cardioversion

1. PRECORDIAL SHOCK
Outline:
Definition
Types of pericardial shock
I. Defibrillation:
 External Defibrillator
1. Manual external defibrillator
 Definition
 Purpose
 Mechanism
 Indications
 Contraindications
 Factors affecting external defibrillation and cardioversion success
 Preparation for external defibrillation
 Procedure of external defibrillation
 After care
 Complications of external defibrillation
2. Automated external defibrillator (AED)
 Internal defibrillation
1. Direct Internal defibrillation
2. Implantable Cardioverter defibrillator (ICD)
II. Cardioversion (Synchronized Cardioversion)
 Definition
 The goal of the electrical cardioversion
 Types of cardioversion
o Chemical cardioversion
o Electrical cardioversion
 Indications
 Contraindications
 Standards
 Cardioversion is usually scheduled ahead of time
 Preparation
 Procedure
 Internal cardioversion
 Post procedure
 Complications
Electrical safety during defibrillation and cardioversion
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2. Objectives:
After review and study of these pages and attendance at an approved nursing skills lab the
critical care student should be able to:
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Defined precordial shock, defibrillation, cardioversion
List types of internal and external defibrillation
Recognize dysrhythmias for which defibrillation might be required
Demonstrate the emergency procedures to be followed as related to defibrillation
Defined the dysrhythmias for which cardioversion might be required.
Demonstrate the procedures to be followed as related to cardioversion.
Differentiate between Cardioversion and Defibrillation
List Electrical safety during defibrillation and cardioversion
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3. PRECORDIAL SHOCK
Definition:
It is delivery of electrical current through heart to depolarize a critical mass of the cardiac muscle
to allow natural pace making tissue to resume control.
Types of pericardial shock:
III.
Defibrillation:
 External defibrillation:
1. Manual external defibrillator.
2. Automated external defibrillator (AED).
 Internal defibrillation:
1. Direct internal defibrillator.
2. Implanted Cardioverter-defibrillator (ICD).
IV.
Cardioversion
I.
Defibrillation
 External Defibrillator
1. Manual external defibrillator
Definition:
“The passage of an electrical current across the myocardium of sufficient magnitude to depolarize a
critical mass of myocardium, and enable restoration of coordinated electrical activity”
Defibrillation is most likely to be effective within the first five minutes, preventing brain injury
and death by returning the heart to a productive rhythm able to produce a pulse.
Defibrillators deliver a brief electric shock to the heart, which enables the hearts natural
pacemaker to regain control and establish a productive heart rhythm.
The current shock deliver through two hand-held paddles or adhesive patches, one electrode is
placed on the right side of the front of the chest just below the clavicle and the other electrode is
placed on the left side of the chest just below the pectoral muscle of breast.
Types of Defibrillators (the machine):
 A monophasic sinusoidal technology / waveform defibrillator (positive sine wave): the
standard of care over the past 40 years provides a shock with current flow in one
direction (from one electrode or paddle to the other).
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4.  A biphasic truncated technology / waveform defibrillators: incorporate two-way current
flow in which electrical current first flows in one direction, then reverses and flows in the
opposite direction.
The more recent use of biphasic cardioversion has shown that less energy is required to convert
an arrhythmia to a normal sinus rhythm.
Purpose of defibrillation:
Defibrillation is performed to restore coordinated cardiac electrical and mechanical pumping action,
restore cardiac output, tissue perfusion, and oxygenation.
Mechanism of defibrillation
It is thought that successful defibrillation occurs when a critical mass of myocardium is depolarized
by the passage of an electric current. This will then hopefully enable the Sinoatrial node (the heart‟s
normal pacemaker) or another intrinsic pacemaker to regain control of the heartbeat.
