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What This Guide Helps With
This guide assists Clinical Engineering in troubleshooting Puritan Bennett 840 ventilators experiencing compressor failure or inadequate pressure delivery. These issues can prevent proper ventilation, trigger alarms, or compromise patient safety. Most causes are external or easily verifiable, such as power supply problems, tubing leaks, or obstruction, before assuming internal compressor failure.
Step-by-Step Troubleshooting
Verify Power and Electrical Connections
- Confirm the ventilator is plugged into a working, properly grounded outlet.
- Check the power cord for visible damage.
- Why: Inadequate voltage can reduce compressor output or prevent startup.
Check for Alarms or Error Messages
- Observe the ventilator display for specific pressure, flow, or compressor-related alarms.
- Document any error codes for reference.
- Why: This helps determine if the issue is detected by internal monitoring.
Inspect Circuit and Patient Tubing
- Ensure all inspiratory and expiratory tubing is properly connected and free of kinks.
- Check for any leaks at connections, humidifiers, or filters.
- Why: Leaks or obstructions can mimic compressor failure by preventing adequate pressure delivery.
Evaluate Filters and External Components
- Inspect and replace bacterial/HEPA filters if clogged.
- Verify the oxygen source or air supply line is functional.
- Why: Restricted airflow can reduce effective pressure output.
Run a Manual or Pre-Use Test
- Execute the ventilator’s built-in leak and pressure tests.
- Observe if the system can reach target pressures without a patient connected.
- Why: Confirms whether the problem is device-related or patient-circuit-related.
Listen and Observe Compressor Operation
- With the ventilator on, listen for unusual sounds (straining, failure to start, or irregular tone).
- Observe pressure waveforms on the display.
- Why: Audible or visual cues can help identify mechanical failure.
If the Problem Persists
If all external checks pass and the ventilator still fails to generate adequate pressure:
- Remove the ventilator from service immediately.
- Label it Out of Service.
- Send for bench evaluation or repair by a qualified biomedical engineer or manufacturer service.
Knowing when to escalate prevents patient risk and protects the device.
Clinical Use Tip
Do not attempt to ventilate a patient on a device showing inadequate pressure.
Move the patient to another ventilator before troubleshooting continues.
Ensure safety first: troubleshooting on a live patient is unsafe.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
Ventilator failing to achieve set inspiratory pressures; alarms triggered.
Cause
What was observed during troubleshooting.
Example:
External inspection revealed no tubing leaks; filters clear; compressor produces abnormal noise during test.
Resolution
What action was taken.
Example:
Ventilator removed from service, labeled Out of Service, and sent for manufacturer repair.
Helpful Details to Include
- Power outlet tested and verified
- Tubing connections inspected
- Filter status
- Alarms observed
- Compressor sounds or irregular operation
- Pre-use test results
- Final device status: Out of Service
Final Thought
Patient safety is paramount. A logical, stepwise approach ensures external issues are ruled out first, reducing unnecessary device disassembly. Proper documentation and timely escalation preserve both patient safety and ventilator longevity.
That is successful troubleshooting.