An automated external defibrillator (AED) delivers an electric shock to the heart to stop ventricular fibrillation and allow a normal rhythm to resume following sudden cardiac arrest; AEDs guide lay rescuers through the process of applying pads to the patient's chest, analyzing their heart rhythm, and delivering a shock if needed to restore a normal rhythm; It is critical to place AED pads correctly on the patient's chest, follow all prompts, and continue CPR between shocks to improve chances of survival from sudden cardiac arrest.

1. Automated external defibrillator
Aminu M Hussain

3. Objectives
• Define AED
• Understand the principles
• Know how to operate
• Know the importance of AED

4. Introduction
• An automated external defibrillator (AED) is a
lightweight, portable device that delivers an
electric shock through the chest to the heart.
• The shock can potentially stop an irregular heart
beat (arrhythmia) and allow a normal rhythm to
resume following sudden cardiac arrest (SCA).
• SCA occurs when the heart malfunctions and
stops beating unexpectedly. If not treated within
minutes, it quickly leads to death.

5. • Most SCAs result from ventricular fibrillation
(VF). VF is a rapid and unsynchronized heart
rhythm that originates in the heart’s lower
chambers (the ventricles).
• The heart must be “defibrillated” quickly,
because a victim’s chance of surviving drops
by seven to 10 percent for every minute a
normal heartbeat isn’t restored.

6. Cardiac arrest
If you find a person who is:
• Unconscious
• Unresponsive
• Not breathing, or
• Not breathing normally
They are in “CARDIAC ARREST”

7. AED
AED – this stands for:
A = Automated
E = External
D = Defibrillator

8. What is a ‘defibrillator’?
A defibrillator (AED) is a device that gives a
high energy electric shock to the heart of
someone who has collapsed and is in
cardiac arrest.
This high energy shock is called
defibrillation, and it’s essentially part in trying
to save the life of someone who’s in cardiac
arrest.

9. What is a defibrillator?
• When the heart goes into a sudden cardiac
arrest, it enters into some quivering mode, which
is termed ‘ventricular fibrillation.
• A defibrillator is a device used to jolt it out of that
mode. It is a machine that sends a high-energy
electric shock to the heart to restore it to its
reasonable working condition.
• Defibrillators are usually of two types.
• Automated external defibrillators (AEDs)
• Manual external defibrillators

11. There are a number of makes of defibrillator.
They all do the same job, and each type
talks you through what you need to do.
There is no need to worry, you won't be able
to shock someone who doesn’t need it as
the AED will only deliver a shock if it’s
required!

12. How exactly does an AED work?
• Fibrillation is a significant symptom of a heart attack. It is a
state of the erratic beating of the heart. AED aims to stop
that irregular beating of the heart. But how does this AED
work?
• This device does do so by generating a relatively high
electrical current (up to 360 joules for some models of
AEDs) and then passing it through to the heart. In this way,
the heartbeat comes back to normal immediately.
• Once the heart starts beating (shown in the ECG machine
as flat lines), the person is dead. Even though the AED has
excellent capacities, saying that it restarts the heart is more
like an exaggeration of what it can do.

13. Why are AEDs important?
• AEDs make it possible for more people to
respond to a medical emergency where
defibrillation is required.
• Because AEDs are portable, they can be used by
nonmedical people (lay-rescuers). They can be
made part of emergency response programs that
also include rapid use of 9-1-1 and prompt
delivery of cardio pulmonary resuscitation (CPR).
All three of these activities are vital to improving
survival from SCA.

14. How does an AED work?
• A built-in computer checks a victim’s heart rhythm
through adhesive electrodes. The computer calculates
whether defibrillation is needed. If it is, a recorded
voice prompts the rescuer to press the shock button on
the AED.
• This shock momentarily stuns the heart and stops all
activity. It gives the heart the chance to resume beating
effectively. Audible prompts guide the user through the
process. AEDs advise a shock only for ventricular
fibrillation or another life-threatening condition called
pulseless ventricular tachycardia.

