What is Sudden Cardiac Arrest?
Sudden cardiac arrest is a medical emergency. It is triggered by an electrical malfunction in the heart that causes an irregular heartbeat (arrhythmia). With its pumping action disrupted, the heart cannot pump blood to the brain, lungs and other organs. Seconds later, a person loses consciousness and has no pulse. Death can occur suddenly within minutes if the victim does not receive prompt treatment.
Cardiac arrest is often confused with a heart attack. These terms are used interchangeably but they are not the same. Heart attack on the other hand, occurs when a stenosed coronary artery prevents oxygen-rich blood from supplying a part of the heart muscle. If the blocked artery is not reopened quickly, the section of the heart normally supplied by that artery begins to die. The longer a person goes without treatment, the greater the damage, which may eventually lead to death.
Signs and Symptoms of Heart Attack Include:
- Shortness of breath
- Nausea, heartburn,
- Squeezing, burning or aching sensation in the center of the chest that radiates to the arm, neck, jaw or back.
- Feeling of impending doom.
- Light-headedness or sudden dizziness
- Paleness or cold sweat
Sudden cardiac arrest tends to be more common in adults in their middle age (between 30 and 40 years of age) and affects men twice as often as it does women. This condition is rare in children, affecting only 1 to 2 per 100,000 children each year.
What Causes Sudden Cardiac Arrest?
Most sudden cardiac deaths are caused by abnormal heart rhythms called arrhythmias. The most common dangerous arrhythmia is ventricular fibrillation, which is an irregular, disorganized firing of impulses from the ventricles (the heart’s lower chambers). When this happens, the heart is unable to effectively pump blood and death will occur within minutes, if left untreated.
Patients at risk for a cardiac arrest may have warning signs of chest pain, extreme tiredness, racing heartbeat or syncope.
There are many factors that predispose a person to sudden cardiac arrest and sudden cardiac death. They include
- History of congenital heart defects or blood vessels abnormalities
- A family history of sudden cardiac arrest or sudden cardiac death.
- Coronary artery disease- Risk factors for coronary artery disease include smoking, diabetes, obesity, high cholesterol in the blood, family history of cardiovascular disease.
- Prior history of sudden cardiac arrest.
- Ventricular fibrillation or ventricular tachycardia after a heart attack
- Cardiomyopathies such as hypertrophic cardiomyopathy or dilated cardiomyopathy. This is a pathology of the muscles of the heart, especially muscles of the left ventricle. This leads to a decrease in the heart’s ability to pump blood effectively.
How is Cardiac Arrest Treated?
A sudden cardiac arrest requires immediate cardiopulmonary resuscitation (CPR) for survival. CPR is needed to maintain a flow of oxygenated blood to the body’s vital organs such as the brain.
How to Perform Cardiopulmonary Resuscitation or CPR
- Start by asking if the person is conscious or unconscious. If the person is non-responsive, gently tap his or her shoulder and ask loudly “Are you okay”
- If there is no response, and two people are present at the scene, have one person call the 911 emergency number and the other one begin CPR. If you’re alone and have access to a phone, call 911 emergency number immediately before starting CPR. If you’re alone and rescuing a child, perform a CPR for two minutes before calling for help or using an AED.
- If an AED is immediately available, deliver one shock as instructed by the device, then begin a CPR.
- Begin chest compressions by placing the heel of one hand in the center of the person’s sternum and covering the first hand with the other hand. Aligning your elbows straight, use your upper body weight to push down hard and fast on the person’s chest at a rate of 100 to 120 compressions a minute. For a child, only one hand is required. After every 30 chest compressions, gently tilt the head back and lift the chin up to open the airway. Quickly check for normal breathing, taking no more than 10 seconds. If the person isn’t breathing, give two rescue breaths, making sure the chest rises after a breath. Pinch the nostrils shut and give the first rescue breath lasting one second and watch to see if the chest rises. If it does rise, give the second breath. If the chest doesn’t rise, repeat the head-tilt, chin-lift maneuver and then give the second breath.
- If you haven’t been trained in CPR, continue chest compressions until there are signs of movement or until emergency medical personnel takes over.
- Continue CPR or chest compressions until the person recovers consciousness and is breathing normally or until emergency medical personnel takes over.
For patients who are at a higher risk for cardiac arrest or sudden cardiac death, an implantable cardioverter-defibrillator (ICD) may be implanted as a preventive treatment. An ICD is a tiny device similar in function to the pacemaker of the heart. It is designed to detect and automatically correct an abnormal heart rhythm.
The ICD may be used in patients who have survived sudden cardiac arrest and needs their heart rhythms constantly monitored
How Often do People Survive a Cardiac Arrest?
Cardiac arrest is a leading cause of death and can be an extremely traumatic event for those who survive. Many of those who live through it don’t escape without a certain amount of brain damage; approximately 50% of survivors of cardiac arrest suffer from some amount of cognitive or physical impairment. However, studies are mixed as to the emotional and mental impact of a cardiac arrest event; some studies have found significant amounts of post-traumatic stress disorder, while others have found that victims do not suffer larger amounts of anxiety or emotional disability than people discharged from the hospital for other reasons.
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