ROCHE 9180 ELECTROLYTE ANALYZER

Additional Manufacturer Narrative

THE SODIUM ELECTRODE LOT NUMBER WAS 31244847. THE FIELD SERVICE ENGINEER FOUND THAT THE CUSTOMER WAS NOT PERFORMING MAINTENANCE CORRECTLY AS THEY IMMERSED THE REFERENCE ELECTRODE IN INDUSTRIAL GRADE HYPOCHLORITE AND THE PROBE WAS NOT CLEANED ACCORDING TO LABELING. THE CUSTOMER WAS RECEIVING FROZEN SAMPLES FROM REGIONAL OFFICES AND PROCESSING WAS CARRIED OUT DIRECTLY FROM THE MOTHER TUBE AFTER THAWING, WITHOUT CENTRIFUGATION. THE ENGINEER TOOK A PATIENT'S SAMPLE, CENTRIFUGED IT, AND PROCESSED IT FOUR TIMES WITH FULLY REPRODUCIBLE RESULTS.

Description of Event or Problem

THE INITIAL REPORTER STATED THEY RECEIVED QUESTIONABLE RESULTS FOR AN UNSPECIFIED NUMBER OF PATIENT SAMPLES TESTED ON A ROCHE 9180 ELECTROLYTE ANALYZER. RESULTS FROM THE ANALYZER DID NOT AGREE WITH THE CLINICAL CONDITION OF PATIENTS. THE CUSTOMER PROVIDED DATA FOR ONE PATIENT SAMPLE WITH DISCREPANT SODIUM ELECTRODE RESULTS. THE SAMPLE INITIALLY RESULTED IN A SODIUM VALUE OF 128.5 MMOL/L. THE SAMPLE WAS REPEATED TWICE, RESULTING IN VALUES OF 134.3 MMOL/L AND 137.5 MMOL/L.

Additional Manufacturer Narrative

THE SODIUM ELECTRODE LOT NUMBER AND EXPIRATION DATE WERE REQUESTED, BUT NOT PROVIDED. A ROCHE REPRESENTATIVE VISITED THE CUSTOMER AND NOTED THE CUSTOMER MAINTAINED THE INSTRUMENT POORLY. THE INVESTIGATION IS ONGOING.

Additional Manufacturer Narrative

A REVIEW OF CERTIFICATES OF ANALYSES FOR THE ELECTRODE AND SYSTEM REAGENT LOT NUMBERS CONFIRMS THAT ALL COMPONENTS PASSED THE INTERNAL MANUFACTURING AND QUALITY CONTROL CHECKS, MEETING ALL REQUIRED SPECIFICATIONS. CALIBRATION DATA WAS ACCEPTABLE. QUALITY CONTROLS RUN ON 10-JUL-2025 WERE ACCEPTABLE FOR THE FIRST CONTROL LEVEL. LEVEL 2 WAS OUTSIDE OF RANGE FOR NA AND K, BUT THEN SUBSEQUENTLY WERE BACK WITHIN RANGE WHEN TESTED LATER THAT SAME MORNING. LEVEL 3 CONTROLS WERE MEASURED TWICE AND EACH TIME, THE K AND CL VALUES WERE OUTSIDE OF RANGE. BASED ON THE PROVIDED PRINTOUTS, THE LAST 10 QC MEASUREMENTS WERE WITHIN THE EXPECTED RANGE. THE INVESTIGATION DETERMINED THE ISSUE IS CONSISTENT WITH PROTEIN CONTAMINATION DUE TO THE CUSTOMER'S INCORRECT MAINTENANCE AND PRE-ANALYTICAL PROCEDURES. THE CUSTOMER WAS IMMERSING THE REFERENCE ELECTRODE IN INDUSTRIAL-GRADE HYPOCHLORITE AND NOT CLEANING THE NEEDLE ACCORDING TO THE USER MANUAL. ADDITIONALLY, THEY WERE PROCESSING FROZEN SAMPLES THAT WERE THAWED AT ROOM TEMPERATURE WITHOUT BEING RE-CENTRIFUGED, AND WERE PROCESSING SAMPLES DIRECTLY FROM THE MOTHER TUBE INSTEAD OF A SEPARATE SAMPLE CONTAINER. THESE PRACTICES CAN LEAD TO PROTEIN BUILD-UP ON THE ELECTRODES, CAUSING UNSTABLE AND INACCURATE RESULTS. THIS IS SUPPORTED BY THE FACT THAT WHEN THE ENGINEERING TEAM FOLLOWED CORRECT PROCEDURES, THE RESULTS WERE REPRODUCIBLE.