Sudden Cardiac Arrest and Primary First Aid Treatment

The chance of surviving a sudden cardiac arrest is largely dependent on immediate medical care, so keep reading as it could help you save a life one day in the future.

Defining sudden cardiac arrest

Sudden cardiac arrest occurs when the heart stops pumping blood to the body and brain. It usually occurs when the electrical impulses in the heart become rapid or chaotic, and the heart beats so fast it quivers instead of pumping blood throughout the body. Sometimes a cardiac arrest can occur due to extreme slowing of the heart.

The sudden cessation of blood flow and loss of oxygen to the brain causes unconsciousness and breathing to stop. Untreated, it can lead to brain injury then death within four to six minutes.

Symptoms of cardiac arrest

Sometimes sudden cardiac arrest is preceded by a racing heart beat or feeling dizzy. Other signs may include blackouts, shortness of breath, chest pain or fainting, but often there is no warning, and a victim of cardiac arrest can lose consciousness before they can ask for help.

The symptoms of sudden cardiac arrest are very major:

• Sudden collapse 

• Unconsciousness

• No breathing

• No pulse

Because blood is not being pumped there is a lack of circulation and therefore no carotid pulse.

Causes of cardiac arrest

Sudden cardiac arrest is most likely to occur in people with underlying heart problems, especially those with coronary artery disease. The immediate cause of sudden cardiac arrest is caused by an electrical problem in the heart, when the electrical pulses through the heart result in it beating too fast, too slow, or irregularly.

This is known as arrhythmia.

A sustained arrhythmia is unlikely to develop in a person with a healthy heart unless there is trigger such as an electric shock, drug abuse or chest trauma. However, if there is a pre-existing heart condition then it is much more likely that a life-threatening arrhythmia may develop.

There are several types of heart conditions that can put people are risk including an enlarged heart, valvular heart disease and congenital heart disease, but the major one is coronary heart disease. With coronary heart disease the coronary arteries are narrowed by fatty buildups of cholesterol and other deposits. This reduces the blood flow to the heart which can reduce its ability to conduct the electrical impulses. Severe coronary artery disease can then lead to a heart attack which results in an area of dead tissue in the heart which can then cause further electrical short circuits. Over 80 per cent of sudden cardiac arrest victims have coronary artery disease.

People most at risk for sudden cardiac arrest are:

• Those with coronary artery disease 

• People who have had a heart attack

• Those who have previously survived a sudden cardiac arrest

• People with a family history of sudden cardiac arrest

• Those with primary heart rhythm abnormalities

Causes not related to existing heart conditions can include overdoses, traumas, infections and cancer.

Out of hospital treatment

Unless appropriate medical care is given immediately, sudden cardiac arrest is fatal. The chances of survival are vastly improved if cardiopulmonary resuscitation (CPR) is administered, as this can keep blood flowing to vital organs and prevent brain death. Several organizations, including the American Heart Association, promote a “chain of survival” which has the following steps.

• Early recognition

• Early CPR

• Early defibrillation

• Early advanced care

Early recognition is a key to survival, as a person’s chance of survival drops by around 10% for every minute they are in cardiac arrest.  If someone falls unconscious and you suspect a possible cardiac arrest then dial for an ambulance immediately and commence CPR.

Early CPR is important because it can double or triple a cardiac arrest victims chance of survival. If you don’t know how to do CPR then administering rapid compressions to the chest will improve the chance of survival until medical help arrives as the lack of oxygenated blood to the brain can cause damage within only a few minutes. If an unconscious person is breathing then it is unlikely they have had a cardiac arrest, but if they are not breathing then push hard and fast on their chest at a rate of around 100 compressions per minute until they are either breathing or help arrives. Now would be a good time to learn CPR and if you don’t want to take a class then there are plenty of resources on the web to teach the correct way to give rescue breaths.

Early defibrillation has been proven to be an effective treatment. A defibrillator delivers an electric shock to get the heart back into a normal rhythm. The shock will normally be given by the emergency personnel, but an increasing number of public places have them available, and an emergency medical operator can instruct you how to use it over the phone while waiting for an ambulance.

Early advanced care is the fourth and final step and usually involves Life Support.

Hospital treatment

Once the patient arrives at the hospital various treatments may be given to stabilize them, including defibrillation, drugs and CPR. Some people may be in a coma and some may only recover partially and have impaired brain function. Sometimes a doctor will induce hypothermia as this has been shown to improve the recovery outcome.

Following stabilization there are a range of long-term options including

• Using anti-arrhythmic drugs

• Impalnting an implantable cardioverter defibrillator (ICD)

• Coronary bypass surgery

• Coronary angioplasty

• Heart surgery

• Heart transplant 

The choice of options will require several tests to determine what is right for each individual person.

How to prevent sudden cardiac arrest

As always, prevention is better than cure. Preventing sudden cardiac arrest (SCA) is largely about adopting a heart-healthy lifestyle combined with regular medical monitoring. This means eating a balanced diet rich in fruits, vegetables, and whole grains, while limiting unhealthy fats, sodium, and sugars.

Engaging in regular physical activity, such as 150 minutes of moderate aerobic exercise weekly, is crucial for maintaining a healthy heart and weight. Managing cardiovascular risk factors like high blood pressure, cholesterol levels, and diabetes through both lifestyle changes and medications as prescribed is essential. Additionally, avoiding smoking and moderating alcohol consumption are key preventative measures. Regular health screenings are important to detect any underlying conditions that might increase the risk of SCA, especially for individuals with a family history of heart disease.

Being aware of and promptly responding to heart problem symptoms, such as chest pain or irregular heartbeat, is critical. Stress management techniques can also play a role in maintaining heart health. For those on heart-related medications, adherence to the prescribed regimen is vital. If you have a heart condition then keep a close eye on your cholesterol levels and discuss options with your doctor.