Indications of external Defibrillation (Asynchronous Mode)
• Ventricular fibrillation
It originates in the ventricles and in which multiple areas of the ventricle are depolarized and
repolarized independent of each other and this cause myocardial muscle fiber to contract in
chaotic rhythm that result in loss of synchronization and cardiac output and this result in
deprivation of tissues and organs from oxygen so hypoxia and acidosis will be developed. It
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5. characterized by: - Isoelectrical line. - Absent P, Q, R, S and T wave
• Ventricular tachycardia with cardiovascular collapse when synchronized cardioversion may
cause unacceptable delay
It is a rapid rhythm that originates in the ventricles characterized by:
- Wide and bizarre QRS.
- P wave may or may not be visible.
Contraindications of external Defibrillation
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Defibrillation is contraindicated in the treatment of Pulseless Electrical Activity (PEA),
such as idioventricular or ventricular escape rhythms
In the treatment of a systole
Factors affecting external defibrillation and cardioversion success
 Electrodes: The placement of defibrillation electrodes on the thorax, while determining
the transthoracic current pathway for external defibrillation, may have only a minimal
effect on the myocardial distribution of the 4 to 5 percent of energy that actually reaches
the heart.
 Electrode pad size: is an important determinant of transthoracic current flow during
external counter shock. A larger pad or paddle surface is associated with a decrease in
resistance and increase in current. Larger paddles may cause less myocardial necrosis when
repeated DC shocks are delivered to the chest wall. (Adult size is 8 -12 cm in diameter.)
 Waveforms: Most defibrillators are energy based; they charge a capacitor to a selected
voltage, and then deliver a preset amount of energy in joules as a monophasic waveform.
The energy delivered to the myocardium is dependent upon the selected voltage and the
transthoracic impedance.
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6.  Type of arrhythmia: The type of arrhythmia and the patient's clinical condition are
important determinants of defibrillation success. As an example, patients with ventricular
fibrillation as the primary event are easier to defibrillate than patients with secondary
ventricular fibrillation resulting from uncompensated congestive heart failure and
hypotension.
 Duration of arrhythmia: An additional factor of success in ventricular fibrillation is the
duration of the arrhythmia which is a determinant of the degree of organization of the
electrical impulse. The more recent the onset of ventricular fibrillation, the coarser are the
fibrillatory waves and the greater the success with defibrillation. As the arrhythmia
continues for a longer time (i.e., more than 10 to 30 seconds) the fibrillatory waves become
finer and the likelihood of successful termination decreases.
Special Considerations for Electrical Therapy:
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Early defibrillation is a high priority goal.
Dry the chest wall if wet or diaphoretic.
Remove medication patches.
Avoid placing the paddles/pads over a pacemaker or internal defibrillator.
If visible muscle contraction of the patient did not occur, defibrillation did not occur,
inspect equipment.
6. Avoid physical contact with patient during defibrillation/cardioversion.
7. Electrical therapy may not be successful in hypothermic patients; refer to hypothermia
protocol.
8. If a sinus rhythm is achieved by cardioversion and reverts to the previous rhythm, repeat
the cardioversion at the same setting as was initially successful
9. Clip/shave hair (if pads won‟t adhere)
10. Transcutaneous pacing may be performed in pulseless electrical activity.
Preparation for external defibrillation
1. Equipment
• Crush cart.
• Back board.
• E.C.G cable.
• Roll printer paper.
• K-Y gel or cotton with water
• Defibrillator with ECG.
• Bag valve mask for 100% oxygen
• Emergency suction and intubation equipment
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2. Prepare the patient
Place patient in safe environment (no water, metal).
Establish patent vein access.
The cardiac monitor for ventricular tachydysrhythmias.
Remove any Trans dermal medication) patches.
Remove all metallic objects from the patient and dentures.
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Place a back board under the patient in supine position
Vital signs with each significant change in ECG rate and rhythm
ECG for ventricular fibrillation
 Bring crush cart to bed or emergency drugs tray
 Initiate BLS
 Oxygenate the patient with bag valve device with 100% o2.
