Asset Type

Ventilator

Manufacturer

ResMed

Model

Lumis

What This Guide Helps With

This guide assists Clinical Engineering in troubleshooting mask or circuit leak detection errors on a ResMed Lumis ventilator. Symptoms may include alarms or messages indicating “mask leak,” “circuit leak,” high leak values, or inconsistent pressure/volume delivery. The focus is on verifying external connections, mask fit, and circuit integrity before considering internal device issues.

Step-by-Step Troubleshooting

Verify Patient Safety First

• Ensure the patient is stable and has an alternate ventilator or oxygen support available if necessary.
• Do not troubleshoot on an active patient without backup support.

Check the Mask Fit

• Inspect the mask for proper sizing and fit on the patient.
• Ensure straps are correctly adjusted, not twisted, and headgear is not overly tight or loose.
• Small leaks around the mask are a common cause of alarm triggers.

Inspect Circuit Connections

• Confirm that all tubing and connectors between the ventilator and mask are securely attached.
• Check for cracks, holes, or worn areas in the tubing.
• Reconnect any loose components to ensure airtight connections.

Examine Humidifier and Accessory Interfaces

• If using a humidifier or heated circuit, ensure it is properly seated and not introducing leaks.
• Inspect O-rings or gaskets for integrity.

Assess Exhalation Port and Filters

• Make sure exhalation ports are clear and filters are clean.
• Blocked or dirty ports can cause false leak readings.

Run a Device Leak Test

• If the device has a built-in circuit/mask leak test function, perform the test according to prompts.
• Observe reported leak values; compare to expected baseline for the mask type.

Swap Components if Needed

• Replace the mask or circuit with a known-good component to see if the error persists.
• This isolates whether the issue is with the device or the consumables.

If the Problem Persists

If mask fit, circuit integrity, and accessories are verified and alarms persist:

• Remove the device from service.
• Label as Out of Service.
• Send for vendor repair or internal bench evaluation.

Avoid further use on patients until resolved, reinforcing patient safety and proper troubleshooting discipline.

Clinical Use Tip

Always prioritize patient safety by moving the patient to another ventilator if a leak issue is suspected. Troubleshoot externally visible leaks first before escalating. Document observed leak levels and any component swaps for continuity of care.

Work Order Documentation (CCR Method)

CCR = Complaint, Cause, Resolution

Complaint

What was reported by the clinical staff.

Example:
“Mask leak alarm keeps triggering during patient use.”

Cause

What was observed during troubleshooting.

Example:
“Observed loose mask straps and minor tubing crack causing intermittent circuit leak.”

Resolution

What action was taken.

Example:
“Adjusted mask fit, replaced damaged tubing, performed leak test confirming normal leak values.”

Helpful Details to Include

• Mask type and size
• Circuit tubing serial numbers or condition
• Leak values displayed
• Alarm frequency and pattern
• Any humidifier or accessory in use

Final Thought

Proper mask and circuit leak troubleshooting ensures accurate ventilation, prevents false alarms, and protects patient safety. Following logical, external-first checks and escalating when necessary preserves equipment integrity and supports consistent patient care.

That is successful troubleshooting.