12-Lead EKG Electrode Placement

• Proper electrode placement is crucial for accurate 12-lead EKGs
• Misplacement leads to incorrect interpretations, false ST-elevation, as well as misdiagnosed arrhythmias

General Preparation

• Ensure skin preparation by cleaning with alcohol wipes to remove oils, sweat and dirt
• Shave or trim hairy areas where electrodes will be placed
• Dry the skin before attaching electrodes
• Avoid bony prominences and muscle movement
• Place electrodes over flat, fleshy areas to minimize artifact from movement

Limb Lead Placement (RA, LA, RL, LL)

• Mnemonic: "White on Right, Smoke (Black) over Fire (Red), Clouds (White) over Grass (Green)"
• RA (Right Arm): Place on the right wrist or shoulder
• LA (Left Arm): Place on the left wrist or shoulder
• RL (Right Leg): Place on the right lower leg or lower abdomen
• LL (Left Leg): Place on the left lower leg or lower abdomen
• If the patient is trembling, move limb leads closer to the torso to reduce artifact
• Do not cross the midline when placing limb leads; left-side leads stay on the left, and right-side leads stay on the right

Precordial (Chest) Lead Placement (V1−V6)

• Mnemonic: "V1 and V2, Right and Left of Sternum, V4 Nipple, V6 Side"
• V1: 4th intercostal space, right of the sternum
• V2: 4th intercostal space, left of the sternum
• V3: Midway between V2 and V4
• V4: 5th intercostal space, midclavicular line
• V5: Level with V4, anterior axillary line
• V6: Level with V4 and V5, midaxillary line
• Find the 4th intercostal space first by feeling the sternal notch (Angle of Louis) and counting down
• Ensure even spacing between V4, V5, and V6 to avoid false readings
• In large-breasted patients, lift the breast and place V4-V6 on the chest wall underneath the breast tissue, not on top
• With barrel-chested or COPD patients, leads may need slight adjustments due to anatomical variations, but avoid shifting leads too high or low

Troubleshooting Poor Readings

• Artifact Issues: Ensure leads are securely attached and not loose
• Reduce muscle tremors by having the patient relax their arms and legs
• Check for lead reversals; an inverted P-wave in lead I or abnormal aVR can indicate misplacement
• Electrical Interference: Ensure patient is not touching metal objects such as bed rails or stretchers
• Move away from strong electrical sources like monitors and ventilators

Special Considerations

• Right-Sided EKG (RV MI or Inferior STEMI suspected): Move V4 to the right side of the chest (V4R, 5th intercostal space, midclavicular line)
• Posterior EKG (Posterior MI suspected): Move V4, V5, and V6 to the posterior chest (V7, V8, V9)
• Pediatric Considerations: Place limb leads on the torso instead of arms/legs to reduce artifact
• Obese Patients: Ensure electrodes make good skin contact; place slightly higher if necessary to avoid skin folds

Double-Check

• Confirm all leads are in the correct position
• Look for common errors like limb lead reversal and chest lead misplacement
• Always obtain a clean baseline before printing the EKG