Patient Preparation, Positioning, and Electrode Placement
Domain 2 tests safe, reproducible patient preparation and accurate electrode placement, because small placement errors create large ECG changes.
Preparation and positioning
- Confirm order and two identifiers; explain the steps; ask the patient to empty the bladder if needed; provide privacy and keep the room warm.
- Position supine, arms relaxed at the sides, legs uncrossed, head supported. Ask the patient to breathe normally and stay still; avoid talking during acquisition.
- Expose only the needed areas. Clip excessive hair rather than shaving when possible; clean skin with alcohol or per manufacturer, let it dry, and abrade lightly only if policy allows. Avoid lotions, creams, and excessive gel.
Electrode locations for a 12-lead
- Limb leads: RA, LA, RL, LL on fleshy areas, usually just above wrists and ankles or as facility policy requires; avoid bone and joints.
- V1: 4th intercostal space, right sternal border. V2: 4th ICS, left sternal border. V3: midway between V2 and V4. V4: 5th ICS, midclavicular line. V5: 5th ICS, anterior axillary line. V6: 5th ICS, midaxillary line.
- For breast tissue, place V4–V6 on the chest wall, displacing tissue as needed; document any deviation.
- Amputation, bandages, or burns require an alternate site per policy, documented on the tracing.
Worked example
A patient has a right below-elbow amputation. The technician places RA on the right shoulder area per facility policy, documents RA right shoulder-amputation, and completes the tracing. Placing RA on the left arm would reverse lead I and mislead the clinician.
Traps
Placing V1 and V2 too high, mixing arm and leg leads, using bony prominences, failing to document alternate sites, and recording over clothing or lotion.