NA ELECTRODE

Description of Event or Problem

THE INITIAL REPORTER RECEIVED QUESTIONABLE ISE INDIRECT NA AND K FOR GEN.2 RESULTS FROM MULTIPLE SAMPLES TESTED ON THE COBAS 6000 C 501 (UL) V. THE REPORTER STATED THAT SOME QUESTIONABLE INITIAL RESULTS WERE REPORTED OUTSIDE OF THE LABORATORY AND THE LOW ANION GAPS PROMPTED THE RERUN OF PATIENT SAMPLES. THE REPORTER WAS ABLE TO PROVIDE TWO PATIENT SAMPLES WITH DISCREPANT RESULTS: SAMPLE ID 0423:C02503S: THE INITIAL NA RESULT WAS 120 MMOL/L. THE REPEAT RESULT WAS 139 MMOL/L. SAMPLE ID 0423:C02514S: THE INITIAL NA RESULT WAS 127 MMOL/L. THE REPEAT RESULT WAS 138 MMOL/L.

Additional Manufacturer Narrative

THE ELECTRODE LOT NUMBER AND ITS EXPIRATION DATE WERE REQUESTED BUT NOT PROVIDED. THE INVESTIGATION IS ONGOING.

Additional Manufacturer Narrative

MEDWATCH FIELD D4 LOT NO WAS UPDATED. THE SERIAL NUMBER OF THE COBAS 6000 C501 (UL) V IS (B)(6). THE FIELD SERVICE ENGINEER (FSE) INSPECTED THE MODULE AND DID NOT FIND A SPECIFIC CAUSE FOR THE EVENT. HE THEN PREVENTATIVELY REPLACED ALL THE COMPONENTS TO THE ION-SELECTIVE ELECTRODE (ISE) MEASURING SYSTEM AND ALIGNED THE SIPPER NOZZLE AND ISE REAGENT PROBE. CALIBRATIONS, QCS, AND A 21-REPLICATE PRECISION TEST USING CONTROL MATERIAL WERE PERFORMED WITH SUCCESSFUL RESULTS. AFTER SERVICE, NO FURTHER ISSUES WERE REPORTED BY THE CUSTOMER. THE INVESTIGATION DETERMINED THE SERVICE ACTIONS VERIFIED THE MODULE'S PERFORMANCE.