15. Using an AED
• Turn on the AED.
• Attach the pads to the person’s bare, dry
chest, as shown on the pads.
• Make sure no one is touching the person and
say “Clear!”
• Allow the AED to analyze the rhythm.
• Follow the prompts.
– The AED will either direct you to push the Shock
button or to begin CPR.

16. • Give 5 sets of CPR unless the person moves,
begins to breathe, or wakes up.
• Repeat Steps until the person moves, begins
to breathe, or wakes up.

17. Where to place the pads?
• Where you place the pads is quite essential as its
correct placement would ensure that the electric
current released can circulate all through the
patient’s heart.
• There are two correct places to place the pad.
• Place one AED pad under the collarbone on the
upper-right chest. Place the second AED pad near
the left armpit on the patient’s lower ribcage.
• In front and behind the heart (typically for
children aged under 8)

19. Within hospital
• 1 Assess patient for unresponsiveness, not breathing and
pulselessness. These are indicators of cardiopulmonary
arrest.
• 2 Activate code team in accordance with hospital policy and
procedure. First available person brings resuscitation cart
and AED.
• 3 Start chest compressions and continue until AED is
attached to patient and verbal prompt of device advises
you, “Do not touch the patient.” To minimize interruption
time of chest compressions, continue CPR while AED is
being applied and turned on.
• 4 Place AED next to patient near chest or head. Ensures
easy access to device.

20. • 5 Turn on power. Turning on the power will begin the verbal
prompts to guide you through the next steps.
• 6 Attach the device. Place the first AED pad on the upper right
sternal border directly below the clavicle. Place the second AED pad
lateral to the left nipple with the top of the pad a few inches below
the axilla . Ensure that cables are connected to the AED.
• Alternative pad placement of AED pads is not recommended.
• AEDs analyze most heart rhythms using lead II. If the AED pads are
placed as directed, patient’s heart rhythm will be analyzed in lead II.
• Patients with large amounts of chest hair may require shaving to
obtain adequate pad contact.

21. • 7 Do NOT touch patient when AED prompts you. Direct rescuers and bystanders to
avoid touching patient by announcing “Clear!” Allow the AED to analyze the
rhythm. Some devices require that an analysis button be pressed. The AED takes
approximately 5 to 15 seconds to analyze the rhythm.
• 8 Before pressing the shock button, announce loudly to clear the victim and
perform a visual check to ensure that no one is in contact with him or her. Clearing
patient ensures safety for those involved in rescue efforts.
• 9 Immediately begin chest compression after the shock and continue for 2
minutes. Do NOT remove the pads. Continues cardiac perfusion.
• 10 Deliver two breaths using mouth-to-mouth with barrier device or mouth-to-
mask device or bag-mask device. Watch for chest rise and fall. Deliver 10-to-12
breaths/min.
• In a hospital setting where protected methods of artificial ventilation are
available, mouth-to-mouth without a barrier device is not recommended because
of risk for microbial contamination.
• 11 After 2 minutes of CPR, the AED will prompt you not to touch patient and will
resume analysis of patient’s rhythm. This cycle will continue until patient regains a
pulse or physician determines death.

22. • Recording and Reporting
• Immediately report arrest via the hospital-wide
communication system, indicating exact location of victim.
• Cardiopulmonary arrest requires precise documentation.
Most hospitals use a form designed specifically for in-
hospital arrests.
• Record in nurses’ notes and EHR or on designated CPR
work sheet: onset of arrest, time and number of AED
shocks , time and energy level of manual defibrillations,
medications given, procedures performed, cardiac rhythm,
use of CPR, and patient’s response.

23. Questions
• Is there difference in approach based on age
of patient
• How many types of defibrillator
• what is the use of a defibrillator
• Who can operate a defibrillator
• What principles need to be considered when
using AED