ECG Recording, Equipment Operation, and Troubleshooting
Domain 3 covers equipment readiness, standard calibration, acquisition, and artifact troubleshooting.
Before recording
- Inspect cables, lead wires, electrodes, paper, and battery; confirm machine settings: 25 mm/s paper speed and 10 mm/mV gain unless ordered otherwise.
- Enter patient data accurately; select the correct lead set; ensure filters are at facility default.
Artifact and fixes
- Somatic tremor: muscle tension, shivering, talking-warm the room, relax the patient, reposition.
- 60-cycle AC interference: thick, fuzzy baseline-check nearby electrical devices, cable loops, electrode contact, and grounding.
- Wandering baseline: respiration, movement, poor adhesion, lotion-re-prep skin, secure electrodes, ask the patient to stay still.
- Flat line in one lead: check that electrode and lead wire; all leads flat: check the patient, connections, power, and cable.
- Interrupted tracing: loose wire, paper jam, low battery.
Worked example
A tracing shows a thick, fuzzy baseline across all leads at 60 cycles per second. The technician checks that the patient is not touching metal, moves a nearby infusion pump cord, re-preps a loose LL electrode, and repeats. The tracing clears. The technician does not change gain or paper speed to fix the appearance without an order and documentation.
Traps
Ignoring artifact; failing to verify calibration; using damaged cables; not documenting settings or deviations; repeating until the tracing looks normal.