Common Mistakes: Performing a 12-Lead EKG
These are the specific ways this task goes wrong on the job — not hypothetical edge cases, but patterns that cause real documentation errors, billing problems, or patient safety issues.
Swapping the right-arm and left-arm leads, which produces a tracing that looks like a serious cardiac abnormality (lead reversal) when nothing is actually wrong.
Placing V1/V2 in the wrong intercostal space, which alters the chest lead morphology enough to affect interpretation.
Not cleaning oily or diaphoretic skin before placing electrodes, causing a poor-contact, artifact-heavy tracing.
Letting the patient talk or shiver during the recording without addressing it, instead of pausing to fix the cause of the artifact.
How the Quality Checkpoints Prevent These
Every mistake above is caught by one of this task's quality checkpoints — the habit of checking these consistently is what actually prevents the error, not just knowing it exists.
- ✓
All 10 electrodes are placed at the correct anatomical landmarks, not approximate locations.
- ✓
Skin prep (cleaning, occasional shaving) is done at each site to ensure good electrical contact.
- ✓
The patient is instructed to stay still and quiet during the recording.
- ✓
The tracing is reviewed for obvious artifact or lead reversal before the patient is released.
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