HEMOSIL SYNTHASIL

Additional Manufacturer Narrative

A REVIEW OF THE DEVICE HISTORY RECORD (DHR) AND CERTIFICATE OF ANALYSIS (COA) FOR HEMOSIL SYNTHASIL LOT N0451637 CONFIRMED THE LOT MET ALL MANUFACTURING AND RELEASE SPECIFICATIONS, WITH NO ABNORMALITIES IDENTIFIED. THE PACKAGE INSERTS FOR HEMOSIL NORMAL CONTROL 1 LOT N0351201 AND HEMOSIL ABNORMAL CONTROL 3 LOT N0552725 SPECIFY APTT ACCEPTANCE RANGES FOR THE ACL TOP FAMILY/ACL TOP FAMILY 50 SERIES ANALYZERS OF 24.3-32.3 SECONDS AND 47.5-64.3 SECONDS, RESPECTIVELY. QUALITY CONTROL (QC) STATISTICAL REPORTS FROM MAY 1, 2026, THROUGH MAY 14, 2026, WERE REVIEWED. FOR NORMAL CONTROL 1 (LOT N0351201), THE INTERVAL MEAN APTT WAS 27.9 SECONDS. ON (B)(6) 2026, A QC RESULT FAILED AT 15:37:41; REPEAT TESTING AT 18:03:48 AND 18:12:42 PRODUCED RESULTS WITHIN THE ESTABLISHED ACCEPTANCE RANGE. FOR ABNORMAL CONTROL 3 (LOT N0552725), THE INTERVAL MEAN APTT WAS 54.0 SECONDS. ON (B)(6) 2026, A QC RESULT OF 16.6 SECONDS WAS OBTAINED, APPROXIMATELY 9 STANDARD DEVIATIONS BELOW THE TARGET MEAN AND OUTSIDE THE ACCEPTANCE RANGE. REPEAT TESTING AT 18:03:41 AND 18:12:50 YIELDED RESULTS WITHIN RANGE. REVIEW OF THE SUBMITTED APTT DATA INDICATED THAT 11 OF 14 PATIENT SAMPLES WERE RE-TESTED TO VERIFY INITIAL RESULTS; 8 OF THESE REQUIRED NO CORRECTION. THREE SAMPLES REQUIRED RESULT CORRECTION WITH CLINICIAN NOTIFICATION DUE TO SIGNIFICANT DISCREPANCIES BETWEEN INITIAL AND REPEAT VALUES. FOUR SAMPLES WERE NOT REPEATED BECAUSE SPECIMEN AGE EXCEEDED THE VALIDATED APTT STABILITY WINDOW (4 HOURS). THERE WAS NO PATIENT IMPACT. NO SAMPLE REACTION CURVES OR INSTRUMENT BACKUP WERE PROVIDED FOR REVIEW, LIMITING THE ABILITY TO ASSESS SAMPLE-SPECIFIC VARIABLES OR OTHER CONTRIBUTING FACTORS. SERVICE HISTORY SHOWS THE USER CONTACTED WERFEN TECHNICAL SUPPORT REGARDING DISCREPANT APTT RESULTS. FIELD SERVICE PERFORMED VERIFICATION, INCLUDING INSPECTION OF PROBES AND VALVES; CLEANING OF PROBES AND SURFACES; LUBRICATION OF MECHANICAL RAILS; AND AIR/FD BLANKING UPDATES. THE INSTRUMENT PASSED FLUIDIC PRECISION, OCCLUSION, AND FLOW RATE TESTING. ERROR CODE 01156 (RACK CONTROLLER VOLTAGE OUT OF RANGE) OCCURRED TWICE DURING BLANKING. THE USER SUSPECTED POSSIBLE CONTAMINATION AND WAS ABLE TO RECOVER QC; THE SERVICE CALL REMAINED OPEN FOR FOLLOW-UP, AND NO ADDITIONAL ISSUES WERE REPORTED. A DEFINITIVE ROOT CAUSE OF THE ERRONEOUS APTT RESULTS COULD NOT BE DETERMINED. BASED ON THE AVAILABLE INFORMATION, IT IS POSSIBLE THAT REAGENT COMPONENTS WERE CONTAMINATED, POTENTIALLY DUE TO IMPROPER HANDLING OR STORAGE CONDITIONS. THE ISSUE WAS SUCCESSFULLY RESOLVED BY REPLACING THE AFFECTED REAGENT. THERE IS NO INDICATION OF A PRODUCT QUALITY ISSUE RELATED TO MANUFACTURING, DESIGN, OR LABELING. BASED ON THIS ASSESSMENT, NO FURTHER REMEDIAL ACTIONS ARE REQUIRED. THIS INCIDENT WILL BE MONITORED THROUGH TRENDING ANALYSIS.

Description of Event or Problem

ON (B)(6) 2026, THE CUSTOMER REPORTED THAT ERRONEOUS PROTHROMBIN TIME (PT) AND ACTIVATED PARTIAL THROMBOPLASTIN TIME (APTT) RESULTS WERE GENERATED USING HEMOSIL SYNTHASIL (LOT N0451637) ON AN ACL TOP 550 CTS (SN (B)(6)). THE ISSUE WAS IDENTIFIED FOLLOWING A SUDDEN DECREASE IN ABNORMAL LEVEL 3 QC VALUES FOR BOTH PT AND APTT ASSAYS. QUALITY CONTROL RESULTS WERE OUT OF RANGE, AND MULTIPLE PATIENT SAMPLES YIELDED UNEXPECTEDLY LOW VALUES, PROMPTING REPEAT TESTING OF 11 OF 14 PATIENT SAMPLES. AFTER REPLACING PT AND APTT REAGENTS, QC RESULTS RETURNED TO ACCEPTABLE RANGES; HOWEVER, 3 PATIENT RESULTS REQUIRED CORRECTION. THERE WAS NO IMPACT TO PATIENT OR PATIENT CARE.