Procedure of external defibrillation
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Rationale & special
considerations
Call for help, begin cardiopulmonary resuscitation (CPR) and continue
until the caregivers arrive and set up the defibrillator
Attach electrocardiogram leads to the patient's chest. Turn on E.C.G
recorder for continuous printout
To maintain cardiac out
put
To establish a visual
recording of the
patient‟s current E.C.G
status and patient
response to intervention
Apply gel or paste to the defibrillator paddles, or two gel pads placed on the To avoid burning of
patient's chest.
skin, and to ensure easy
transmission of electric
current
The caregivers verify lack of a pulse, and select a charge.
To ensure diagnosis
Confirm shockable rhythm on monitor, check patient‟s pulse, run
For documentation
an ECG strip
To reduce transthoracic
resistance and enhance
electrical conduction
Apply conductive gel to the pt chest
(Use appropriate conductive agent)
7.
Place the synchronizer switch off (defibrillation mode)
8.
Select energy setting Shock for charging:
To increases the chance for
successful depolarization of
a. Adult Biphasic Defibrillation Settings (both Manual and cardiac muscle
AED):
i. Initial Defibrillations: 150 - 200 j
ii. Subsequent Defibrillations: 360 j
b. Adult monophasic Defibrillation Settings
i. Initial Defibrillations: 360 j
ii. Subsequent Defibrillations: 360 j
c. Pediatric Biphasic Defibrillation Settings: (< 8 years of age
and/or <55 Pounds)
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8. i. Manual Defibrillation: 2 -4 j/kg
ii. Subsequent Defibrillations: 6 j/kg
9.
Disconnect o2 source during actual defibrillation
10. Place paddles (8-12 cm in diameter) on chest one under right
clavicle, one in left anterior axillary line 5th inter costal space.
Two options exist for placement of paddles on the chest wall.
 First is the Anterolateral position in which a single paddle is
placed on the left fourth or fifth intercostal space on the
midaxillary line; the other paddle is placed just to the right of
the sternal edge on the second or third intercostal space
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The second option is the anteroposterior position. A
single paddle is placed to the right of the sternum, as
above, and the other paddle is placed between the tip of
the left scapula and the spine.
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To decrease risk of combustion
in the presence of electrical
current
To allow passing of electrical
current through the cardiac
muscle mass and to maximize
current flow through
myocardium
The paddles should be placed
firmly against the chest wall to
avoid arcing and skin burns.
Although there is a risk of
receiving a shock if touching
the patient or the stretcher, bed,
or other equipment in which
the patient is in contact, there
has been recent evidence that
continued contact with the
patient is safe during biphasic
defibrillation

9. To avoid impairment in
passage of the current to the
patient and malfunction or
damage of the device
 Pacemakers and ICDs should be at least 2.5 cm from direct
contact with paddles. (The anteroposterior approach is preferred
in patients with implantable devices to avoid shunting current to
the implantable device and damaging the system.)
 In women, place the apex paddle at the fifth to the six
intercostals space with the center of the paddle at the midaxillary
line
11. Apply pressure to each paddle against the chest wall
To avoid placement over a
women breast which increase
transthoracic resistance
If ICD is delivering shocks,
wait 30 – 60 sec before
defibrillating the patient
12. Check that no one is touching the patient, in contact with any
conductive material, or in contact with patient State “CLEAR”
loudly confirm rhythm
To decrease transthoracic
pressure for improving the
flow of electrical current across
the axis of the heart
To prevent the electric current
from conduction from the
patient to another individual
13. Verify that the patient is still ventricular fibrillation or pulse less
ventricular tachycardia patient
To ensure that the defibrillation
is necessary
14. Depress both red buttons simultaneously or press shock button
(hands free).
To depolarize the cardiac
muscle
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10. 15. Administer 2 minutes CPR (5 cycle)
To provide some coronary and
cerebral perfusion until
adequate heart function
resumes.
