The document outlines the principles and procedures related to cardiac defibrillation, including the anatomy and physiology of the heart, types of defibrillation, and emergency procedures for managing cardiac arrest. Key differences between defibrillation and cardioversion are detailed, highlighting their applications, energy levels, and risks involved. It also covers pre- and post-procedural care, complications, and documentation requirements to ensure comprehensive patient management and legal adherence.

1. Cardiac Defibrillation
By-Hrishikesh D Gore
PIMS(DU),CON

3. outline
 Anatomy and Physiology
 Cardiac arrest
 Definition Cardiac Defibrillation
 History
 Definition Cardioversion
 Difference between defibrillation and Cardioversion
 Difference between monophasic and biphasic defibrillation
 Equipments for cardiac defibrillation
 Pre procedural consideration
 Care of patient before cardiac defibrillation
 Cardiac Defibrillation procedure
 Post procedural care of patient
 Complications
 Documentation and legal aspects
 Take home points

4. Anatomy and Physiology of Heart
 The heart is a muscular organ which pumps blood through the blood
vessels of the circulatory system
 An adult heart has a mass of 250–350 grams
 The heart has four chambers that right atrium ,left atrium, right
ventricle, and left ventricle
The valves of the heart are
 The tricuspid valve-between the right atrium and the right ventricle
 The pulmonary valve- lies between the right ventricle and
the pulmonary artery
 The mitral valve- lies between the Left atrium(LA) and the left
ventricle(LV)
 The aortic valve- lies between the Left ventricle and the Aorta.

5. Layers of the Heart
 The heart wall is comprised of three layers, the
Epicardium, myocardium and Endocardium
 Epicardium – Outer layer
 Myocardium – Middle Layer
 Endocardium – Inner Layer

6. The Conduction System
 Electrical impulses Generated at S A Node
S A Node
Internodal Pathway
A V Node
Bundle of His
Right and Left Bundle Branch
Purkinje Fibers
Contraction of Heart

7. Cardiac Arrest
 Cardiac arrest is a sudden and unexpected loss of perfusing pulsatile
blood flow attributable to cessation of cardiac mechanical activity. It
occurs as a result of a dysfunction of cardiovascular, metabolic,
infectious, neurologic, inflammatory, and traumatic diseases.
 These diseases can be generally classified into :
 5 H's - Hypovolemia, Hypoxemia, Hydrogen ion (acidosis), Hypo- or
Hyperkalemia, Hyperlipidemia
 5 T's - Tension pneumothorax,Tamponade, Toxins, and Thrombosis–
both pulmonary and cardiac).
 The endpoint of these disorders is commonly pulseless ventricular
tachycardia (VT) or ventricular fibrillation (VF), pulseless electrical
activity, or asystole.

8. Definition
 Defibrillator is a device that deliver a therapeutic dose
of electrical energy (electric shock) to the affected
heart (fibrillated heart or other shockable rhythm) to
force the heart to produce normal cardiac rhythm.

9. History
First demonstrated on dogs in 1899 by Jean-Louis Prévost &
Frederic Batelli, two physiologists from University of Geneva,
Switzerland.
The first use on a human was in 1947 by Claude Beck, professor of
surgery at Case Western Reserve University.
Transthoracic defibrillation was first used in humans using
alternating current (AC)
Bernard Lown and his co-workers introduced direct current (DC)
defibrillators into clinical practice.

10. Cardioversion
 It is any process that aims to convert an arrhythmia back to
sinus rhythm by therapeutic dose of electrical energy

11. Difference between Defibrillation and
Cardioversion

12. Defibrillation Cardioversion
Emergency life saving procedure Elective planned procedure
Un-synchronized shock Synchronized shock
High energy shock Low energy shock
More damage to myocardium Less damage to myocardium
Used in VT / VF Used in most of the arrhythmias
except VT /VF
Can be given at any time of
Cardiac cycle
Can be given in Ventricular
Contraction

13. Difference between Monophasic and
Biphasic Defibrillation

14. Monophasic Defibrillation Biphasic Defibrillation
current travels only in one direction deliver current in two directions
It requires more electrical energy It requires less electrical energy
It causes more trauma It causes less trauma
It has more chances of burn It has fewer chances of burn
It causes more myocardial damage It causes less myocardial damage
First shock success rate is 60% First shock success rate is 90%

15. Equipments for Cardiac Defibrillation
 Defibrillator

16.  Conductive jelly or pads

17.  Cardiac monitor

18.  Blood pressure monitor

19.  Pulse Oxymeter

20.  Emergency cart and medications

21.  Emergency pacing equipment

22. Pre procedure considerations
1. If the patient is alert or pulse is present then defibrillation
should not be performed, it can lead to cardiac arrest or lethal
heart rhythm disturbances.
2. Part preparation should be done before performing procedure.
3. The paddles should not be placed on internal pacemaker.

23. Care of patient before cardiac
defibrillation
 Check Vital signs

24.  Check for consciousness

25. 3.Open airway

26. 4.Continue with CPR till defibrillator arrives

27. 5.Skin preparation of patient (If possible)

28. 6.Continue ECG monitoring

29. 7.Remove NTG patch

30. 8.Secure IV line for Resuscitation medication as per ACLS
protocol

31. 9.Intubation and oxygen supplementation

32. Guidelines of Using Cardiac
Defibrillator (S.O.P)
1.Check And confirm charging of defibrillator
2.Connect to the Direct current source
3.Check for working condition and Calibration of defibrillator
4.Check for Backup power
5.Check for the printer of defibrillator.

