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What This Guide Helps With
Clot or obstruction indications associated with specimen condition, sample devices, dried material, inlet contamination, cartridge fluidics, or internal flow problems.
Step-by-Step Troubleshooting
1. Protect Patient Testing
Do not continue using an analyzer that cannot reliably move patient samples through its fluid path. Redirect urgent specimens to another verified analyzer or approved laboratory testing method.
Do not repeatedly introduce the same clotted specimen.
Expected outcome: Clinical testing continues safely while the affected analyzer is evaluated.
2. Confirm the Reported Condition
Record the exact clot or obstruction message and determine when it occurs: during sample presentation, aspiration, analysis, or afterward.
Determine whether the condition occurred with one specimen or multiple specimens.
Expected outcome: The failure is clearly identified and its relationship to particular specimens is known.
If the condition occurred once with an obviously compromised specimen and subsequent approved verification is normal, troubleshooting can stop after required checks.
3. Inspect the Specimen
Examine the affected specimen and collection device for visible clotting, fibrin, dried blood, air, low volume, or delayed handling that could interfere with aspiration.
Do not attempt to mechanically break up or force a clotted specimen through the analyzer.
Expected outcome: The specimen is either confirmed suitable or identified as a likely external source of the obstruction indication.
If a replacement specimen processes normally and analyzer verification remains acceptable, troubleshooting can stop.
4. Inspect the Collection Device
Check the syringe, capillary tube, adapter, or other sample device for damaged openings, dried material, blocked tips, loose fittings, or debris.
Substitute an appropriate known-good device when available.
Expected outcome: The sample container and its outlet are unobstructed and capable of presenting the specimen normally.
If the problem follows the original collection device, remove that device from use and verify normal analyzer operation.
5. Inspect the Accessible Sample Inlet
With the analyzer safely idle, inspect the accessible inlet for visible dried blood or debris. Perform only approved external cleaning.
Do not probe into tubing or attempt to clear internal pathways using wires, needles, compressed air, or improvised flushing methods.
Expected outcome: The accessible sample interface is clean and unobstructed.
If approved cleaning restores normal operation, proceed to final verification.
6. Review GEM PAK Status
Check whether the clot or obstruction indication is accompanied by GEM PAK, fluid-path, or readiness messages.
Confirm the installed GEM PAK remains properly recognized and has not developed an obvious external leak or physical problem.
Expected outcome: The cartridge remains recognized and no external GEM PAK condition explains the obstruction.
If replacement of an externally defective or unacceptable GEM PAK is appropriate and resolves the problem, complete analyzer verification before returning it to service.
7. Verify With Approved Material
Use approved verification or quality-control material according to facility and manufacturer requirements to determine whether the analyzer can aspirate and process fluid normally.
Expected outcome: Fluid is aspirated and processed without another clot or obstruction indication.
If verification completes normally and required QC is acceptable, troubleshooting can stop.
8. Remove From Service for Recurrent Obstruction
If the obstruction recurs across acceptable specimens or approved test materials, stop external troubleshooting.
Do not disassemble the analyzer's fluid path or attempt internal flushing without authorized service instructions.
Expected outcome: A recurrent internal fluid-path condition is recognized as requiring qualified service.
If the Problem Persists
Common specimen, sample-device, inlet contamination, and cartridge-related external causes have been ruled out. The remaining problem may involve internal tubing, valves, pumps, pressure or flow sensing, cartridge fluidics, or another service-level fluid-handling condition.
The analyzer should be:
- Removed from service
- Labeled Out of Service
- Sent for repair or bench evaluation
- Evaluated using appropriate Werfen documentation and approved test equipment
- Repaired only by qualified personnel
After correction, complete required fluidic verification, quality-control checks, and return-to-service testing.
Knowing when to stop before invasive fluid-path work is proper troubleshooting.
Clinical Use Tip
Never force a visibly clotted specimen into the analyzer; recollection is safer than risking unreliable results or contaminating the sample pathway.
Work Order Documentation (CCR Method)
CCR = Complaint, Cause, Resolution
Complaint
What was reported by the clinical staff.
Example:
"Clinical staff reported repeated clot-detected messages while attempting to analyze blood gas specimens."
Cause
What was observed during troubleshooting.
Example:
"Clinical Engineering found the affected syringe contained visible clotting, while the analyzer processed approved verification material normally."
Resolution
What action was taken.
Example:
"Removed the compromised specimen from testing, confirmed normal analyzer aspiration and required QC performance, and returned the analyzer to service."
Helpful Details to Include (If Known)
- Exact clot or obstruction message
- Number of affected specimens
- Visible specimen condition
- Collection device type and condition
- Sample inlet condition
- GEM PAK status
- Whether approved verification material was tested
- Whether the obstruction recurred
- QC results after troubleshooting
- Final analyzer status
Final Thought
Protect patient testing, inspect the specimen and collection device first, and verify the accessible inlet and cartridge before assuming an internal obstruction. Recurrent fluid-path faults require proper escalation and documented return-to-service verification.
That is successful troubleshooting.