16. Reconfirm rhythm on monitor after a few seconds and assess for
carotid pulse, vital signs, and level of consciousness
17. Repeat the shock as prescribed if dysrhythmia still
After care
 After defibrillation, the patient's cardiac status, breathing, and vital signs are monitored
until he or she is stable. Typically, this monitoring takes place after the patient has been
removed to an intensive care or cardiac care unit in a hospital.
 Assess the level of consciousness of the patient every 15 minutes or according to his
condition.
 Oxygenate the patient with O2 mask.
 An electrocardiogram and chest x ray is taken.
 The patient's skin is cleansed to remove gel or paste, and, if necessary, ointment is
applied to burns.
 An intravenous line provides additional medication, as needed.
 Cleanse the paddles with water & soap.
 Keep the machine ready for reuse
Recording
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Rhythm before& after defibrillation.
Number (s) of attempts.
Joules used in each attempt.
Printout ECG tracing.
Patient response.
The timing of events and the treatments given.
When the code was initiated and when it was terminated
Names and signatures
Complications of external defibrillation:
 Skin irritation, redness, burns & muscle pain.
 VF or skin burns in bystanders.
 Dysrhythmias- a systole, bradycardia, AV block, VF following Supraventricular
tachycardia (SVT).
 Cardiac arrest and death.
 Cerebral anoxia and brain death.
 Embolic episodes.
 Electric accident.
 Myocardial damage.
 Hypotension.
 Pulmonary edema.
 Pacemaker or implantable Cardioverter – defibrillator dysfunction.
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11. 2. Automated external defibrillator (AED)
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AEDs are sophisticated, reliable, safe, computerized devices that deliver electric shocks
to victims of cardiac arrest when the ECG rhythm is one that is likely to respond to a
shock. Simplicity of operation is a key feature: controls are kept to a minimum, voice and
visual prompts guide rescuers. Modern AEDs are suitable for use by both lay rescuers
and healthcare professionals
Incorporate a simple ECG display.
Analyze ECG tracing & attempts to detect VT or VF.
Use a computerized diagnostic algorithm.
Most AEDs include a memory system to allow for post-event monitoring & review of
incidents.
Applied only to unresponsive, non breathing & pulseless patients.
Attached to patient using adhesive electrode pads.
CPR, transport, or any contact with patient should be avoided during analysis.
Types of Automated external defibrillator (AED): All AEDs analyze the victim‟s ECG
rhythm and determine the need for a shock
1- Semi- automated → Prompt user to deliver a shock.
2- Fully automated → automatically deliver shock itself.
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12. Internal defibrillation
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1. Direct Internal defibrillation
Delivering electric current through two cup-shaped paddles, these electrodes put surround
the sides of the heart and shock it directly.
Open-chest defibrillators generally require less energy to operate due to direct contact
with the heart as:
o Open thoracotomy approach.
o Open sternotomy approach.
Using special sterile internal paddles compatible with defibrillator.
One paddle is placed over right atrium or right ventricle.
Other paddle is placed over apex of the heart.
Energy for internal defibrillation
o 5 – 20 j for Biphasic defibrillator.
o 10 – 40 j Monophasic defibrillator.
2. Implantable Cardioverter defibrillator (ICD)
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13. 
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An implantable cardioverter defibrillator (AICD) is a device that is implanted in the chest
to monitor for and, if necessary, correct episodes of rapid heartbeat.
The implantable cardioverter defibrillator gets its name from the two functions that it
performs.
 First, the AICD sends small electrical charges to the heart to “reset” it when it
goes too fast. This process of converting one rhythm or electrical pattern to
another is called cardioversion.
 Second, the AICD will send stronger charges to “reset” the heart if it begins
quivering instead of beating. The act of stopping this potentially fatal quivering of
the heart (ventricular fibrillation) is called defibrillation.
