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17
Connection of the Limb Electrodes
4 electrodes of 10 ECG electrodes are attached to the limbs. Reference lead is the electrode connected
onto the right leg.
Before connecting electrodes:
1- Prepare the patient‟s skin.
■ The skin is a poor conductor of electricity, therefore preparation of the patient's skin is important to
facilitate good electrode contact to skin.
■ Wash sites thoroughly with soap and water.
2- Apply some gel on the skin of these sites.
3- Place the electrode on proper site of the patient body.
The limb electrodes of 12-lead ECG should be placed in the following sites:
Left arm (LA)
Right arm( RA)
Left leg ( LL)
Right leg (RL)
Figure 2-7 Connection of the Limb Electrodes