Electrocardiogram (ECG)
An ECG is a test that records the electrical activity of the heart.
The ECG is used to measure the rate and regularity of heartbeats, the size and position
of the chambers, the presence of damage to the heart, and the effects of drugs or devices
used to regulate the heart, like a pacemaker.
A resting 12-lead EKG is an important diagnostic test that shows heart activity at rest. It is noninvasive and completely painless. It does not require the patient to perform any activity. It may also take place as part of an exercise or chemical stress test to increase heart activity and look for problems. Correct lead placement plays a vital role in obtaining accurate results.
Electrode placement
RA -On the right arm, avoiding thick muscle.
LA -In the same location that RA was placed, but on the left arm.
RL -On the right leg, lateral calf muscle
LL -In the same location that RL was placed, but on the left leg.
V1 -In the fourth intercostal space (between ribs 4 & 5) just to the right of the sternum (breastbone).
V2 -In the fourth intercostal space (between ribs 4 & 5) just to the left of the sternum.
V3 -Between leads V2 and V4.
V4 -In the fifth intercostal space (between ribs 5 & 6) in the mid-clavicular line.
V5 -Horizontally even with V4, in the anterior axillary line.
V6 -Horizontally even with V4 and V5 in the midaxillary line.
Steps to Performing the ECG:
(a) Ask the patient to undress to the waist with pants legs rolled up and hosiery removed. The patient may wear a gown if desired.
(b) Ask the patient to lie on her back. Expose the chest in sections as you apply the electrodes.
(c) Apply the right and left arm electrodes anywhere on the arms between the shoulder and the wrist. Make sure they stay away from any bony prominences. Clean the skin and apply contact gel if necessary as you apply each electrode.
(d) Apply the leg electrodes in the same way.
(e) Locate the patient's right clavicle, place...