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Although the main functions of the AICD are cardioversion and defibrillation, it can
also be programmed to do the following:
 Anti-tachycardia pacing. When an AICD senses a fast but rhythmic heartbeat
(tachycardia), it releases a series of precisely timed low-intensity electrical pulses
that gently interrupt the heart and allow it to return to a slower pace. Whereas
both cardioversion and defibrillation involve shocks that may feel like a sudden
kick in the chest, these low-intensity stimuli are generally not felt by the patient.
 Bradycardia pacing. Like an artificial pacemaker, the AICD can sense an
abnormally slow heartbeat (bradycardia) and send small electrical signals to pace
the heart until it restores and maintains a normal heart rate.
Modern AICDs can be programmed for all of the above functions. The AICD also records heart
activity and can transmit this information to the physician during a routine check, allowing the
physician to better diagnose and monitor the underlying conditions causing the patient‟s
arrhythmia.
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14. 
An AICD may be recommended for patients who have experienced any of the following:
 Previous heart attacks, with weakened functioning of the left ventricle. The
performance of the left ventricle is expressed numerically as the left ventricular
ejection fraction. It represents the proportion of blood in the heart that is pumped
out with each beat. A normal range is between 55 and 75 percent. An ejection
fraction below 40 percent has been shown to increase the risk of sudden cardiac
death. In heart attack survivors with reduced ejection fractions, it has been found
that an AICD plus Antiarrhythmic drugs significantly lowers the risk of sudden
cardiac death, as compared to Antiarrhythmic used alone.
 History of ventricular tachycardia (VT) or ventricular fibrillation (VF). For these
patients, AICDs have clearly improved survival compared to Antiarrhythmic
drugs.
 Coronary artery disease. Patients with coronary artery disease may have an
underlying arrhythmia. Studies have shown that, in patients with coronary artery
disease who received an AICD, cholesterol reducing drugs may have an antiarrhythmic effect that can reduce the recurrence of ventricular tachycardia or
ventricular fibrillation.
 Cardiac arrest.
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It is composed of pulse generator, lead system, and electrodes.
o Most modern AICDs use pulse generator contains capacitors, circuits & lithium
battery that need to be replaced every four to seven years, depending on how
often an electric shock is discharged
 Lead system inserted transvenously through subclavian or cephalic vein, positioned at
apex of right ventricle & superior vena cava.
 The doctor will use a programmer to change setting on ICD to allow therapy to be
individualized for each patient.
Complications of ICD
Although the insertion of an ICD requires only minor surgery, it still carries some risks. While
complications are rare, patients should report any of the following symptoms immediately:
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Redness, warmth, tenderness or swelling of the incision site, alone or with a fever.
Sometimes a hard ridge forms where the incision was closed. This will fade away as the
wound heals.
Drainage of liquid from the incision site, alone or with a fever.
Increased shortness of breath, prolonged hiccupping or difficulty breathing.
Fainting, lightheadedness or dizziness.
Fast or pounding heartbeats (palpitations).
Chest pain.
Re-experiencing the same symptoms that they had before surgery.
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15. Serious complications from the surgery occur in less than 1 percent of cases. These include:
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Severe bruising or bleeding
Formation of a blood clot
Torn blood vessel
Punctured lung or heart muscle
Stroke
Heart attack
Introduction of air into the space between the lung and chest wall
Death
The risk of having one of these complications is increased if people have certain characteristics,
such as the following:
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Advanced age
Obesity (more than 20 pounds heavier than one‟s ideal weight or body mass index 30 or
greater)
Severe lung disease (often due to smoking)
Use of various medications
Severely decreased heart function
II.
Cardioversion (Synchronized Cardioversion)
Definition:
Is the delivery of an electric shock through the chest wall in synchronization with the patient‟s
intrinsic „R wave‟ or QRS complex to terminate or convert the abnormal rhythm to sinus rhythm.
The goal of the electrical cardioversion
To safely and efficiently convert tachyarrhythmias causing hemodynamic compromise into sinus
rhythm through disrupt the abnormal electrical circuit(s) in the heart
Types of cardioversion: Cardioversion can be "chemical" or "electrical".
