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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 blood leak detector faults on the PrismaFlex system. These faults typically indicate the system believes blood is present in the effluent line, which may be caused by actual membrane failure or more commonly by external factors such as sensor contamination, improper setup, or optical interference. This guide focuses on ruling out simple and verifiable causes first.
Step-by-Step Troubleshooting
Ensure Patient Safety First
- Confirm the device is not actively connected to a patient.
- If in use, ensure clinical staff has safely transitioned the patient to another machine before proceeding.
Verify the Alarm and Message Details
- Confirm the exact alarm text and when it occurs (startup, during therapy, or intermittently).
- This helps determine if the issue is setup-related or develops during operation.
Inspect the Effluent Line for Proper Installation
- Verify the effluent line is correctly routed through the blood leak detector.
- Ensure it is fully seated and aligned in the detector slot.
- Misalignment can cause false readings.
Check for Kinks, Air, or Improper Fluid Flow
- Inspect the effluent tubing for kinks or occlusions.
- Look for air bubbles or inconsistent flow.
- Irregular flow can interfere with optical detection.
Inspect the Effluent Fluid for Discoloration
- Check if the effluent appears pink or red (possible true blood leak).
- If discoloration is present, this may indicate a filter membrane failure rather than a sensor issue.
Clean the Blood Leak Detector Sensor Area
- Open the detector and inspect for residue, dried fluid, or condensation.
- Clean the optical surfaces using approved wipes (lint-free, non-abrasive).
- Even minor residue can interfere with light transmission.
Check for Moisture or Condensation
- Moisture inside the detector housing can cause false alarms.
- Allow the area to dry completely before retesting.
Verify Proper Cartridge/Filter Set Installation
- Ensure the correct cartridge is installed and fully seated.
- Improper seating can affect flow characteristics and detection accuracy.
Run a System Self-Test (If Available)
- Perform the PrismaFlex self-test or diagnostic check.
- Observe if the blood leak detector passes or fails during testing.
Swap with a Known Good Set (If Available)
- Replace the cartridge and effluent line with a known good setup.
- This helps isolate whether the issue is disposables-related versus device-related.
Observe for Recurring Alarms
- If the alarm persists after cleaning and setup verification, suspect sensor degradation or internal calibration issues.
If the Problem Persists
If all external causes (setup, contamination, disposables, and alignment) have been ruled out and the blood leak detector fault continues:
- Remove the device from service
- Label the device Out of Service
- Send for repair or further bench evaluation
At this point, the issue is likely due to internal sensor failure, optical component degradation, or calibration drift. Recognizing when external troubleshooting is complete is proper Clinical Engineering practice.
Clinical Use Tip
Always ensure the patient is safely disconnected or transitioned to another CRRT device before troubleshooting. Blood leak alarms can indicate real membrane failure, which is a patient safety risk and must be treated seriously until ruled out.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
“User reported blood leak alarm preventing therapy initiation on PrismaFlex.”
Cause
What was observed during troubleshooting.
Example:
“Dried effluent residue and moisture buildup observed in blood leak detector sensor causing false optical readings.”
Resolution
What action was taken.
Example:
“Cleaned and dried detector sensor area, verified proper tubing alignment, and tested unit. Alarm cleared and device returned to service.”
Helpful Details to Include (If Known)
- Effluent line properly seated and aligned
- Sensor cleaned and dried
- Cartridge/set swapped
- Effluent fluid appearance (clear vs discolored)
- Alarm timing (startup vs during therapy)
- Self-test results
- Final operational status
Final Thought
Blood leak alarms must always be approached with patient safety in mind, treating each as potentially real until proven otherwise. A structured approach—starting with setup, cleanliness, and flow—prevents unnecessary part replacement and downtime. Knowing when to escalate ensures both safety and efficiency while maintaining trust in the device.
That is successful troubleshooting.