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What This Guide Helps With
This guide addresses the ↑O2% alarm, which indicates the measured oxygen concentration is higher than the set FiO₂. This condition can result in unintended hyperoxia and inaccurate oxygen delivery.
Step-by-Step Troubleshooting
1. Ensure Patient Safety First
- Assess patient oxygenation status immediately
- Reduce FiO₂ if clinically appropriate
- Prepare backup ventilation if needed
2. Verify the Reported Alarm and Behavior
- Confirm ↑O2% alarm is displayed
- Compare measured vs set FiO₂
- Determine if alarm is persistent or intermittent
3. Check Oxygen Supply Source (Most Common Cause)
- Verify correct gas connections (O₂ vs air)
- Confirm proper wall outlet usage
- Check supply pressures are within normal range
4. Perform Oxygen Sensor Calibration
- Initiate calibration per device procedure
- Use stable room air or 100% O₂ source
- Follow all on-screen prompts fully
5. Inspect for Environmental or Circuit Influences
- Check for leaks or improper circuit setup
- Ensure no external oxygen is introduced into the circuit
- Verify humidifier and accessories are correctly configured
6. Re-evaluate Ventilator Settings
- Confirm set FiO₂ matches intended therapy
- Adjust settings if clinically appropriate
7. Stop When Resolved
- Confirm measured FiO₂ stabilizes
- Ensure alarm does not recur
- Return device to service if stable
If the Problem Persists
If the ↑O2% alarm continues after calibration and all external causes are ruled out, this indicates a likely oxygen sensor failure or internal gas control issue.
- Remove the device from service
- Label as Out of Service
- Send for repair or bench evaluation
Clinical Use Tip
Never troubleshoot on an active patient. Move the patient to a backup ventilator before continuing diagnostics.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Ventilator alarming ↑O2% with measured FiO₂ higher than set value during patient use."
Cause
What was observed during troubleshooting.
Example:
"Oxygen sensor drift causing inaccurate FiO₂ measurement confirmed by failed calibration."
Resolution
What action was taken.
Example:
"Performed calibration attempt; alarm persisted. Removed ventilator from service and sent for repair."
Helpful Details to Include (If Known)
- Alarm behavior
- Accessories swapped
- Power behavior
- Environmental factors
- Indicator lights
- Final device status
Final Thought
Oxygen accuracy is critical for safe ventilation. Always verify external causes first, ensure accurate measurement, and escalate promptly when readings cannot be trusted.
That is successful troubleshooting.