1. Chemical cardioversion:
Refers to the use of Antiarrhythmic medications to restore the heart's normal rhythm
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16. Cardioversion can be done using drugs that are taken by mouth or given through an intravenous
line .)It can take several minutes to days for a successful cardioversion)
Blood thinning medicines may be given with electrical cardioversion to prevent clots from
moving to the heart
2. Electrical cardioversion: (also known as “direct-current" or DC cardioversion); is a
procedure whereby a synchronized electrical shock is delivered through the chest wall to
the heart through special electrodes or paddles that are applied to the skin of the chest
and back.
Indications for synchronized cardioversion:
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Ventricular Tachycardia (VT) with pulse.
Supraventricular tachycardia SVT
Atrial fibrillation
Atrial flutter
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18. Contraindications: Contraindications include patients with
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Ventricular fibrillation
Known digitalis toxicity–associated tachycardia, patients with sinus tachycardia caused
by various clinical conditions, or patients with multifocal atrial tachycardia.
In addition, patients with atrial fibrillation are at risk for developing clots in the left
atrium that predispose to increased stroke risk. As a result, patients who are not
anticoagulated should not undergo cardioversion without a transesophageal echo that can
assess the presence of left atrial thrombus. (If emergency cardioversion necessary reduce
energy)
Equipment:
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Defibrillator with synchronizing capacity
Defibrillator pads: Self – adhesive
Paddles:
1. Adult size: (8-12 cm diameter) for patient weight > 10 kg
2. Pediatric size: (2.5 cm diameter) for patient weight < 10 kg
Emergency trolley with equipment
Bag and mask circuit
Suction equipment
IV access
Drugs as prescribed
Syringe and needles
Conductive material: Gel, paste or pads
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19. Patient preparation:
1. Informed consent should be done.
2. Baseline observations - BP pulse and ECG for post procedure comparison.
3. Be aware of the patient‟s serum K+ level or whether the patient has been digitalized.
Notify medical officer. (NB: Digitalis is usually discontinued 24-36 hours prior
cardioversion; its presence may result in an increased risk of cardioversion induced
arrhythmias).
4. Transesophageal echocardiogram (TEE) should be performed before the cardio version to
make sure there are no blood clots in the heart
5. Medication anticoagulant is usually given before elective cardioversion with 48 hr and
continues 4 weeks post procedure (I.V heparin may start to patient 24 -48 hr before the
procedure).
6. The patient should not eat or drink anything for 4 - 6 hours before the procedure.
7. The nurse should do pre-cardioversion teaching: Explain to the patient they will receive
intravenous sedation and will be drowsy throughout the procedure
o They will receive an electrical shock to restore the heart‟s normal rhythm
o They will sleep for a while after the procedure and may not remember anything
about the procedure when they wake up
o They will be transferred back to the Unit/Floor or discharged when fully awake
o If discharged home, they will require someone to take them home.
8. Put patient in supine position on hard surface (back board)
9. The patient is connected to the monitoring function of the defibrillator baseline rhythm
recorded; Lead selected for recording, Lead II.
10. An intravenous (IV) line is placed to deliver medications and fluids medications
11. Oxygen may be given through a face mask.
12. Combination of analgesia and sedation may be used as protocol.
13. Do not apply any lotion or ointments to chest or back before the procedure
14. Remove medication Trans dermal patches.
15. Prepare the skin by clipping the excessive hair at pads site.
16. Remove any metals and loose dentures.
Prepare self
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Wash hands
Wear gloves
Procedure
1.
2.
Rationale
If time permits and the patient is hemodynamically stable, correct
metabolic and electrolyte abnormalities
Connect patient to monitor and a rhythm strip obtained in order to
verify the type of tacky dysrhythmia the patient has. Is and this
arrhythmia may be mistaken for an artifact
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which may be the cause of the arrhythmia
Check to make sure that the patient has
pulse. Determine if he is it
hemodynamically stable. Rule out
hypotension, chest pain, altered mental
status, shortness of breath, shock or other
conditions which may be related to
tachycardia

20. 3.
