SODIUM ELECTRODE

Additional Manufacturer Narrative

MEDWATCH FIELD D DEVICE IDENTIFICATION D4 SERIAL NO WAS UPDATED. QC AND CALIBRATION WERE PASSING AT THE TIME OF THE EVENT. A FIELD SERVICE ENGINEER (FSE) DETERMINED THAT A POOR CALIBRATION RESULTED IN QUESTIONABLE RESULTS. THE FSE PERFORMED AN ION-SELECTIVE ELECTRODE (ISE) RECALIBRATION AND PERFORMED A 21-CUP PRECISION CHECK WITH ACCEPTABLE RESULTS. THE CUSTOMER HAS NOT REPORTED ANY ADDITIONAL ISSUES SINCE THE SERVICE WAS COMPLETED. THE INVESTIGATION DETERMINED THAT THE SERVICE ACTIONS RESOLVED THE ISSUE. THE INVESTIGATION DID NOT IDENTIFY A PRODUCT PROBLEM. THE CAUSE OF THE EVENT COULD NOT BE DETERMINED.

Additional Manufacturer Narrative

THE COBAS C 303 ANALYTICAL UNIT SERIAL NUMBER IS (B)(6). THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THERE WAS AN ALLEGATION OF QUESTIONABLE SODIUM ELECTRODE RESULTS FROM THE COBAS C 303 ANALYTICAL UNIT FOR TEN PATIENTS. RESULTS WERE PROVIDED FOR TWO PATIENTS. PATIENT 1'S INITIAL RESULT WAS 129.8 MMOL/L. THE REPEAT RESULT ON ANOTHER ANALYZER WAS 135 MMOL/L. PATIENT 2'S INITIAL RESULT WAS 133 MMOL/L. THE REPEAT RESULT ON ANOTHER ANALYZER WAS 140 MMOL/L. THE INITIAL RESULTS WERE QUESTIONED BY THE CUSTOMER WHEN THEY NOTICED THAT THERE WAS A DISCREPANCY IN THE SODIUM RESULTS BETWEEN THE TWO ANALYZERS. NO QUESTIONABLE RESULTS WERE RELEASED OUTSIDE OF THE LABORATORY. THE REPEAT RESULTS WERE DEEMED TO BE CORRECT.