A shock to the heart

The shock of your life…

Sometimes a shock to the system can save your life. Defibrillators, the devices that doctors apply to the chest of people in cardiac arrest in order to shock the heart into beating properly, have saved many lives since they were first invented. The electrical device, which has become familiar to everyone through its perennial use in hospital dramas such as 'ER', could save many more lives if it where more widely available however.

Many people are not aware that heart attacks, or myocardial infarctions to give them their proper name, fall into a number of categories. The most common type of cardiac arrest is known as ventricular fibrillation, because it involves the ventricles, or lower chambers of the heart, going into spasm.

These uncoordinated contractions usually return to a regular heartbeat but in some circumstances this does not occur. When the heart remains in spasm, it ceases to pump blood around the body, which quickly leads to the victim falling unconscious. This is a dangerous state for anyone to be in, as it can lead to clinical death within a matter of minutes.

Motorcycle ambulances

The Eastern Regional Health Authority has three motorcycle ambulances operating already each with a defibrillator and depending on the outcome of a recent study, it may introduce more.

It is essential to get the heart pumping oxygenated blood around the body as quickly as possible in this situation and every second counts. It is equally important that the heart's electrical system is restored to its proper activity. The most effective way of achieving both of these at once is to defibrillate.

A defibrillator - designed to give you the shock of your life.

According to the American Heart Association, with each passing minute that a person is in cardiac arrest, their chance of survival falls by a further 10%. In other words, after five minutes, there is only a 50/50 chance of living through the heart attack. Even if the victim survives the attack, if their brain is starved of oxygen for more than a few minutes they will probably suffer brain damage. For these reasons especially, early intervention is vital to save lives.

"The faster you can provide basic defibrillation to a patient who has suffered cardiac arrest, the better their chances are of survival", explains Drew Hofmann, whose company in Belfast makes simplified portable defibrillators for use in public places.

"Every minute that you wait causes deterioration of the heart muscle, which makes it harder for the person to survive. Our idea is to put defibrillators out in areas where they are accessible to the public".

Public access

Hofmann's company already supplies defibrillators to all kinds of organisations that one would not normally associate with purchasing hi-tech medical equipment. In America, the Clinton administration introduced legislation requiring all federal buildings to have a public defibrillator and many private organisations have followed the federal lead.

Since the Australian airline Qantas first took a defibrillator onto a plane, nearly every major long-haul airline has followed suit and flown with one. Drew Hofmann believes that it is only a matter of time before defibrillation is considered in the same light as CPR or other aspects of first aid.

"Most people who are now trained in CPR will in future have defibrillation training", he believes. "They will know where the machine is and how it works. It is only a little extra training beyond CPR. When a defibrillator is needed it is usually a panic situation, so people trained to use the machine need to be able to handle that. Otherwise, all they need to do is simply place the two pads where the machine tells them to. They don't have to do anything else except press the button".

"That doesn't mean that anyone could just walk up and grab it and defibrillate somebody unless they were trained", he says. "The training helps non-medical people to know what should be done in an emergency. Knowing how to use a defibrillator goes along with contacting the emergency services and using CPR where appropriate".

On television shows, the doctor shouts 'Clear!' and the patient jumps around in shock, but the energies used are actually much lower now than anything displayed on 'Casualty' or 'ER'. Anyone using a defibrillator is unlikely see a patient jump these days. Most machines will shock in the range of 100-200 joules, which is a relatively low electrical jolt to the body.

Drew Hofmann, flanked by two of the men who helped to design the portable defibrillator his firm builds in Belfast - cardiologist Professor John Anderson (l) and engineer Andrew O'Hara (r).

The idea to take defibrillators out of the cardiac wards and onto the streets is not a new one, but only in the last few years has technology allowed for small, mobile and easy-to-use machines to be manufactured. Defibrillation had been a target for medical researchers since the late 19th century, when it was first suspected that ventricular fibrillation was causing sudden deaths. In 1947 an American surgeon called Claude Beck first managed to defibrillate the human heart. After six unsuccessful attempts, he managed to restore the heartbeat of his seventh patient.

Pioneers in Belfast

Belfast is considered by experts to be where mobile defibrillators were first invented. A cardiologist from the Royal Victoria hospital, Dr Frank Pantridge is credited with inventing not only the first defibrillator that could be moved from place to place, but also with coming up with the idea of the first cardiac ambulance. Before Pantridge, defibrillators used to be huge bulky devices that had enormous capacitors inside to store all the energy they required.

"Dr Pantridge was the very first to have the idea of mobile coronary care", explains Drew Hofmann. "He wanted to take the technology and put it in an ambulance. Professor John Anderson who worked alongside him designed the very first defibrillator to take onto the street. It was enormous and ran off great car batteries. They published their research and are acknowledged as the first people to come up with the concept. Over the years they designed a range of defibrillators called the Pantridge defibrillators which were very different to the rest of the technology available".

The Belfast team's concept is now saving lives all over the world, although like the best of prophets, their insights have been largely ignored at home. Only in January of this year did Mountbellew in County Galway become the first town in Ireland to receive a public-use defibrillator.

Nearly 30 of the town's citizens received 40 hours of training in the use of emergency medical equipment, including defibrillators as part of a Community Action in Response to Emergencies (CARE) scheme. The Western Health Board introduced the scheme at the request of local GPs, since the town is over 30 minutes away from the nearest ambulance service. According to the WHB, this scheme is expected to be spread to other remote parts of the West and South-West in time.


Time, however, is not something that people at risk of a heart attack have to spare. With this in mind, the Northern Ireland Chest, Heart and Stroke Association (NICHSA) has launched a concerted campaign to have public defibrillators in every place where large numbers of the public gather.

According to Andrew Dougal of the NICHSA, public access defibrillators should be introduced to every airport, golf course, shopping centre, sports ground, workplace, ferry port and train station.

"The beauty of these devices is that they can be used by anyone with the minimum of training", he says. "The machines are so sophisticated that they can decide for themselves if an electric shock is needed to restart the heart. If a shock is not needed, it will not apply one. I am convinced these machines will increase survival rates, by reducing the interval between collapse and the first defibrillation".

An internal defibrillator is implanted into the chest like a pacemaker and helps to maintain a proper heartbeat.

The idea of placing a complex piece of medical equipment in public spaces as if it were a fire extinguisher is a novel one to many, but with such high mortality rates in Ireland because of cardiovascular disease, it seems essential that we consider following the American example in Ireland.

The Department of Health told irishhealth.com that there were no formal plans to publicly fund defibrillators outside of the health service except in cases such as the Mountbellew CARE group.

But private organisations are increasingly likely to purchase defibrillators when they understand that these machines can save the lives of their employees, their clients and any visitor who happens to be on their premises.

Legislation along the US lines to compel public buildings to have defibrillators may be some way off here in Ireland, but as more and more people understand that this Irish technology is saving lives elsewhere, they may start demanding to see Irish people given the same protection should they suffer a heart attack.

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