This is a brief description of how defibrillator work. It is especially talking about AED (automatic external defibrillator). It explains how it works and mechanism behind its easy but effective result.

1. DEFIBRILLATOR

2. ADVANCEDLIFE SUPPORT SYSTEM(ALS)
These tools are used
in the healthcare
setting such as in
hospitals and
ambulances and allow
staff to monitor the
patient’s heart rhythm
and intervene
manually if a shock is
required.

3. What is DEFIBRILLATOR?
It is an electrical device that delivers a
therapeutic dose of electrical energy to
the heart to stop defibrillation.
Defibrillation is a common treatment for
life-threatening cardiac
dysrhythmias and ventricular fibrillation.

4. How electric shock helps the
heart? The heart requires the orderly sequential contraction of the
atria and ventricles in order to pump blood through the rest of
the body.
 Orderly contraction is regulated by electrical activity starting
in the right atrium, passing through the atrioventricular node,
and into the ventricles. This electrical activity is spontaneous -
without outside stimulus, cells in the heart will spontaneous
depolarize and contract at a slow basal rate.
 During cardiac arrest, the heart does not stop - rather there is
disordered electrical activity that leads to ineffective
contraction and inadequate blood flow.

6. Implantable cardioverter defibrillators (ICDs)
 These units are placed
directly into the chest of
patients who are at high
risk of sudden death, such
as those with a medical
conditions known to put
them at risk or patients
who have already
experienced ventricular
fibrillation or ventricular
tachycardia.

7. Wearable Defibrillator
 A wearable defibrillator straps on to
the outside of the patient to
provide continuous monitoring
through non-adhesive electrodes.
 It provides a valuable treatment
option for patients at risk for
sudden cardiac arrest or sudden
cardiac death, especially for those
who cannot get an implantable
device due to cost or health issues.

8. Automatic External Defibrillators (AED)
An AED is a small
portable device that
contains a computer to
assess the heart
rhythm through the
use of adhesive
electrodes. The
computer then judges
if the patient requires
defibrillation can

9. AEDIn 1947 Claude Beck successfully used
an electrical shock to restore a
normal rhythm to the heart of a 14
year old boy.
 It is a safe and easy to use device
that delivers a therapeutic electric
shock to the heart as treatment for a
victim in Sudden Cardiac Arrest (SCA).

10. Components of AED
Battery
Electrodes
Control Computer

11. Why Do We Use AED?
Automatic refers to the ability to autonomously
analyze the patient's condition.
An AED is the most convenient and user friendly
as well as portable of all the other defibrillators.
It is provided with self-adhesive electrodes
instead of hand held paddles.
It is small and has less components than the
other defibrillator systems.
They don’t require much maintenance as their
battery lasts for 10 years.

12. Semi-automatic AEDs Fully automatic AED
Definition Indicates the need for defibrillation
but
requires an operator to deliver the
shock by
pushing a button.
Capable of administering a shock
without the
need for outside interventions.
Advantages • Widely used
• Allows healthcare professionals to
override
the device and deliver a shock
manually,
independently of prompts.
• Safer, no risk of inappropriate
shocks to
the rescuer
• Easier to use and more appropriate
for layrescuers
• Better compliance with
resuscitation protocols
Disadvantages • More complex to use for the
untrained
responders
• More difficult to synchronize with
CPR.
• Longer times until shock delivery
• Risk of electrocution for the
rescuer if
inappropriately used
• No possibility to override the
device
• Not recommended by current
guidelines except

13. How Does An AED Work?
 Energy storage capacitor is charged at relatively
slow rate from AC line.
 Energy stored in capacitor is then delivered at a
relatively rapid rate to chest of the patient.
 Simple arrangement involve the discharge of
capacitor energy through the patient’s own
resistance.

15. CONCLUSION
 Sudden cardiac arrest, frequently due to VF
or pulseless VT, is traditionally associated
with poor survival rates. Saving the lives of
these patients depends on early cardiac
defibrillation which, with manual
defibrillators, is limited only to qualified
rescuers who can interpret ECGs. AEDs
solve this problem since they are able to
analyze rhythm and inform the rescuers
whether a shock is needed.