On this page
Asset Type
Manufacturer
Model
What This Guide Helps With
This guide assists Clinical Engineering in troubleshooting situations where a Jaeger Medical Vyntus pulmonary function testing system produces inaccurate spirometry values, lung volume measurements, or inconsistent patient test results.
Inaccurate pulmonary measurements are often caused by external factors such as improper calibration, incorrect ambient condition inputs, contaminated flow sensors, leaks in the breathing circuit, or incorrect accessory setup before assuming internal hardware failure.
Pulmonary function systems rely on precise calibration and environmental compensation to ensure measurement accuracy. Incorrect environmental data, calibration errors, or airflow disturbances can significantly affect readings.
Step-by-Step Troubleshooting
Ensure Patient Safety First
- Confirm the device is not currently in use on a patient.
- Ensure the pulmonary test has been stopped and the patient is disconnected before performing troubleshooting.
- Pulmonary measurements must not be altered while connected to a patient.
Verify daily calibration was performed
- Confirm that the system completed its required daily calibration or volume verification using the calibration syringe.
- Look for calibration pass/fail indicators.
- Check for deviations beyond acceptable limits.
- Spirometry systems typically require accuracy within approximately ±3% of the calibration syringe value.
- If calibration has not been performed, perform a full calibration procedure.
- Re-run verification after completion.
- Incorrect calibration factors can directly produce incorrect patient measurement values.
Verify correct calibration syringe use
- Ensure the correct calibration syringe is used and that it is functioning properly.
- Check the 3-liter syringe integrity.
- Verify there are no leaks.
- Confirm smooth piston movement.
- A damaged or leaking calibration syringe will introduce measurement errors during verification.
Check ambient environmental data
- Confirm that the system is using correct environmental inputs.
- Verify room temperature, relative humidity, and barometric pressure.
- If the Vyntus system uses an ambient sensor module, ensure it is connected and functioning.
- If entered manually, confirm values are accurate.
- Incorrect ambient data can lead to incorrect lung volume calculations.
- Verify the ambient sensor is not located near heating vents, in direct sunlight, or near airflow sources.
Inspect the pneumotach or flow sensor
- Examine the airflow sensor assembly.
- Check for condensation, debris, contamination, or physical damage.
- Moisture or condensation inside flow sensors can alter airflow measurements and produce inaccurate spirometry results.
- If contamination is present, clean the reusable components according to manufacturer guidelines.
- Replace disposable filters or flow sensors if applicable.
Check patient circuit components
- Inspect all patient interface components.
- Verify the correct mouthpiece is installed.
- Ensure the MicroGard or filter is properly attached.
- Confirm tubing connections are fully seated.
- Check for cracks or leaks in the tubing.
- Small leaks in the breathing circuit can produce inaccurate lung volume readings and inconsistent spirometry curves.
- Replace disposable components if there is any uncertainty.
Verify proper system warm-up and stability
- Ensure the system has stabilized before calibration or testing.
- Environmental pressure fluctuations, vibration, or room disturbances can affect calibration stability and measurement accuracy.
- Confirm the system has been powered on long enough to stabilize.
- Ensure the room environment is stable during testing.
Review recent maintenance or configuration changes
- Determine whether the issue began after software updates, flow sensor replacement, hardware module replacement, or relocation of the system.
- Incorrect configuration or incomplete initialization can produce abnormal readings.
- Restart the system software and re-run calibration if needed.
Perform verification testing
- Run a verification test using the calibration syringe.
- Observe repeatability of measurements.
- Check variance between trials.
- Confirm whether readings fall within acceptable tolerance.
- If results remain inconsistent across repeated trials, suspect sensor or module failure.
If the Problem Persists
If the system continues to produce inaccurate spirometry or lung volume measurements after completing the checks above, the issue may involve flow sensor failure, pneumotach damage, ambient sensor malfunction, gas analyzer or measurement module failure, or internal system calibration drift.
At this point the device should be removed from service, labeled Out of Service, and evaluated on the bench or sent to the manufacturer or authorized service provider.
Recognizing when external causes have been ruled out and escalation is required is part of proper troubleshooting.
Clinical Use Tip
Never troubleshoot pulmonary function equipment while connected to a patient.
If inaccurate measurements are suspected during testing:
- Stop the test immediately.
- Move the patient to another calibrated pulmonary function system.
- Troubleshoot the device after the patient has been safely disconnected.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
“Respiratory Therapy reported spirometry results from Vyntus system appeared inconsistent and lower than expected across multiple patients.”
Cause
What was observed during troubleshooting.
Example:
“Inspection found condensation and debris within the pneumotach flow sensor and calibration verification failing outside acceptable tolerance.”
Resolution
What action was taken.
Example:
“Flow sensor cleaned and disposable filter replaced. Full system calibration performed with 3-L syringe. Verification test passed within acceptable limits and system returned to service.”
Helpful Details to Include (If Known)
- Calibration verification results
- Ambient temperature / pressure readings
- Condition of flow sensor or pneumotach
- Disposable component replacement
- Presence of condensation or contamination
- Calibration syringe condition
- Number of verification trials performed
- Final device status
Final Thought
Pulmonary function testing equipment relies on extremely precise airflow and volume measurements. Small issues such as condensation, incorrect calibration, environmental data errors, or minor circuit leaks can significantly affect diagnostic results. A structured troubleshooting process that verifies calibration, environment, sensors, and patient interface components helps ensure accurate testing and protects patient care.
That is successful troubleshooting.