2. OUTLINE
• What is 12 lead ECG
• Purpose of doing 12 Leads ECG
• Indications
• Contraindications
• Components of ECG machine
• Item preparation
• How to perform ECG
• How to minimize interference
• References
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7. WHAT IS 12 LEAD ECG
•12 lead ECG is the representation of the heart’s
electrical activity.
•Sees heart from 12 different view.
•Placed on patient’s skin and on the surface of chest.
•Electrodes are conductive pad in contact with the
body.
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8. WHAT IS 12 LEAD ECG
• Consists of :
- 3 standard limb leads (bipolar)
- 3 augmented limb leads (unipolar)
- 6 precordial chest leads (unipolar)
*Electrocardiogram Augmented Limb Leads (Unipolar)
These are termed unipolar leads because there is a
single positive electrode that is referenced against a
combination of the other limb electrodes.
* The positive electrodes for these augmented leads are
located on the left arm (aV L ), the right arm (aV R ), and
the left leg (aV F ).
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12. PURPOSE OF DOING 12 LEAD
ECG
•Identify primary conduction abnormalities (cardiac
arrhythmias, cardiac hypertrophy, pericarditis,
electrolytes imbalance, ischemic changes and
myocardial ischemia site and the extent of
myocardial infarction).
•Monitoring recovery from MI.
•Evaluate effectiveness of cardiac medication.
•Asses Pacemaker performance.
•Determine effectiveness of thrombolytic therapy.
•Baseline pre operative assessment.
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13. INDICATIONS
•Chest pain, epigastric pain
•Back, neck, jaw or arm pain without chest pain
•Palpitations
•Syncope or near syncope
•Exertional dyspnea, weakness
•Diaphoresis
•Feel anxiety
•Electrolyte imbalance
•Sign of tachycardia, bradycardia, shock
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15. CONTRAINDICATIONS
•Patients allergies of sensitivity to the ECG patch or
the electrode gel
•Patient refuse
•No absolute contraindication to 12 Lead ECG
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22. 1. Ensure the patient is reclined in a comfortable
resting position
2. Use A High Quality ECG Electrode
3. Ensure The Correct Electrode Placement
4. Record In A 4 x 3 Format
5. Record Any Clinical Signs During The Procedure
6. Remove The Electrodes After Use
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23. BEFORE ECG PROCEDURE
PREPARATION OF EQUIPMENT
•Machine is charged and ready to use.
•It should be stock with sufficient paper for recording,
tissues and clinical wipes.
•Cable is attached firmly and no frayed, broken or
bare cable wire.
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24. BEFORE ECG PROCEDURE
SKIN PREPARATION
•Dry the skin if moist or diaphoretic
- Alcohol swab to remove excess skin oil
- Clip or shave excess hair
- Abrade dead skin with skin prep tape
- Check lead wires for damage/wear
- Ensure leads are not dried out
- Promote an environment that prevents the
patient from sweating profusely.
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26. BEFORE ECG PROCEDURE
•Ask patient to remove/ loosen jewelleries and
undergarment.
•Patient’s arm should be lying flat at each side, relax
the shoulders and keep legs uncrossed.
•If the bed did not fit comfortably with patient, ask
patient to cross his arms on his stomach to reduce
muscle tension and movement.
•Instruct patient to lie still and quietly and to breathe
normally until the test is done.
•Place a cover over the chest area.
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27. DURING ECG PROCEDURE
•Select flat ,fleshy areas to place limb electrode.
•Avoid muscular and bony area.
•If patient has amputated limb, choose a site on the
stump.
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28. DURING ECG PROCEDURE
•Place electrodes correctly.
•Placement as follows:
- V1 – 4th intercostal space on the RT sternum
- V2 – 4th intercostal space on the LT sternum
- V3 – Midway between V2 and V4
- V4 – 5th intercostal space at the mid clavicular line
- V5 – Anterior axillary line, same horizontal level of V4
- V6 – Mid axillary line , same horizontal level as V4
and V5.
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29. 12 LEADS ECG PLACEMENT
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32. •Record an ECG:
- Turn on ECG machine.
- Calibrate to 10mm/mV.
- Rate at 25mm/s.
- Enter ID.
- Record and print.
•Remove the electrodes and clean patients skin
•CLEAN and DRY the electrodes
•Assist patient to a comfortable position
•Put away ECG machine in equipment room, charge.
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34. •Cause of artifact/ interference:
- Contact (skin, leads, faulty wires)
- Movement (Patient, cable, vehicle)
•Ensuring good contact.
•Prevent patient movement.
- Check for subtle movement.
- Look for muscle tension.
- Coach/instruct the patient.
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35. HOW TO MINIMIZE
INTERFERENCE
•Prevent cable movement.
•Switch off non essential electrical devices and
equipment within the vicinity if possible.
•Check for cable loops and avoid running cable
adjacent to metallic objects
•Inspect wires and cable for cracks or breaks.
Replaced as needed.
•Ensure securely connection between patient cable
and the ECG device.
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36. REFERRANCE
1. European Heart Journal (2010) 31, 243–259
doi:10.1093/eurheartj/ehp473.
2. Understanding 12leads ECG, Nursing 2018.
3. Utility of the Pre-Hospital 12 Lead ECG, Dr. Mike Lewell, Dr. Matthew
Davis (November 4, 2011)
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