4.
Select a monitor lead that display R wave of sufficient amplitude
(lead II)
Ensure airway management equipment is readily available (suction,
BVM, O2, laryngoscope, ETT, pulse ox, etc.)
To prevent deterioration of hemodynamic
stability that may be precipitated by
tachydysrhythmias
5.
Provide supplemental O2 and obtain IV access
6.
Use conscious sedation for the patient. As followed by
institution‟s protocol regarding conscious sedation
7.
Connect patient to monitor/defibrillator according to
manufacturers and institutional recommendations. Attach the
monitor leads (white to right, opposite is black, red to ribs) and
choose lead that gives the best R wave.
This will insure that Counter shock is
delivered during the QRS complex
8.
Engage synchronization button.
To prevent the random delivery of an
electric charge, which may potentiate
ventricular defibrillation
To decrease the risk of cerebral and
cardiac complications
To provide amnesia and decrease pain
during procedure
To signify the correct synchronization of
the defibrillator with the patient's ECG
rhythm.
9.
Look for markers on the R wave that would indicate a
synchronization mode. If necessary, adjust R wave gain control
until the synchronization markers occur with each QRS
complex
To achieve that the synchronization has
been achieved, observe for visual
flushing on the screen or listen for
auditory beeps
To activate the synchronization mode of
the defibrillator.
To deliver the current outside the heart's
vulnerable period
10. Select the proper energy level
No. of
attempt
First
Second
third
Stable
monomorphic VT
with pulse
100 j
200 j
300 j, then 360 j
Supra VT / and
Atrial flutter
Atrial
fibrillation
50 j
100 j
200 j, then 360 j
100 – 200 j
300 j
360 j
11. Apply the conductive medium to the patient and paddles
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This will prevent burns from the
electrical current and insure of passage of
the current through the cardiac muscle
mass
To reduce transthoracic resistance, thus
enhancing electric conduction through
subcutaneous tissue

21. 12. Positioned in paddles on the patient:
To maximize current flow through the
myocardium
 First (“sternum”) paddle: to the right of the upper
sternum and below the clavicle
 Second (“apex”) paddle: to the left of the nipple in the
midaxillary line, centered in the 5th intercostal space
13. Avoid placing both paddles next to one another on the anterior
 In women, place the apex paddle at the
fifth to the six intercostals space with
the center of the paddle at the
midaxillary line
 In the patient with a permanent
pacemaker, don‟t place paddles
directly over the pulse generator
(Anterior posterior placement)
 In the patient with temporary
pacemaker, turn off the pacemaker,
disconnect the lead wires, and use
standard paddle placement. (The
pacemaker wires should be insulated
with a rubber glove)
to prevent arching current
chest wall
14. Charge defibrillator paddles as prescribed
15. Disconnect oxygen source during actual cardioversion
To decrease the risk of combustion in the
presence of electric current
16. Ensure “all clear”
To maintain safety to caregivers
17. Push the charge button on the defibrillator and allow it to
Energy is not available until the
defibrillator is fully charged
charge
18. Apply firm downward pressure(25 pounds per square inch) on
paddles and press discharge buttons simultaneously after
ensuring everyone and equipment is “all clear” from the patient
19. The electrocardiogram recorder should be on
This decrease is intrathoracic resistance
and improves the flow of current across
axis of the heart.
This will establish a visual reporting and
permanent record of the patient and his
response to intervention
20. Check monitor, analyze rhythm, and reassess patient
21. If unsuccessful, press synchronization and increase the amount
of energy to be delivered.
22. To removing unwanted charge, press energy select
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If ventricular fibrillation or pulseless
ventricular tachycardia develops,
deactivate the synch button, and follow
the procedures for defibrillation

22. 23. Document the procedure in a clinical record is cardiac arrest
flow sheet
POST PROCEDURE:
1. Patient:
 The procedure will be terminated either by a successful reversion to sinus rhythm
or when the medical officer determines that cardioversion will not revert the
rhythm.
