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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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Objectives:

After review and study of these pages and attendance at an approved nursing skills lab the

critical care student should be able to:

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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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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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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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

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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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:

1. Early defibrillation is a high priority goal.

2. Dry the chest wall if wet or diaphoretic.

3. Remove medication patches.

4. Avoid placing the paddles/pads over a pacemaker or internal defibrillator.

5. 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

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 Rationale & special

considerations

1. Call for help, begin cardiopulmonary resuscitation (CPR) and continue

until the caregivers arrive and set up the defibrillator

To maintain cardiac out

put

2. Attach electrocardiogram leads to the patient's chest. Turn on E.C.G

recorder for continuous printout

To establish a visual

recording of the

patient‟s current E.C.G

status and patient

response to intervention

3. Apply gel or paste to the defibrillator paddles, or two gel pads placed on the

patient's chest.

To avoid burning of

skin, and to ensure easy

transmission of electric

current

4. The caregivers verify lack of a pulse, and select a charge. To ensure diagnosis

5. Confirm shockable rhythm on monitor, check patient‟s pulse, run

an ECG strip

For documentation

6. Apply conductive gel to the pt chest

(Use appropriate conductive agent)

To reduce transthoracic

resistance and enhance

electrical conduction

7. Place the synchronizer switch off (defibrillation mode)

8. Select energy setting Shock for charging:

a. Adult Biphasic Defibrillation Settings (both Manual and

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)

To increases the chance for

successful depolarization of

cardiac muscle

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i. Manual Defibrillation: 2 -4 j/kg

ii. Subsequent Defibrillations: 6 j/kg

9. Disconnect o2 source during actual defibrillation To decrease risk of combustion

in the presence of electrical

current

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

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.

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

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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

To avoid impairment in

passage of the current to the

patient and malfunction or damage of the device

To avoid placement over a

women breast which increase

transthoracic resistance

If ICD is delivering shocks,

wait 30 – 60 sec before

defibrillating the patient

11. Apply pressure to each paddle against the chest wall To decrease transthoracic

pressure for improving the

flow of electrical current across

the axis of the heart

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 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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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 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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2. Automated external defibrillator (AED)

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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Internal defibrillation

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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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.

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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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 anti-

arrhythmic effect that can reduce the recurrence of ventricular tachycardia or

ventricular fibrillation.

Cardiac arrest.

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:

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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Serious complications from the surgery occur in less than 1 percent of cases. These include:

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:

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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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:

Ventricular Tachycardia (VT) with pulse.

Supraventricular tachycardia SVT

Atrial fibrillation

Atrial flutter

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Contraindications: Contraindications include patients with

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:

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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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

Wash hands

Wear gloves

Procedure Rationale 1. If time permits and the patient is hemodynamically stable, correct

metabolic and electrolyte abnormalities which may be the cause of the arrhythmia

2. 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

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

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3. Select a monitor lead that display R wave of sufficient amplitude

(lead II)

4. 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 To decrease the risk of cerebral and

cardiac complications 6. Use conscious sedation for the patient. As followed by

institution‟s protocol regarding conscious sedation

To provide amnesia and decrease pain

during procedure

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 signify the correct synchronization of

the defibrillator with the patient's ECG

rhythm.

To achieve that the synchronization has

been achieved, observe for visual

flushing on the screen or listen for

auditory beeps 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 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

Stable

monomorphic VT

with pulse

Supra VT / and

Atrial flutter

Atrial

fibrillation

First 100 j 50 j 100 – 200 j

Second 200 j 100 j 300 j

third 300 j, then 360 j 200 j, then 360 j 360 j

11. Apply the conductive medium to the patient and paddles 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

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12. Positioned in paddles on the patient:

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

To maximize current flow through the

myocardium

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)

13. Avoid placing both paddles next to one another on the anterior

chest wall

to prevent arching current

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

charge

Energy is not available until the

defibrillator is fully charged

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

This decrease is intrathoracic resistance

and improves the flow of current across

axis of the heart.

19. The electrocardiogram recorder should be on 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.

If ventricular fibrillation or pulseless

ventricular tachycardia develops,

deactivate the synch button, and follow

the procedures for defibrillation 22. To removing unwanted charge, press energy select

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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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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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