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Manufacturer
Model
What This Guide Helps With
Identifies causes of inaccurate FVC/FEV1 values due to technique, contamination, calibration issues, or environmental factors affecting ultrasonic measurement.
Step-by-Step Troubleshooting
Ensure Patient Safety First
- Confirm the device is not actively being used on a patient.
- Move testing to another spirometer if needed.
Verify Reported Inaccuracy
- Confirm what is incorrect:
- FVC or FEV1 lower or higher than expected
- Inconsistent results between tests
- Repeat a test using a simulator or known subject if available.
Check Patient Technique (If Reported During Use)
- Confirm proper testing technique:
- Tight seal around mouthpiece
- No air leaks
- Proper nose clip use
- Full inhalation and forceful exhalation
Inspect Flow Tube / Mouthpiece
- Check for:
- Moisture or condensation
- Debris, mucus, or residue
- Cracks or damage
- Replace with a new or known-good flow tube/mouthpiece.
Check for Environmental Factors
- Evaluate testing environment:
- Strong airflow (fans, vents) near device
- Extreme temperature or humidity changes
- Relocate device to a stable environment if needed.
Perform Device Calibration Verification (if applicable)
- Verify if the device requires calibration checks per facility protocol.
- Perform a calibration check using a known calibration syringe if supported.
Verify Device Settings and Patient Profile
- Check:
- Correct patient demographics (age, height, gender)
- Correct test type selected
Restart Device
- Power cycle the device completely.
If the Problem Persists
If all external causes have been ruled out, the issue is likely related to internal ultrasonic sensor drift or device processing errors.
Remove the device from service, label it Out of Service, and send it for repair or bench evaluation.
Clinical Use Tip
Never troubleshoot accuracy issues on an active patient. Always move the patient to a verified working device before evaluating performance concerns.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Staff reported inconsistent and inaccurate FVC/FEV1 readings compared to previous patient baselines."
Cause
What was observed during troubleshooting.
Example:
"Moisture and residue contamination found in the flow tube affecting ultrasonic measurement accuracy."
Resolution
What action was taken.
Example:
"Replaced flow tube and verified accurate readings with repeat testing."
Helpful Details to Include (If Known)
- Flow tube condition checked/replaced
- Calibration verification performed
- Patient technique reviewed
- Environmental conditions assessed
- Device restarted
- Consistency of readings before/after intervention
- Final device status
Final Thought
Accurate spirometry depends heavily on external factors such as patient technique, clean airflow paths, and proper setup. Clinical Engineering should always rule out these variables before suspecting internal failure. Removing a device from service when accuracy cannot be verified protects patient safety and maintains clinical trust.
That is successful troubleshooting.