An AED can improve the chance of survival for a sudden cardiac arrest victim by as much as 90%. Without a defibrillator, the odds of survival drop 10% for every minute that passes.
Finding a defibrillator and applying it within this 10 minute ‘window of opportunity’ can make all the difference.
Automated External Defibrillators are generally placed in accordance with this advice:
When trying to locate a defibrillator, consider the time of day and whether access will be restricted by hours of operation. There’s no time to waste for the person you send to find a defib while you do CPR.
For example, there would be no access to the defibrillator in the library foyer if the library is closed for the day. Operating hours restrict access in many locations.
There are several registers that gather information on the location of AEDs. The largest of these is GoodSAM, which is accessed via a handy phone app called GoodSAM Defibrillocator. The app helps locate the nearest AED based on your location.
A few councils devote webpages to listing AED locations within their areas. This web page acts as a central hub from which to find council websites.
A defibrillator aims to re-establish normal heart rhythm by delivering an electrical shock to the heart muscle. This is intended to treat ventricular fibrillation.
The current is passed to the heart muscle through pair of electrodes and gel, which facilitates electrically conductivity and prevents electrical burns.
The shock depolarises the cardiac muscle in an attempt to "re-align" it with the body’s natural pacemaker.
To pump oxygenated blood the heart relies on electrical impulses to prompt its muscles to contract and release.
The shock lasts approximately eight milliseconds and is rated anywhere between 200 volts and 1000 volts, at 360 joules, and 45 amps. Modern defibrillators use adhesive pads, whereas traditional defibrillators had metal paddle electrodes with insulated handles.
Ventricular fibrillation (VF) is a changed heart rhythm stemming from the bottom chambers of the heart. This abnormal heart rhythm is very short and frequent.
A heart attack is a likely cause.
Beating at over 300 beats per minute typically, VF pulses are too short to push blood from the ventricles. Without immediate intervention, the resulting low blood pressure and loss of circulation in the body can cause loss of consciousness, or death.
Emergency treatment includes immediate CPR and defibrillation with an AED.
Ventricular fibrillation is not the only reason a heart would need a defibrillator.
Ventricular tachycardia is another common form of cardiac distress a defibrillator could correct. The chaotic heartbeats, typically at 100 or more beats a minute, don’t allow the heart chambers to properly fill with blood, reducing effective circulation.
When the electrodes of an automated external defibrillator are positioned on the patient’s chests, it begins diagnosing the heart rhythms. No shock will be administered unless treatable ventricular fibrillation is detected.
You don’t need training, which makes an AED a game-changer in terms of responding to out-of-hospital cardiac arrests.
A defibrillator will not restart a heart that has flatlined — in asystole (ay-sis-stuh-lee). The defibrillator will work only when it detects a treatable electrical pulse.
Survival rates of Sudden Cardiac Arrest victims are highest when defibrillation is administered within the first few minutes. Survival rates will improve through greater defibrillator availability and quick access to them.
DRSABCD is the strategy used in medical emergencies for basic life support.