Death due to sudden cardiac arrest (SCA) is a big problem. Typically related to heart disease, SCA affects nearly 300,000 Americans each year. As its name suggests, these events occur quickly, and in most cases, without warning. They can occur at any time and in any place.
If one occurs in front of you, you are the only solution. There are only a few minutes between the time SCA occurs and when treatment becomes useless. A bystander has the best and maybe the only chance to help.
How would you deal with a SCA? Simple… you push. Push 911 on your cell phone. Push on the center of the chest. Push hard. Push fast. Push the shock button on the automated external defibrillator. Then, push again on the chest…
Some detail will help.
Your heart is a hollow muscle that squeezes down due to a repeating electrical impulse that goes through its tissue. The contraction forces the blood that fills the heart forward into the body. Moving blood picks up the oxygen you breathe in the lungs and continues on to the rest of the body.
This is how we get oxygen, which is required by the body to live, to individual body cells. The tissue most sensitive to a lack of oxygen is brain tissue. It can only survive a few minutes without oxygen. When there is a significant loss of brain tissue, a person cannot survive.
“Sudden” cardiac arrest occurs when the regular electrical impulses in the heart abruptly go haywire and turn the normal squeezing contraction of the heart into a quivering disorder. Technically this quivering is called ventricular fibrillation, and, when it occurs, the flow of blood from the heart stops. This in turn causes the affected person to suddenly lose consciousness and collapse.
The best way to approach this situation is to think about the underlying problem in two parts, mechanical and electrical. The immediate danger is the lack of oxygen to the brain because the regular blood-moving contractions of the heart have been lost.
The way to manage this part of the problem is to somehow find another way to physically move blood through the body. This is accomplished by performing cardiopulmonary resuscitation (CPR) using a combination of external chest compressions and rescue breaths.
Unfortunately, CPR can only deal with the mechanical part of the problem. CPR is not intended to solve the electrical chaos of ventricular fibrillation. It is also limited in its ability to maintain enough blood flow for an extended period of time. Without addressing the electrical part of the problem, CPR will be unable to effectively treat the problem on its own.2
|What we’ve learned|
Over time we have seen critical components and principles emerge about what we know today when dealing with SCA:
Most importantly, history teaches you how to use simple concepts in your environment (like having those closest to you knowledgeable in CPR and having a ready-to-use AED nearby) to raise the chance of survival, should you, or someone close to you, go into sudden cardiac arrest.
Defibrillation is the use of electricity to “shock” a quivering heart’s electrical activity back into a regular pattern that hopefully can stimulate normal contractions and return spontaneous blood flow. A defibrillator is a device that is designed to deliver defibrillation.
Without CPR, there is generally not enough time for a defibrillator to work. Without a defibrillator, CPR has a very low chance of success.
Historically, surviving SCA has been nearly impossible. The current overall national survival rate for SCA in the U.S. is still low, around 10-15 percent. There has been some improvement for society at large, but remarkable improvements have mostly been seen only in local areas that focus on resuscitation fundamentals. Some local AED programs have survival rates as high as 40-50 percent.
Here are some characteristics of SCA treatment: