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How do defibrillators work

The many TV shows and films over the years have portrayed defibrillators as a device to be used mainly by trained professionals, a device that is dangerous to use, quite often depicted with a medical team surrounding a patient, rubbing two large paddles together before applying a patient to deliver a shock.

It’s quite understandable why for many, this is what a defibrillator is, this is what it looks like, and often the first thing that comes to mind when someone thinks of a defibrillator. TV and film have helped shape our perception, and potential apprehension or fear about using a defibrillator.

Many of the Public Access Defibrillators available in Australia today are designed to be very easy to use, even for the untrained user. As a sudden cardiac arrest can occur anywhere at any time, having access to a defibrillator that anyone can pick up and use in an emergency, which provides clear step by step instructions that are easy to follow will greatly assist with providing critical care to the patient. Simply apply the pads to the patient, and follow the prompts.

Automated External Defibrillators designed for public use are lightweight, portable, with clear visual and audible aids, and are used by individuals, organisations, and many medical and emergency service types of organisations throughout Australia.

What is a defibrillator used for

A defibrillator helps provide patients with heart disease an increased fighting chance when a sudden cardiac arrest occurs. In Australia, approximately 30,000 people suffer from a cardiac arrest, and if this occurs outside of a hospital environment, there is approximately a 1 in 10 chance of survival. Having a defibrillator nearby, can greatly assist in the chance of survival in an emergency.

When a sudden cardiac arrest occurs, the heart can suddenly stop pumping. Defibrillators can restore the normal heartbeat by carrying out an electric shock or pulse to the heart. A defibrillator can also assist in preventing arrhythmias which are characterised by having a heartbeat that is too slow or too fast.

A defibrillator can be used when a patient is unresponsive, or is not breathing normally, and CPR is required. By placing the defibrillator pads on a patient, the defibrillator will analyse the patient to determine if a shock is required. If required it will advise the rescuer through audible and visible indicators or prompts that a shock is required, and when to commence and conclude CPR.

If a shock is not required, the defibrillator will also advise the rescuer that a shock is not required. The public access defibrillators on the market provide a great amount of assistance to the would-be rescuer, to help reduce the stress and anxiety in an emergency, even for an untrained user.

How often should defibrillators be checked

Public access defibrillators are designed with ease of use in mind, and minimal maintenance. The question of how often should defibrillators be checked comes up from time to time, and the process to check a defibrillator is straight forward.

A very handy feature is that defibrillators run automatic self-checks. These can be daily or weekly depending on the brand and model. A defibrillator checks to ensure it is in working order, and consumables such as batteries and pads are not expired.

If there is an issue, the defibrillator requires attention, the battery and pads are expired, or nearing expiry, a defibrillator will usually beep to alert the user to inspect the defib. Where there is a visual indicator such as a green light, or a symbol, that green light will usually change to red, and the symbol will change to an alert type of symbol. Some brands will sound an audibly spoken alert to the user to replace battery or replace pads.

Defibrillators that are Wi-Fi compatible and connected to a Wi-Fi network with a user registered as a contact, the user may receive an automated email communication to alert them the defibrillator requires inspection, or that the device has been used in an emergency.

As a defibrillator is an essential device to be in working order when needed, implementing a schedule of inspecting the defibrillator is highly recommended. This can range from each month to every 3 months and will only take a few moments of your time.

Common checks:

· Visually inspect that the defibrillator indicator light is on, and showing the correct status (green in many cases)

· Power the defibrillator on and off, to make sure it is turning on correctly

· Check the expiry dates on the battery and pads to ensure they are current (if nearing expiry, organise or schedule a date for them to be replaced)

· Ensure that the defibrillator is accessible, and its location (e.g., a staff member hasn’t moved it to another area of the building, and has not returned it to its normal location)

As you can see, the process to inspect a defibrillator is very straight forward and doesn’t require a lot of your time. Having a process in place to regularly inspect your defibrillator will also provide additional peace of mind.

Businesses, workplaces, and sports clubs which use a First Aid organisation to provide routine or scheduled maintenance of their First Aid Kits, it is highly recommended that inspection of the defibrillator is added to their maintenance checklist.

How long do defibrillators last

The leading brands of defibrillators in our range such as HeartSine, Lifepak, Philips HeartStart and Zoll feature a long warranty period, up to 8 years for many of the models. The long warranty period is important as it provides confidence in the reliability and durability of the brand.

Aside for the warranty aspect of the hardware, the consumables such as batteries and pads have an expiry date on them and need to be current to ensure the defibrillator is ready to use when needed. Batteries can last for up to 4-5 years, and pads from 2-5 years before they need replacing. Pads will need to be replaced when used.

For example, a new battery can delivery up to the following duration and number of shocks:

· Heartsine 350p, 360p or 500p – 4 years or up to 60 shocks

· HeartStart HS1 or Frx – 4 years or up to 200 shocks

· LIFEPAK CR2 – 4 years or up to 166 shocks

· ZOLL AED Plus – 5 years or up to 225 shocks

· ZOLL AED 3 – 5 years or up to 140 shocks

Whilst the warranty of a defibrillator set by the manufacturer is a good indication of how long do defibrillators last, like many other electronic devices, it is not uncommon for them to last well beyond their warranty period in many instances.

It is recommended after the warranty period expires to review what else is on the market at that future point in time, to see and compare what other key features and technological developments may have occurred in the defibrillator space, such as new features, size or even price.

To see more detail about the features, battery, and pad life of the defibrillators we range, feel free to download the product brochures, or view the various demonstration videos hosted on our ‘Resources Page’.

If you are wanting to find out more, or discuss the various models, please feel free to contact us, we are here to help.

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