What is a defibrillator?

What is cardiac arrest?

Cardiac arrest is a serious medical emergency that occurs when the heart's electrical system experiences a disruption, causing the heart to stop pumping blood. As a result, the patient may lose consciousness, become unresponsive, and stop breathing. A heart attack or an inherited heart condition are common causes of the disruption. In both cases, the electrical system in the heart stops working as it should, resulting in ventricular fibrillation, a life-threatening heart rhythm.

During ventricular fibrillation, the heart's electrical system fails to beat regularly and pump blood around the body, causing the patient to collapse. Chest compressions can assume the heart's function to keep blood circulating throughout the body and to maintain brain function. Rescue breaths ensure that oxygen continues to enter the blood through the lungs. The use of a defibrillator is also crucial in treating cardiac arrest.

How to do CPR

When you encounter someone unconscious, performing CPR quickly and accurately is critical. The British Heart Foundation has developed a step-by-step plan to assist with CPR.

What is a defibrillator, and how does it work?

Emergency medical services in the UK respond to over 30,000 out-of-hospital cardiac arrests (OHCA) each year, but unfortunately, the survival rate is alarmingly low. Less than 1 in 10 people in the UK survive an OHCA. The low survival rate highlights the critical need for early intervention, including defibrillators, to improve the chances of survival in such emergencies.

An Automated External Defibrillator (AED) is a portable device designed to deliver an electric shock in case of cardiac arrest. The defibrillator's electric shock can restore the heart's normal rhythm, allowing the heart chambers to pump blood effectively once again. Chest compressions and rescue breaths are not enough to reset the heart, and using a defibrillator in combination with quality CPR significantly increases the patient's chance of survival. Defibrillators are often available in public places such as airports and shopping centres and can be used by anyone, regardless of their level of training. 

Importance of attaching a defibrillator in resuscitation efforts

It is advisable to retrieve and attach a defibrillator, regardless of whether you think the heart is still functioning. The situation can quickly change, and CPR may become necessary. The defibrillator's heart rhythm analysis can provide a definitive answer as to whether a shockable rhythm is present. The defibrillator is designed to guide you through the resuscitation process with step-by-step instructions. You do not have to be a professional rescuer to operate a defibrillator! 

Benefits of having a defibrillator 

Having a defibrillator on hand can be a lifesaver, literally. Studies have shown that using a defibrillator within the first few minutes of cardiac arrest can significantly increase a person's chance of survival. For every minute that passes without defibrillation, the chance of survival decreases by 7-10%. In addition to saving lives, having a defibrillator on hand can also provide peace of mind for businesses and individuals. Sudden cardiac arrest can happen to anyone, anywhere, at any time, and without warning. Knowing that you have a defibrillator nearby can help you feel prepared.

How to use a defibrillator 

Despite their life-saving potential, using a defibrillator can still seem intimidating to some people. But by following these simple steps, you can help improve the chances of survival for someone experiencing cardiac arrest:

1. Turn on the defibrillator and follow the voice or visual prompts provided.

2. Call the emergency services

3. Shave any chest hair and remove undergarments if necessary.

4. Attach the electrode pads to the patient's chest and stand clear. 

5. Press the shock button immediately if prompted by the defibrillator (fully automatic defibrillators will automatically deliver the shock if required).

6. If the patient is still not responsive, continue chest compressions and follow the instructions of the defibrillator until emergency services arrive.

When and how does the defibrillator deliver a shock?

The defibrillator guides rescuers through the resuscitation process and indicates whether to continue CPR or deliver a shock. It gives a shock command only if it detects a shockable heart rhythm, such as ventricular fibrillation (VF) or ventricular tachycardia (VT), which indicates that the heart cannot efficiently circulate blood. The defibrillator can help restore the heart's rhythm with a shock. If a shock is advised, the defibrillator will either administer the shock itself (in the case of a fully automatic defibrillator) or prompt the rescuer to press the shock button (in the case of a semi-automatic defibrillator). Once the defibrillator has delivered the shock, the device will notify the rescuer and chest compressions and rescue breaths should be immediately resumed until the defibrillator begins to analyse the heart rhythm again. The defibrillator will only deliver a shock when necessary and safe to do so. It is impossible to administer the shock without the defibrillator detecting the need for one.

When does the defibrillator not deliver a shock?

It can happen that the defibrillator does not give a shock command after the cardiac rhythm analysis. 

There are several situations in which this can occur: situations without a shockable heart rhythm.

• When someone is unconscious but not in cardiac arrest. The heart is still functioning.
• When there is no heart activity at all. The victim has already passed away.

If the defibrillator does not deliver a shock, do not stop performing CPR yet. Follow the instructions provided by the defibrillator. CPR ensures the circulation of oxygen-rich blood and is crucial for vital organs. Regardless, keep performing CPR until medical assistance arrives.

Types of defibrillators

Semi-automatic and fully automatic defibrillators are types of defibrillators used to deliver a shock to the heart in case of cardiac arrest. A semi-automatic defibrillator requires the operator to press a button after attaching the electrode pads to the patient's chest. A fully automatic defibrillator delivers the shock automatically after analysing the patient's heart rhythm. The fully automatic provides a more hands-free approach, making it quicker in situations where every second counts. Both are user-friendly and equipped with voice prompts and sometimes visual instructions to guide the operator. 

Product selection

After reading the above information, you may be interested in providing a defibrillator for your company, organisation, or personal use. However, with the variety of defibrillators available in the market, it can be challenging to choose the right one. Consider the following factors when selecting a defibrillator that suits your situation:

• Purpose: Determine the intended use of the defibrillator, whether it is for a public area, healthcare facility, or personal use.
• Type: Choose a semi-automatic or fully automatic defibrillator, depending on your preference and training level.
• Features: Look for features such as voice prompts, visual instructions, CPR feedback, and long battery life.
• Price: Consider the budget available and compare prices from different manufacturers.

At AEDexpert.co.uk, we offer a wide selection of defibrillators to meet every need. Our selection includes defibrillators from brands such as Philips, Zoll, and Physio-Control. To help make an informed decision, we've created a comparison chart that outlines the features and benefits of each defibrillator model we offer. If you have any further questions, do not hesitate to contact customer service at +44 (0) 1223 790124 or [email protected].