On this page
Asset Type
Manufacturer
Model
What This Guide Helps With
This guide assists Clinical Engineering in troubleshooting DASH 3000 Series monitors when SpO₂ readings are incorrect, fluctuating, or missing entirely. Common symptoms include the monitor showing unusually high or low oxygen saturation values, no reading displayed, or alarms for “SpO₂ sensor fault.” The guide focuses on external checks first, avoiding unnecessary internal repairs.
Step-by-Step Troubleshooting
Verify the patient connection and sensor placement
- Ensure the SpO₂ sensor is properly attached to the patient’s finger, toe, or earlobe.
- Check that the sensor is aligned correctly and not wrapped too tightly.
- Why: Poor contact or movement can cause false or absent readings.
Inspect the sensor for damage
- Look for cracks, frayed cables, or discolored sensors.
- Replace the sensor with a known-good unit if any damage is observed.
- Why: Damaged sensors often trigger false readings or fail to communicate with the monitor.
Check the SpO₂ cable and connector
- Disconnect and reconnect the cable to ensure a secure connection.
- Swap with a tested cable if available.
- Why: Loose or damaged cables can prevent the monitor from receiving accurate signals.
Assess patient-related factors
- Check for nail polish, artificial nails, cold extremities, or excessive motion.
- Consider repositioning the sensor or moving it to a different site.
- Why: These factors can interfere with the sensor’s light absorption, causing inaccurate readings.
Verify monitor settings
- Confirm the SpO₂ module is enabled in the monitor configuration.
- Ensure appropriate averaging time and alarm limits are set.
- Why: Incorrect settings may prevent the monitor from displaying valid SpO₂ values.
Power cycle the monitor
- Perform a controlled reboot by following the monitor’s power-down procedure.
- Reattach the sensor after restart.
- Why: Temporary software glitches can affect SpO₂ processing.
Test with a known-good patient simulator or test sensor
- If available, connect a pulse oximeter tester to verify the monitor’s SpO₂ module.
- Why: Confirms whether the monitor module is functioning correctly independent of the patient.
If the Problem Persists
After completing the above steps, if readings remain false or absent:
- Remove the monitor from service.
- Label it Out of Service.
- Send it for internal bench evaluation or manufacturer repair.
Reminder: Knowing when to escalate is proper Clinical Engineering practice.
Clinical Use Tip
Do not rely on faulty readings for patient care. Move the patient to another monitor if necessary.
Troubleshoot only when it is safe to do so and avoid adjustments during critical patient interventions.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
“Patient monitor showing missing or false SpO₂ readings.”
Cause
What was observed during troubleshooting.
Example:
“Sensor cable worn and loose; sensor improperly attached to patient.”
Resolution
What action was taken.
Example:
“Replaced sensor and reconnected cable; verified accurate readings; patient monitored safely.”
Helpful Details to Include
- Outlet tested: N/A (monitor powered, display functional)
- Cables swapped: Yes, verified good cable
- Alarm behavior: SpO₂ sensor fault alarm present intermittently
- Indicator lights: Sensor indicator blinking red
- Unusual sounds or heat: None
- Final device status: Returned to service with verified readings
Final Thought
Patient safety depends on reliable SpO₂ monitoring. A systematic approach—from checking the sensor and cables to verifying settings—ensures accurate readings and avoids unnecessary internal repairs. Always document your findings clearly and escalate when external causes are ruled out.
That is successful troubleshooting.