On this page
Asset Type
Electrocardiograph (EKG) Machine
Manufacturer
Model
What This Guide Helps With
Troubleshooting unstable ECG waveforms, lead-off indications, excessive artifact, or poor signal caused by electrodes, cables, patient preparation, positioning, or environment.
Step-by-Step Troubleshooting
1. Protect the Patient and Confirm Monitoring Needs
Do not troubleshoot an unreliable ECG acquisition system while clinical decisions depend on the affected tracing. If an accurate ECG is immediately required, move the patient to another verified ECG device before continuing.
Confirm whether the problem affects all leads, specific leads, every patient, or only one acquisition.
Expected outcome: Patient care continues safely and the exact signal-quality complaint is identified. If another verified device provides an acceptable ECG, continue evaluating the MAC 7 outside active patient dependence.
2. Inspect the Patient Electrodes
Check that all electrodes are properly attached, within usable condition, and making complete contact with prepared skin. Replace loose, dried, contaminated, damaged, or questionable electrodes.
Verify that excessive hair, moisture, lotion, poor skin contact, or patient movement is not interfering with electrode adhesion.
Expected outcome: Electrodes remain securely attached and lead-off indications or artifact disappear. If the ECG becomes stable, troubleshooting can stop after final verification.
3. Verify Lead Placement and Connections
Confirm correct electrode placement and verify each lead wire is connected to the intended electrode. Reseat connections at the electrodes, lead set, patient cable, and acquisition module as applicable.
Look for partially seated connectors or connections placed under mechanical strain.
Expected outcome: All intended leads are recognized and stable waveforms are present. If normal acquisition returns, proceed to functional verification.
4. Inspect the Lead Set and Patient Cable
Inspect accessible cables and connectors for cuts, crushed areas, exposed conductors, bent contacts, fluid contamination, loose strain reliefs, or intermittent connections.
Gently reposition the cable while observing a test acquisition. Do not aggressively flex or manipulate damaged wiring.
Expected outcome: Cable movement does not create lead-off conditions or waveform disturbances. A cable that causes repeatable instability should be removed from use.
5. Substitute Known-Good External Accessories
If compatible approved accessories are available, substitute a known-good lead set, patient cable, or acquisition module one item at a time.
Avoid changing several components simultaneously because doing so can obscure the actual cause.
Expected outcome: The signal becomes stable when the defective external accessory is replaced. If so, remove the faulty accessory from service and stop troubleshooting after verification.
6. Check Patient Movement and Environmental Interference
Confirm that patient motion, muscle tremor, nearby powered equipment, poorly routed cables, or other environmental conditions are not contributing to artifact.
Keep patient cables appropriately positioned and separated from obvious interference sources where practical.
Expected outcome: The tracing remains stable under normal acquisition conditions. If eliminating an environmental cause restores acceptable ECG quality, troubleshooting can stop.
7. Review Accessible ECG Settings
Verify that the selected acquisition mode and accessible ECG settings are appropriate for the intended exam. Do not make undocumented configuration changes merely to mask persistent artifact.
If a setting was unintentionally changed, restore the approved clinical configuration.
Expected outcome: The MAC 7 acquires the intended ECG without abnormal signal degradation or persistent lead-off indications.
8. Perform Final Functional Verification
Using an approved ECG simulator or other appropriate test method, verify that all expected ECG channels acquire consistently and that no intermittent lead-off or artifact condition remains.
Check both displayed and recorded ECG output as applicable.
Expected outcome: Stable simulated waveforms are acquired across the intended leads without unexpected artifact or lead-off indications. The device may be returned to service if all required checks pass.
9. Escalate an Unresolved Signal Problem
If poor signal continues with verified electrodes, correct placement, known-good external cables/accessories, appropriate settings, and a simulator, stop external troubleshooting.
Expected outcome: The device is removed from clinical use and routed for bench evaluation rather than being returned with an unresolved ECG acquisition problem.
If the Problem Persists
Common external causes have been ruled out. Remaining possibilities may include an acquisition-interface problem, internal signal-processing fault, connector damage, configuration issue, or another service-level condition.
The MAC 7 should be:
- Removed from service.
- Labeled Out of Service.
- Sent for repair or bench evaluation.
- Evaluated using appropriate GE Healthcare documentation and approved test equipment.
- Repaired or configured only by qualified personnel.
After corrective work, complete appropriate ECG functional testing and any required electrical or performance verification before return to service. Knowing when to stop external troubleshooting is proper troubleshooting.
Clinical Use Tip
When ECG quality is questionable, obtain the clinically necessary tracing on another verified device rather than allowing troubleshooting to delay patient assessment.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Clinical staff reported persistent artifact and intermittent lead-off indications during 12-lead ECG acquisition."
Cause
What was observed during troubleshooting.
Example:
"Clinical Engineering found a damaged patient lead set that produced intermittent signal loss when the cable was repositioned."
Resolution
What action was taken.
Example:
"Replaced the defective lead set with an approved known-good accessory and verified stable ECG acquisition on all intended leads using an ECG simulator."
Helpful Details to Include (If Known)
- Leads affected.
- Whether the condition occurred on one or multiple patients.
- Electrode condition and placement.
- Patient cable and lead-set condition.
- Known-good accessories tested.
- Whether movement affected the problem.
- Environmental conditions observed.
- Simulator test results.
- Results before and after correction.
- Final device status.
Final Thought
Patient safety comes first. Rule out electrodes, placement, cables, accessories, positioning, settings, and environmental causes before assuming an internal ECG acquisition failure. Verify the correction and document the complaint, cause, and resolution clearly.
That is successful troubleshooting.