33. Cardiac Defibrillation Procedure

34. Procedure Rationale
1.Identify ventricular fibrillation (VF) on the
monitor. Check leads, confirm pulselessness.
1.No unnessary shock.
2.Call an arrest.(Code Blue) 2.To obtain appropriate and adequate
personnel to manage the airway, do chest
compressions, and prepare and administer
medications.
3.May "thump" the precardium. 3.May generate enough stiumulation to
defibrillate the patient if done early in VF.
4.Initiate CPR until defibrillator available. 4.Maintain oxygenation/circulation to brain
and heart. Defibrillate as soon as possible.
5.Prepare the machine for defibrillation:
_ Plug cart in.
_ Set charge at 300 joules.
_ If time allows, apply leads from cart
monitor.
_ Set to "defibrillate"
5.Initial voltage of 200-300 joules (watts) is
recommended by the AHA.
Establishment of fibrillation shouldn't delay
defibrillation.
The defibrillator will not fire if the machine
is on synch (for cardioversion).

35. Procedure Rationale
6.Prepare patient for defibrillation:
_ side rail down
_ bed and patient flat
_ apply gel pads in correct position
one above, one below heart
at least 2 cm. away from electrodes.
6.Provide better access to patient.
Prevents burns from defibrillator. Reduces
resistance of skin to the electrical current.
Current through myocardium will
depolarize as much myocardium as
possible.
- prevents arcing between paddles and
electrodes and burning of patient.
7. Quick look at monitor while shouting all
clear.
7.In the event of rhythm change.
8.Firmly press paddles onto gel pads and
discharge by simultaneously
depressingbuttons.
Be sure to depress buttons firmly and hold
for 2 seconds.
Ensure no contact with metal on bed, all
personal away from bed contact.
8.Two pounds pressure required to
ensure contact.
To safely deliver charge.
Premature release of buttons may
result in failure to discharge energy.

36. Procedure Rationale
9.Reassess rhythm and pulse. 9.Assess response.
10.Recharge paddles. 10.Ready for repeat.
11.If VF persists, increase charge to
maximum 360 joules and repeat.
11.The amount of energy needed to
convert VF rapidly increases with time.
Chest wall resistance decreases with
rapidly successive shocks. May be easier
to defibrillate.

37. Procedure Rationale
12.Administer lidocaine bolus, 1 mg/kg
and start an infusion at 2 mg/min as per
"L" Lidocaine, Administration
Procedure.
12.To minimize recurrance. Defibrillate
first to avoid delay in converting
rhythm. Some studies have indicated
that lidocaine may reduce
responsiveness to defibrillation.
13.If unsuccessful:
Continue CPR
13.Troubleshoot for possible physical
causes, eg., acidosis, hypoxia. Ensure
adequate paddle pressure, machine off
synchronization.
14.Obtain medical support STAT, may
need to call second on-call
Safety to health care workers.
14.For medical intervention.
15.If successful:
_ maintain airway
_ ensure breathing
_ monitor circulation
15.Hypoxia or acidosis may be present.
Ready for repeat.

38. Procedure Rationale
16.Assess and treat for side effects:
burns, arrhythmias, anxiety.
16.The amount of energy needed to
convert VF rapidly increases with time.
Chest wall resistance decreases with
rapidly successive shocks. May be easier
to defibrillate.
17.Reassure patient, notify family. 17.To minimize recurrance. Defibrillate
first to avoid delay in converting
rhythm. Some studies have indicated
that lidocaine may reduce
responsiveness to defibrillation.
18.Document rhythm strips, graphics,
shock and resuscitation record.
18.Troubleshoot for possible physical
causes, eg., acidosis, hypoxia. Ensure
adequate paddle pressure, machine off
synchronization.

39. Post procedural care of patient
 Assess the ECG and pulse after defibrillation.
 If the first counter shock is unsuccessful, immediate
defibrillation must be performed again at a higher energy level.
 Monophasic defibrillation may be applied up to three times.
 If the defibrillation have not been successful,CPR should be
continue.
 The clients vital signs and neurologic status must also be
continuously assess.

40. Complication
 Soft tissue injury

41.  Myocardial and epicardial injury

42.  cardiac dysrhythmias
•Electrical injuries to health care providers
•Fires

43. DOCUMENTATION FOR THE
MEDICAL RECORD
 Code Sheet
 Progress Notes
 ECG
 Treatment chart

44. Legal Aspects

45.  Consent for Cardioversion (in case of Cardioversion)
 Records and reports
 Do not Resuscitate
 Training

46. Take Home Points
 Definition of Cardiac Defibrillation-Defibrillator is a device that
deliver a therapeutic dose of electrical energy (electric shock) to the
affected heart (fibrillated heart or other shockable rhythm) to force the
heart to produce normal cardiac rhythm
 Definition of Cardioversion- It is any process that aims to
convert an arrhythmia back to sinus rhythm by therapeutic
dose of electrical energy
 Paddle size
Adult -10-13cm
Pediatric- 4.5-8cm
 Pressure of Paddles – 25Pounds

47. Energy Selection-
Monophasic – 360J
Biphasic – 150J – 360J
 As per AHA recommended initial dose of defibrillation is 2J/kg and
up to 4J/kg
 Medical Emergency code color – Blue(Code)
 Chanting of “I Clear” “You Clear” “All Clear”
 If Patient is not reverted with Cardiac defibrillator continue with
CPR
 Look for Complications like Burn injuries

48. Defibrillation Cardioversion
Emergency life saving procedure Elective planned procedure
Un-synchronized shock Synchronized shock
High energy shock Low energy shock
More damage to myocardium Less damage to myocardium
Used in VT / VF Used in most of the arrhythmias
except VT /VF
Can be given at any time of
Cardiac cycle
Can be given in Ventricular
Contraction
Difference between Cardiac Defibrillation and Cardioversion