On this page
Asset Type
Manufacturer
Model
What This Guide Helps With
This guide assists Clinical Engineering in troubleshooting situations where a ResMed Lumis ventilator delivers inconsistent pressure or tidal volumes. Symptoms may include patient alarms for high or low pressure, tidal volume deviation, or noticeable fluctuations in delivered breaths. The guide emphasizes simple, external checks before assuming internal device failure.
Step-by-Step Troubleshooting
Verify Power and Battery Status
- Ensure the device is powered on and the battery is sufficiently charged.
- Low power can cause inconsistent operation.
- Check that the AC adapter is properly connected if the device is plugged in.
Inspect Circuit and Connections
- Examine all tubing, humidifier connections, and masks for kinks, bends, or obstructions.
- Ensure connectors are fully seated and compatible with the Lumis system.
- Even minor disconnections can cause pressure or volume inconsistencies.
Check for Mask Fit and Leak
- Verify that the mask is properly fitted to the patient.
- Large leaks can result in inaccurate tidal volume delivery.
- Swap with a known good mask if issues persist.
Evaluate Filters and Humidifier
- Check and replace any clogged or wet filters.
- Inspect the humidifier chamber for water levels and secure connections.
- Malfunctioning humidifiers can alter flow resistance.
Verify Ventilator Settings
- Confirm that pressure and volume settings match the patient’s prescribed therapy.
- Look for accidental mode changes or parameter adjustments.
Observe Patient Interface and Compliance
- Check for sudden changes in patient effort, airway resistance, or compliance.
- Document any patient-related factors that could affect delivered volumes.
Perform a Quick Functional Test
- Using a test lung or ventilator simulator, verify consistent pressure and tidal volume delivery.
- If normal on a test lung, the issue may be patient-related rather than device-related.
If the Problem Persists
If external checks fail to resolve inconsistencies, the ventilator should be:
- Removed from service
- Labeled Out of Service
- Sent for vendor repair or bench evaluation
Clinical Engineering should not attempt internal board-level repairs. Knowing when to escalate is critical for patient safety.
Clinical Use Tip
Do not troubleshoot the device on an active patient if possible.
Switch the patient to a backup ventilator first.
Ensure all interventions maintain uninterrupted patient support.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
“Patient alarms indicate inconsistent tidal volume and pressure delivery.”
Cause
What was observed during troubleshooting.
Example:
“External circuit leak detected at mask interface; filter partially clogged; settings verified as correct.”
Resolution
What action was taken.
Example:
“Adjusted mask fit, replaced filter, verified proper delivery with test lung. Patient returned to therapy.”
Helpful Details to Include
- Outlet and power source tested
- Cables and tubing connections verified
- Alarm behavior recorded
- Indicator lights normal
- Unusual sounds absent
- Final device status: operational or Out of Service
Final Thought
Patient safety is paramount. Use a logical, stepwise approach starting with external checks. Escalate to repair only after ruling out simple causes. Document all observations and actions clearly to support future troubleshooting and continuous quality improvement.
That is successful troubleshooting.