IN a previous article we discussed cardiac arrest and its importance. This week we will look at the measures that can be taken to try to improve the outcome in this common and morbid condition.

For most patients who suffer cardiac arrest the problem is that of cardiac arrhythmia. The vast majority of these are rapid heart rhythms that arise from the bottom chambers of the heart (ventricular tachycardia and ventricular fibrillation). These rhythms are amenable to what is known as defibrillation in which an electric current is sent through the heart muscle. This depolarises all the heart muscle at the same time and in most scenarios will lead to a normal heart rhythm. The ability to rapidly recognise and treat these abnormal heart rhythms is the major reason good outcomes can be obtained with cardiac arrest in the coronary care unit. In contrast, when these events occur outside of monitored health-care settings it is often not possible for defibrillation to take place within minutes resulting in a worsening of morbidity and risk of death. Decades of research have found that if blood flow to the heart and the brain can be sustained when the patient is in cardiac arrest, then the time window for successful defibrillation can be extended and the chance for successful outcome increased. This is accomplished by cardiopulmonary resuscitation or CPR which involves breathing for a patient and compressing the chest to support the delivery of blood and oxygen to the brain, the heart and other vital organs of the body. CPR is a skill which most lay persons can acquire quickly, for example, by doing a day course in basic life support.

In the United States, the American Heart Association (AHA) has developed programmes to try to improve the outcome of patients who suffer cardiac arrest. They have described what is known as the Chain of Survival where each link in this “chain” plays a significant role in decreasing mortality and morbidity. There are six parts to this chain:

1) Recognition of cardiac arrest and activation of the emergency response system.

2) Early cardiopulmonary resuscitation (CPR) with an emphasis on chest compressions.

3) Rapid defibrillation.

4) Advanced resuscitation by emergency medical services and other health-care providers.

5) Post-cardiac arrest care.

6) Recovery (including additional treatment, observation, rehabilitation, and psychological support).

It should be noted that the first three links in the chain of survival are dependent on educated and trained lay people who are able to deliver care in an emergency.

Recognition of cardiac arrest and activation of the emergency response system

From the perspective of identifying a cardiac arrest, an adult who is witnessed to collapse or who is found unresponsive needs to have an assessment of whether they are breathing spontaneously and whether they have a pulse. If a patient is without a pulse and not breathing, then the emergency medical services should be activated by calling 110 and CPR should begin. Checking for a pulse and the presence of spontaneous breathing is a skill that most adults can master. If as a bystander, you are unsure as to whether a pulse exists the safest approach to take is to commence CPR.

Early cardiopulmonary resuscitation (CPR) with an emphasis on chest compressions

It is important to note that the sooner that CPR begins after a patient is in cardiac arrest, the better the potential outcome. CPR allows for the resumption of blood flow to the heart and brain. This helps to keep the cells of these organs alive until the heart is restarted. It should be noted that for most bystanders who are not medically trained, CPR with chest compressions only that is, without rescue breathing is a reasonable course of action to take. This avoids the risk of exchange of body fluids with a person whose health status and medical history is unknown. Studies have shown that early in the CPR process enough oxygen remains in the blood stream so that similar outcomes are observed with traditional and compression only CPR.

Rapid defibrillation

Probably the most important link in the chain of survival is the rapid delivery of an electric shock to the muscle of the heart. Unfortunately, this requires the availability of an automatic external defibrillator (AEDs). These devices are different from the machines that we often see in medical dramas, in that they have pads which are attached to the chest and are much simpler to operate. A bystander need only turn the device on, attach the pads to the patient (usually following the diagram on the pads) and press a button to deliver the shock. Most of these devices made today have verbal instructions to guide use once they are turned on. Ideally these devices should be available in places where the public gather such as sports arenas, stadiums, schools, malls. The Heart Institute of the Caribbean (HIC) and HIC Foundation have been strong advocates for the acquisition of AEDs in public spaces.

After defibrillation care

The first three steps outlined above are the areas in which the lay public can act to improve the outcome in the cardiac arrest patient. Learning to recognise the patient in cardiac arrest and how to do CPR are skills that are easily acquired and the more people in our population who have these skills, the higher the chance that we give these patients to survive. The widespread availability of AED’s is important as well and we could look to our large corporations and government agencies to try and fill the void that currently exists. The remaining steps in the chain of survival are primarily the responsibility of the health-care sector and the Government. There is a need for a properly equipped, trained, and maintained emergency medical service who can service as much of our island as possible. These personnel provide advanced resuscitation techniques to support the patient beyond simple defibrillation. These techniques include obtaining and maintaining an airway for breathing, starting IVs, giving drugs, obtaining electrocardiograms, etc. In many countries the emergency medical services are in communication with emergency rooms so that physician input can be obtained prior to the patient reaching the hospital.

Post-arrest cardiac care is a large topic that is beyond the scope of this article. Suffice it to say that every society needs facilities like HIC that can quickly and comprehensively manage critically ill patients with severe cardiac disease. Otherwise, the initial gains with successful CPR are lost. There is often a need for assessment of cardiac function, of the blood flow to the heart muscle, management in a cardiac intensive care unit, mechanical ventilation, introduction of techniques that have been shown to improve outcome such as hypothermia and physicians with expertise in protecting the brain and other organs after cardiac arrest. Lastly for patients that survive and leave the hospital, there is often the need for rehabilitation and long-term care.

Improving outcome in patients with cardiac arrest requires input from many segments of the society. For the lay population, the larger the percentage of the population that can provide basic life support the more likely it is that a patient who has a cardiac arrest can be assisted. It may help to think selfishly about this issue as the person that you aid may be a family member or a friend. Our entire health care system, public and private, have roles to play including continuing education of both the professional class and lay public about this critical issue, providing training in basic life support and laying the groundwork for post-cardiac arrest care.

Of importance is the diagnosis and treatment of patients who have heart disease that puts them at risk for cardiac arrest. Often medical treatment, surgical or percutaneous procedures or implantation of implantable cardiac defibrillators will reduce risk in these patients. Corporate Jamaica and our large State agencies should ensure that the public spaces that they manage have AEDs available and clear directions on where to find and access these devices. Our Government and Ministry of Health should play a key role in ensuring facilitated recruitment of qualified and experienced health-care workers from the global marketplace, especially in the post-COVID era when countries around the world are aggressively recruiting talent from Jamaica and elsewhere to protect the lives of their citizens. A policy and regulatory framework from the Ministry of Health will provide guidance and direction to other agencies and parastatals to ensure that they embrace a common purpose and the noble ‘One Health’ initiative that has been championed by the Minister of Health Dr Christopher Tufton. This will create the enabling environment to facilitate efforts in reducing the scourge that is sudden cardiac death.

While it is not likely that we can improve the outcome of patients with out of hospital cardiac arrest to the level of a patient who has an arrest in a monitored health-care setting, there is the opportunity to significantly change the chance of survival of these patients especially if we have facilities with appropriate infrastructure and necessary human capital to provide post cardiac arrest care.

Dr Ernest Madu, MD, FACC and Dr Paul Edwards, MD, FACC are consultant cardiologists for Heart Institute of the Caribbean (HIC) and HIC Heart Hospital. HIC is the regional centre of excellence for cardiovascular care in the English-speaking Caribbean and has pioneered a transformation in the way cardiovascular care is delivered in the region. HIC Heart Hospital is registered by the Ministry of Health and Wellness and is the only heart hospital in Jamaica. Correspondence to info@caribbeanheart.com or call 876-906-2107