<P> AEDs, like all defibrillators, are not designed to shock asystole (' flat line' patterns) as this will not have a positive clinical outcome . The asystolic patient only has a chance of survival if, through a combination of CPR and cardiac stimulant drugs, one of the shockable rhythms can be established, which makes it imperative for CPR to be carried out prior to the arrival of a defibrillator . </P> <P> Uncorrected, these cardiac conditions (ventricular tachycardia, ventricular fibrillation, asystole) rapidly lead to irreversible brain damage and death, once cardiac arrest takes place . After approximately three to five minutes in cardiac arrest, irreversible brain / tissue damage may begin to occur . For every minute that a person in cardiac arrest goes without being successfully treated (by defibrillation), the chance of survival decreases by 7 percent per minute in the first 3 minutes, and decreases by 10 percent per minute as time advances beyond ~ 3 minutes . </P> <P> AEDs are designed to be used by laypersons who ideally should have received AED training . However, sixth - grade students have been reported to begin defibrillation within 90 seconds, as opposed to a trained operator beginning within 67 seconds . This is in contrast to more sophisticated manual and semi-automatic defibrillators used by health professionals, which can act as a pacemaker if the heart rate is too slow (bradycardia) and perform other functions which require a skilled operator able to read electrocardiograms . </P> <P> Bras with a metal underwire and piercings on the torso must be removed before using the AED on someone to avoid interference . American television show Mythbusters found evidence that use of a defibrillator on a woman wearing an underwire bra can lead to arcing or fire but only in unusual and unlikely circumstances . </P>

Who are aeds designed to be used by
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