this is not the case.

There are many reasons why someone may experience a sudden cardiac arrest and it is not possible to resuscitate everyone. However, good quality CPR, prompt use of a defibrillator and swift transfer to professional medical care, will give them the best possible chance. Definitely not the case.

The sooner you use the defibrillator the better their chances of survival. If a child is unconscious and not breathing, you should use a defibrillator as quickly as possible in the same way as you would with an adult. For a child you start with 5 rescue breaths. It is essential to be giving effective CPR alongside using the defibrillator. CPR circulates blood to the heart and brain. Without quality CPR it is highly unlikely the casualty will survive. I am afraid that this is highly unlikely as our emergency services are hugely overstretched and they are not likely to be with you within 3 minutes.

First Aid for Life provide award-winning first aid training tailored to your needs. Please visit our site and learn more about our practical and online courses.

It is vital to keep your skills current and refreshed. We are currently providing essential training for individuals and groups across the UK. In addition, we have a great range of online courses. These are ideal as refreshers for regulated qualifications or as Appointed Person qualifications. You can attend a fully regulated Practical or Online First Aid course to understand what to do in a medical emergency.

First Aid for Life is a multi-award-winning, fully regulated first aid training provider. Our trainers are highly experienced medical, health and emergency services professionals who will tailor the training to your needs. Courses for groups or individuals at our venue or yours. First Aid for life provides this information for guidance and it is not in any way a substitute for medical advice. We are not responsible or liable for any diagnosis made, or actions taken on this information.

Dear Marie, I am afraid you have been wrongly advised. If you see that someone has fainted and suspect that he or she may need an AED :. The home AED comes with an instructional training video that shows how to use and maintain the device.

If you buy an AED , everyone in your home should watch the video and review it periodically. Police and ambulance crews carry AEDs , and they're commonly available in many public places, including malls, office buildings, sports arenas, gyms and airplanes.

However, many cardiac arrests occur at home, so having a home AED can save precious minutes in reviving a person with ventricular fibrillation and ventricular tachycardia. Proponents of home AEDs say putting them where they're needed most will save many lives. But critics argue there's no reliable evidence that home defibrillators save more lives. For some people who have a high risk of cardiac arrest, having an AED can provide peace of mind and might help save their lives. Here are some things to keep in mind as you consider whether to buy an automated external defibrillator:.

If you get an AED for your home, make sure that family, friends and visitors know where it is and how to use it. And you need to maintain it properly. Here are some tips for buying and maintaining your home AED :. AEDs offer a way to save a life. Before buying one, talk to your doctor and do research. And don't forget to learn the basics, such as CPR. There is a problem with information submitted for this request. Sign up for free, and stay up-to-date on research advancements, health tips and current health topics, like COVID, plus expert advice on managing your health.

Error Email field is required. Error Include a valid email address. To provide you with the most relevant and helpful information and to understand which information is beneficial, we may combine your e-mail and website usage information with other information we have about you. The image compares an ICD with a pacemaker. Figure A shows the location and general size of an ICD in the upper chest. The wires with electrodes on the ends are inserted into the heart through a vein in the upper chest.

Figure B shows the location and general size of a pacemaker in the upper chest. How do WCDs work? Who Needs Them? Who needs an AED? Who needs an ICD? If you have the following conditions, you may be at risk for a life-threatening arrhythmia and your doctor may recommend an ICD: You survived sudden cardiac arrest.

You developed an arrhythmia during or after treatment for a heart attack. You have a genetic condition that causes arrhythmia. This includes having congenital heart disease or an inherited conduction disorder.

You have a neuromuscular disorder. For example, the progression of muscular dystrophy can damage the heart and cause unpredictable heart rhythms.

This can lead to unexplained fainting and a high risk of death. You have cardiac sarcoidosis. You have poor heart function following a procedure to improve blood flow. Your doctor detected an arrhythmia during an electrocardiogram EKG or stress test.

If this happened several times, you may be at increased risk. Who needs a WCD? This might occur under these conditions: You are recovering from a heart attack. You are waiting for a heart transplant. You are fighting an infection. You are removing or waiting to replace your ICD. When to use an AED. If you think someone may be in cardiac arrest, try the following steps: If you see a person faint or if you find a person already unconscious, first confirm that the person cannot respond.

The person may not move, or his or her movements may look like a seizure. You can shout at or gently shake the person to make sure he or she is not sleeping, but never shake an infant or young child.

Instead, you can gently pinch the child to try to wake him or her up. If the person is not breathing and has no pulse or has an irregular heartbeat, prepare to use the AED as soon as possible. Where to find an AED. How to use an AED. When using an AED: Call or have someone else call If an electric pulse or shock is needed to restore a normal rhythm, the AED uses voice prompts to tell you when and how to give the shock, and electrodes deliver it.

Some AEDs can deliver more than one shock with increasing energy. The device may instruct you to start CPR again after delivering the shock. Surgery for ICDs - Defibrillators. Before and during surgery. Recovery from surgery. Follow the instructions you receive. Your healthcare team may tell you to take these steps: Check the cut on your chest often and keep the area clean and dry. Call your doctor if any swelling or bleeding occurs or if you develop a fever.

Take over-the-counter pain medicines such as acetaminophen if you feel pain. But talk to your doctor first; he or she may tell you to avoid taking ibuprofen or other kinds of pain medicines, for example. Ask your doctor when you can resume taking medicines that you took before the surgery, how soon you can take a shower, and when you can return to work. You will probably have to avoid driving for at least a week while you recover from your surgery.

Your doctor may also ask you to avoid high-impact activities and heavy lifting for about a month. Possible surgery-related complications. Although they are rare, possible complications include: A bad reaction to the medicine used to make you relax or sleep during the surgery A collapsed lung A defibrillator wire puncturing the heart or a vessel Bleeding from the site where the device was placed Blood vessel, heart, or nerve damage Swelling, bruising, or infection at the area where the device was placed Venous thromboembolism Some ICD models have a lower risk of clots, puncture, and infection.

Look for. Living With to learn more about your recovery and life after you return home. Research for Your Health will explain how we are using current research and advancing research on defibrillators. Living With - Defibrillators. What to expect from electric shocks. Low-energy shocks. The low-energy electrical shocks your device gives are not painful. You may not notice them, or you may feel a fluttering in your chest. High-energy shocks. The high-energy shocks last only a fraction of a second, but they can be strong or painful.

They may feel like thumping or a kick in the chest, depending on their strength. Before a shock, you may feel arrhythmia symptoms.

If you feel one or two strong shocks over a short period and the symptoms go away, it may be a sign that the device is working. He or she will want to assess your condition and the device. Unnecessary shocks. During the adjustment period after your surgery, your device may deliver a shock when it is not needed. A damaged wire or a very fast heart rate due to extreme physical activity may trigger unnecessary shocks.

These shocks can also occur if you forget to take your medicines. Some people also feel phantom shocks, even when the device does not detect an arrhythmia.

Make sure your WCD is fitted properly. Return to normal daily activities. Physical activity. An ICD usually will not limit you from taking part in sports and exercise, including strenuous activities. You may need to avoid full-contact sports, such as football. Contact sports can damage your ICD or shake loose the wires in your heart. Ask your doctor how much and what types of physical activity are safe for you.