Cardiac arrest (or sudden cardiac death) is caused by a chaotic irregular fibrillation of the heart that is not sustainable with life. There are many causes of this. The most common in the US is caused by a ongoing heart attack or as a result of the scar left from an old heart attack. Other causes of these fatal heart rhythms included genetic disorders, inherited or acquired weakening of the heart muscles, or toxin induced (cocaine, amphetamines ...).
As the AHA states in its letter to the Jackson family, more than 300,000 people suffer sudden cardiac arrest outside the hospital. More than 90% of these individuals do not survive. Treatment of these patients must included immediate CPR and then defibrillation (electrical shock - like seen on TV). It has been shown that the most important part of the CPR process is the chest compressions. This circulates the blood to the brain and also oxygenates the blood by expanding compressing and decompressing the lungs. We have been trying to promote this "hands on" approach in my community. Forget about the mouth to mouth component and just start chest compressions and call 911 immediately. If patients are treated like this within 4 minutes, must will have an excellent outcome. If patients are treated in 4-8 minutes, the results are iffy. If patients are not treated for over 10 minutes, the results are dismal.
As I wrote about in my previous blog, Absolutely Amazing, a defibrillator makes all the difference. Whether it is implanted in a patient or brought to the seen by the EMS, life will not be restored if the patient is not shocked out of fibrillation.
Please make yourself aware of the signs and symptoms of a heart attack. Call 911 immediately if you or anyone near you if suffering any of these symptoms.
If you see a person collapse assess them. If there is no pulse or they are not breathing - call 911 and start CPR. In most urban and suburban communities, emergency medical services should be able to reach you in less than 5 minutes. Most firetrucks and policecars now carry defibrillators and the service men have been trained in their use.
If you have had a heart attack, you MUST know your ejection fraction. This can be determined easy with a cardiac ultrasound (echocardiogram). Normal is 55-60%. Patients with ejection fractions less than 35% are considered for an impantable defibrillator due to the 1-2% yearly risk of sudden cardiac death.
If you have been told you have a weakened heart (not caused by a heart attack) you to need to know your ejection fraction. If it is less than 35%, you too may benefit from an implantable defibrillator.