 Ensure the patient‟s airway is patent.
 Patient nursed in the left lateral position until fully conscious.
 Oxygen administration by mask at 6L/min.
 BP record immediately post procedure at 5 minute intervals for 15 minutes then
15minute intervals for 2 hours.
 A 12 lead ECG is recorded within an hour of the procedure.
2. Equipment
 Discard disposable equipments.
 Clean paddles.
3. Self
 Remove gloves.
 Hand washing.
Aftercare before discharge
 The patient generally wakes quickly after the procedure
 Medical personnel will monitor the patient's heart rhythm for a few hours, after which the
patient is usually sent home.
 The patient should not drive home; driving is not permitted for 24 hours after the
procedure.
Medications
 Antiarrhythmic medications, beta-blockers, digitalis, or calcium channel blockers may be
prescribed to prevent the abnormal heart rhythm from returning.
 Some patients may be prescribed anticoagulant medication, such as warfarin and aspirin,
to reduce the risk of blood it clots.
 The medications prescribed may be adjusted over time to determine the best dosage and
type of medication so the abnormal heart rhythm is adequately controlled
Discomfort
 Some chest wall discomfort may be present for a few days after the procedure.
 The doctor may recommend that the patient take an over-the-counter pain reliever.
 Skin irritation may also be present after the procedure. Skin lotion or ointment can be
used to relieve irritation.
Documentation
If applicable use the Conscious Sedation Protocol Form
In nursing notes or on special report sheet:
1. Date and time of procedure.
2. Pre and post procedure ECG
3. Procedure: patient tolerance, number of joules used for cardioversion and patient rhythm
before and after cardioversion.
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23. 4. Vitals before and after cardioversion.
5. Pre and post procedure observations
6. Oxygen therapy utilized during and after procedure.
7. Any additional therapy required.
8. Physicians present.
9. Anesthetic/sedative agent(s) given.
10. The condition of the skin following cardioversion
11. Rhythm strip before, during, and after cardioversion.
12. Document EKG lead used
Complications
General complications:
 The patient may become hypoxic or hypoventilate from sedation.
 Damage, bruising, burning or pain where the paddles were used.
 Allergic reactions from medicines used in pharmacologic cardioversion
 Blood clots that can cause a stroke or other organ
Cardiac complications:
 Hypotension
 Pulmonary edema
 Inducible arrhythmias include bradycardia, atrioventricular (AV) block, a systole,
VT, and VF. (In patients with acute coronary syndromes or acute myocardial
infarction, bradycardia or AV blocks can be induced, and they may need an
external or internal pacemaker. VT and VF commonly occur in patients with prior
similar history).
Electrical safety during defibrillation and cardioversion:
A) During the process of defibrillation:
3. Avoid placing excessive amount of conductive paste on the chest. This forms a
conductive bridge on the skin causing skin burns when defibrillator discharges.
4. Avoid using alcohol pads on the skin for defibrillation, electrical current passing through
the alcohol pads can burst into flames.
5. Avoid charging the defibrillator until ready to discharge the current.
6. Avoid placing the paddles near the monitoring electrodes to prevent sparks that causing
skin burns.
7. Do not tilt the paddles during use to avoid arching.
8. Stand clear from the patient and bed when discharging the device.
9. Do not make contact with any grounded object during operation of the defibrillation.
(B) During care of equipment:
1. Examine the paddles frequently especially for buildup of oxide film.
2. Do not discharge the paddles when pressed together.
3. Maintain the battery status of the device by keeping it plugged in during periods of
inactivity.
(C) In the environment:
1. Keep the area dry.
2. Disconnect electrical equipment from the patient.
Do not use a defibrillator in the presence of a flammable substance or anesthetic agents.
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