Sudden Cardiac Arrest

Early defibrillation via the use of automated external defibrillators (AEDs) is replacing cardiopulmonary resuscitation in importance during the process of reversing “sudden cardiac arrest” (SCA).

Today’s emergency sudden cardiac arrest procedures start by calling 911, then immediately use an AED to defibrillate the victim to restore a normal heartbeat, then perform cardiopulmonary resuscitation (CPR) until emergency medical services (EMS) arrive on scene.

For many years, CPR was the only therapy used when someone's heart went into “fibrillation”… abnormal beating or quivering or worse even stopped.

Now, many experts suggest using automated external defibrillators, first; then provide CPR.

Operating an automatic model AED is much easier to perform than CPR. AEDs are more powerful tools than CPR chest compressions are for restoring the heart’s normal rhythm.

It takes time, strength or stamina to properly perform CPR and get the best results. CPR is difficult because if compressions are done too slowly or too shallow; the heart may not restart on its own. 

Increasingly CPR is used to maintain the heart beat after defibrillation.

An easy to use “automatic operation” model AED works by opening the lid and following simple voice commands that instruct the operator.  The AED’s software then analyzes the victim and determines whether to deliver a “biphasic” shock to the heart to restore its rhythm.

Today, AED/CPR classes are the teaching standard of nationally accredited organizations (AHA, ARC, ASHI) for employees and students to learn and become certified in the correct methods and techniques of using an automated external defibrillator and giving cardiopulmonary resuscitation (CPR).

Are all AEDs (automated external defibrillators) the same and how do I decide which kind to select?

Two types of defibrillator technologies exist…monophasic versus biphasic…each technology may also feature “escalating energy” (the ability to boost the energy or “joules” delivered) from 200 to 300 to 360 joules to restore normal heart rhythm…and finally; automatic versus semi-automatic operation.

Monophasic AED's (delivers a shock in one direction) may not effectively shock and restore a normal heart rhythm when damaged heart muscle tissue is present.

Biphasic automated external defibrillators (AEDs) were invented to improve effectiveness by delivering a “two-way” (shock in one direction and return the shock in the opposite direction) to the heart muscle in case (very likely) the heart muscle is damaged by a sudden cardiac arrest.

Damage tissue can compromise the effectiveness of a shock.

Biphasic defibrillators also consume less energy than monophasic defibrillators. Biphasic defibrillator technology was invented to replace the vast, aging inventory of monophasic defibrillators.

Automatic operation AEDs are very easy to use. If you are operating this type  you simply press a button to open the lid and a voice directs the operator to first call 911; then to remove the victim’s clothing and expose the victims bare chest; then place the electrodes (or pads) located inside of the lid exactly as shown in the diagram provided; shaving the chest prior to placement when hair is present so the electrodes make firm contact with the skin to assure the electrodes can shock effectively.

The AED’s voice will then tell the operator that the device is “analyzing the heart’s rhythm” and not to touch the victim.

The machine will decide if a shock is necessary and if so will deliver the shock and ask the operator to begin cardo-pulmonary resuscitation.

Semi-automatic operation AEDs function the same way BUT require the operator to make the decision of when the shock is delivered.

Are all AEDs the same and how do I decide which kind to select?

Two types of automated external defibrillator technologies exist…monophasic versus biphasic…each technology may also feature “escalating energy” (the ability to boost the energy or “joules” delivered) from 200 to 300 to 360 joules to restore normal heart rhythm…and finally; automatic versus semi-automatic operation.

Monophasic AED's (delivers a shock in one direction) may not effectively shock and restore a normal heart rhythm when damaged heart muscle tissue is present.

Biphasic AED's were invented to improve effectiveness by delivering a “two-way” (shock in one direction and return the shock in the opposite direction) to the heart muscle in case (very likely) the heart muscle is damaged by a sudden cardiac arrest.

Damage tissue can compromise the effectiveness of a shock.

Biphasic defibrillators also consume less energy than monophasic defibrillators. Biphasic defibrillator technology was invented to replace the vast, aging inventory of monophasic defibrillators.

The devices are also distinguished by how they are operated…automatic versus semi-automatic.

Automatic operation AEDs are very easy to use. If you are operating this type of AED you simply press a button to open the lid and a voice directs the operator to first call 911; then to remove the victim’s clothing and expose the victims bare chest; then place the electrodes (or pads) located inside of the lid exactly as shown in the diagram provided; shaving the chest prior to placement when hair is present so the electrodes make firm contact with the skin to assure the electrodes can shock effectively.

The AED’s voice will then tell the operator that the AED is “analyzing the heart’s rhythm” and not to touch the victim.

The AED will decide if a shock is necessary and if so the AED will deliver the shock and ask the operator to begin cardo-pulmonary resuscitation.

Semi-automatic operation AEDs function the same way BUT require the operator to make the decision of when the shock is delivered.