What is Sudden Cardiac Arrest?
Sudden cardiac arrest
(SCA) simply means that the heart unexpectedly and abruptly quits
beating. This is usually caused by an abnormal heart rhythm called
ventricular fibrillation (VF). Approximately 235,000 Americans
suffer SCA each year without warning. It can leave the victim dead
within a matter of minutes.
Is Sudden Cardiac Arrest the same as a heart
attack?
No. A heart attack is a condition in which the blood
supply to the heart muscle is suddenly blocked, resulting in the
death of the heart muscle. Heart attack victims usually (but not
always) experience chest pain and usually remain conscious. Heart
attacks are serious and sometimes will lead to sudden cardiac
arrest. However, sudden cardiac arrest may occur independently from
a heart attack and without warning signs. SCA results in death if
not treated immediately.
Who is at risk for Sudden Cardiac Arrest?
SCA is
difficult to predict and most victims have no prior symptoms. Anyone
who has suffered SCA, a heart attack, or knows they have an
arrhythmia may be at greater risk for this malady. While the average
age of sudden cardiac arrest victims is around 65, sudden cardiac
arrest can strike anyone, anywhere, and at anytime.
What is Ventricular Fibrillation?
Ventricular
fibrillation (VF) is an abnormal heart rhythm often seen in sudden
cardiac arrest. This rhythm is caused by an abnormal and very fast
electrical activity in the heart. VF is chaotic and unorganized; the
heart just quivers and cannot effectively pump blood. VF will be
short lived and will deteriorate to asystole (a flat line) if not
treated promptly. For each minute that VF persists, the likelihood
of successful resuscitation decreases by approximately 10
percent.
What is Defibrillation?
The only effective treatment
for VF is an electrical shock called defibrillation. Defibrillation
is an electrical current applied to the chest, and to be successful,
should be administered within 3 to 5 minutes after collapse. The
electrical current passes through the heart with the goal of
stopping the VF and giving an opportunity for the heart's normal
electrical system to take control and pump blood again. After 10
minutes without defibrillation, very few resuscitation attempts are
successful. An AED can defibrillate the heart.
What does AED stand for?
AED stands for automated
external defibrillator.
What is an AED?
An AED is a device used to administer
an electric shock through the chest wall to the heart. Built-in
computers assess the patient's heart rhythm, judge whether
defibrillation is needed, and then administer the shock. Audible
and/or visual prompts guide the user through the process.
What if I mistakenly apply the AED to someone who fainted but
still has a pulse which I couldn't feel?
The AED makes shock
delivery decisions based upon the patient's heart rhythm, and will
not allow a shock to be delivered if not needed. Simply put, the
machine will not let you shock a non-shockable rhythm.
How do I recognize the need for
defibrillation?
Remember this rule: only put the unit on
someone you would do CPR on... someone who is unresponsive, not
breathing, and has no pulse.
What if I forget the steps for using the AED?
The steps
for shocking a patient in cardiac arrest are simple and
straightforward. Just follow the visual and audio prompts provided
by the AED. The most difficult part is actually recognizing the need
for defibrillation.
What if I can't hear the voice prompts of the AED?
Look
for the visual text prompts on the AED screen.
Should I do CPR first or apply the AED?
Do CPR only
until the AED arrives. Apply the electrodes to the patient's bare
chest and follow the voice prompts and messages of the AED. It will
tell you when to resume CPR. CPR is a holding action until the heart
is defibrillated.
If defibrillation is so important, why should I do
CPR?
CPR provides some circulation of oxygen-rich blood to
the victim's heart and brain. This circulation delays both brain
death and the death of the heart muscle. CPR buys some time until
the AED can arrive, and it also makes the heart more likely to
respond to defibrillation.
Can I be sued using the defibrillator?
To date, there
has never been a case where someone was held liable for using an
AED. However, there have been lawsuits for not having an AED
regarding the "standard of care." Most states have passed "Good
Samaritan" legislation protecting the lay rescuer from lawsuits.
Can I accidentally shock myself or another
rescuer?
AEDs are extremely safe when used properly. The
electric shock is programmed to go from one pad to another through
the victim's chest. Basic precautions, such as verbally warning
others to stand clear and visually checking the area before and
during the shock, can ensure the safety of rescuers.
Do I need to remove the defibrillator pads before doing chest
compressions?
No. The pads remain on throughout the
resuscitation and until the patient is transferred to advanced care
providers such as paramedics. If the pads are in their correct
locations on the patient's chest, they will not interfere with
proper hand placement or compressions.
Should I use the AED if the patient has a pacemaker or is
pregnant?
Absolutely. Never withhold AED use from a person in
cardiac arrest. If the person in question meets all the criteria of
cardiac arrest (unresponsive, not breathing, no pulse) they are
essentially "dead."
Can I defibrillate on a wet surface?
Yes, as long as
the usual safety precautions are observed. Be sure the victim's
chest is wiped dry. Keep the defibrillator electrodes away from a
damp or conductive surface. Clear the victim and defibrillate.
How much of the patient's clothing needs to be removed to
carry out defibrillation?
The chest should be exposed to
allow placement of the disposable defibrillation electrodes. A
woman's bra should be removed. Clothes may need to be cut off to
facilitate early defibrillation.
Do physicians and nurses know how to defibrillate?
Not
all medical personnel know how to defibrillate, or they may not be
familiar with the type of defibrillator you are using. Once you have
been trained, continue to use it. Medical personnel may be needed to
administer drugs, and give other advanced medical care.
After I have successfully defibrillated the victim and have
return of a pulse, do I keep the AED on the patient?
Yes,
even after the patient has been successfully defibrillated, they are
still at risk of developing ventricular fibrillation again. The AED
will continually monitor the victim for the return of VF. If VF is
suspected, the device will prompt you. The AED should be left on
until emergency personnel assume responsibility for the patient. The
defibrillation pads (electrodes) are disposable.
What if the patient regains a pulse but is not breathing or is
breathing slowly?
Give rescue breaths at a rate of 1 every 5
seconds, or 12 per minute.
I shocked a woman in cardiac arrest 3 times within minutes
after she collapsed. I heard later that she did not survive. Did I
do something wrong?
Unfortunately, because of other
underlying medical or heart problems, not all victims of cardiac
arrest who are in ventricular fibrillation (VF) will survive, even
if defibrillation is done promptly and correctly.
What if I don't perform all the steps of CPR and
defibrillation perfectly?
A cardiac arrest is a high stress
situation. Even the most experienced health care providers do not
always do everything perfectly. In a cardiac arrest, performing CPR,
even imperfectly, and using a defibrillator can only help the
patient.
Is it okay to place the electrodes directly on a hairy
chest?
Electrodes must come in direct contact with the skin.
If the chest hair is so excessive as to prevent good adhesion of the
electrode, the hair must be removed quickly.
What if the victim is a child?
Follow your protocols
regarding the lower age or size limits for children. The American
Heart Association recommends no one under 8 years old receive
defibrillation with an automated external defibrillator.
Can anyone buy an automated external
defibrillator?
AEDs are devices manufactured and sold under
guidelines approved by the FDA. Current FDA rules require a
physician's prescription to buy an AED.
How much does an AED cost?
The price of an AED varies
by make and model. Most AEDs cost around $2,500.