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Asset Type
Continuous Renal Replacement Therapy (CRRT)
Manufacturer
Model
What This Guide Helps With
This guide assists Clinical Engineering in troubleshooting effluent scale or weight sensor calibration errors on the PrismaFlex system. These errors may present as inaccurate fluid balance readings, calibration failures, or alarms preventing therapy initiation. The focus is on identifying external factors such as improper setup, scale obstruction, or environmental influences before assuming internal sensor failure.
Step-by-Step Troubleshooting
Ensure Patient Safety First
- Ensure the system is not connected to a patient before troubleshooting
- Calibration and scale checks must be performed safely
Verify Device is Not in Active Patient Use
- Confirm the system is not actively delivering therapy
- Do not attempt calibration during patient treatment
Check for Obstructions on the Effluent Scale
- Confirm nothing is touching or resting on the effluent scale except the designated effluent bag
- IV tubing, cables, or contact with the machine frame can affect readings
- Even slight contact can cause calibration errors
Inspect Effluent Bag Placement
- Ensure the effluent bag is properly hung on the correct hook
- Ensure it is freely hanging without touching the pole or floor
- Ensure it is not overfilled or improperly positioned
Check for Residual Fluid or Debris on the Scale Platform
- Look for dried fluid, debris, or residue on the scale surface
- Clean if necessary
- Uneven surfaces can affect weight accuracy
Verify Scale is Level and Machine Position is Stable
- Ensure the PrismaFlex is on a flat, stable surface
- Uneven flooring or movement can impact weight readings
- Lock the wheels to prevent shifting
Perform a System Restart
- Power cycle the unit to reset the scale system
- Allow full boot-up before reattempting calibration
Run Scale Calibration per On-Screen Prompts
- Ensure all scales are empty when prompted
- Do not touch or disturb the machine during calibration
- Watch for any interruptions or error messages
Check for Environmental Interference
- Evaluate for vibration from nearby equipment (beds, pumps)
- Check for airflow from vents causing bag movement
- Ensure no staff contact during calibration
Inspect Cable Connections (External Only)
- If accessible without disassembly, verify that external connectors related to the scale are secure
- Do not open panels or access internal components
Test with Known Empty and Loaded Conditions
- Confirm the system reads zero with no load
- Add a known weight (if available) to verify reasonable accuracy
If the Problem Persists
If calibration errors continue after completing all external checks, common setup and environmental causes have been ruled out. The issue is likely due to internal scale or sensor failure.
- Remove the device from service
- Label Out of Service
- Send for repair or further bench evaluation
Recognizing when the issue is beyond external correction is proper Clinical Engineering troubleshooting.
Clinical Use Tip
Never troubleshoot or recalibrate scales while the device is actively treating a patient. Inaccurate fluid balance can directly impact patient safety. Always transition the patient to a properly functioning device first.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
“Unit alarming for effluent scale calibration failure; unable to start therapy.”
Cause
What was observed during troubleshooting.
Example:
“No external obstructions found; calibration repeatedly failed despite proper setup and stable environment, indicating likely internal scale fault.”
Resolution
What action was taken.
Example:
“Removed unit from service, labeled out of service, and sent to vendor/biomed shop for scale evaluation and repair.”
Helpful Details to Include (If Known)
- Effluent bag properly hung and not touching surfaces
- Scale platform clean and unobstructed
- Unit on level surface with wheels locked
- Calibration attempted multiple times
- Environmental factors ruled out (vibration, airflow)
- Alarm messages or error codes recorded
- Final device status (removed from service)
Final Thought
Effluent scale accuracy is critical to safe CRRT therapy. Always approach troubleshooting by ruling out simple physical and environmental factors first. When calibration cannot be achieved, escalation is the correct and safe decision. Proper documentation ensures continuity and supports effective repair.
That is successful troubleshooting.