SODIUM ELECTRODE

Additional Manufacturer Narrative

THE COBAS 6000 C (501) MODULE SERIAL NUMBER IS (B)(6). THE CUSTOMER REPORTED THAT QC WAS WITHIN SPECIFICATIONS BUT HAD SHIFTED SLIGHTLY. THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THERE WAS AN ALLEGATION OF A QUESTIONABLE SODIUM ELECTRODE RESULT FROM THE COBAS 6000 C (501) MODULE FOR ONE PATIENT. THE INITIAL RESULT WAS 128 MMOL/L; THE REPEAT RESULT ON ANOTHER ANALYZER WAS 139 MMOL/L. THE INITIAL RESULT WAS REPEATED AS IT WAS QUESTIONED BY THE PHYSICIAN.

Additional Manufacturer Narrative

THE CALIBRATION AND QC WERE BOTH IN RANGE PRIOR TO THE EVENT. A FIELD SERVICE ENGINEER (FSE) DETERMINED THAT THERE WAS NO ISSUE FOUND. THE FSE PERFORMED AN OVERALL CHECK OF THE SYSTEM, VERIFIED THAT THE SYRINGE SEALS WERE NOT WORN, THAT THE ION-SELECTIVE ELECTRODE (ISE) SIPPER NOZZLE AND ISE PROBE WERE CLEAN WITH NO BENDS. THE SAMPLE PROBE WAS CLEAN AND NOT BENT. THE FSE VERIFIED THE RINSE LEVELS AND THAT THEY WERE WITHIN THE PROPER RANGES. THE GEAR PUMP WAS SET ON THE HIGH SIDE, AND THE SYRINGE TUBING WAS IN GOOD CONDITION WITHOUT ANY KINKS. HE ALSO INSPECTED THE ELECTRODES, AND THE REFERENCE ELECTRODE HAD SOME SALT BUILDUP; IT WAS CLEANED AND PLACED BACK IN. FOR VERIFICATION CALIBRATION, QC, AND A 21-CUP PRECISION CHECK WERE COMPLETED. THE CUSTOMER STATED THAT AFTER INSPECTING THE TUBE OF THE SAMPLE IN QUESTION, GEL WAS SITTING AT AN ANGLE, AND THEY SAW A POSSIBLE PLATELET, BUT WERE UNABLE TO REMOVE IT. THE SAMPLE WAS RESPUN AND RERAN ON THE C501'S. ADDITIONAL RESULTS WERE NOT PROVIDED. THE INVESTIGATION DETERMINED THAT THERE WAS NO CAUSE FOUND, AND THE INSTRUMENT'S PERFORMANCE WAS VERIFIED AND THE ISSUE APPEARS TO BE RESOLVED.