BEUDAMED
    FDA Adverse Event Malfunction Summary report: N

    PULSE GEN MODEL 103

    MDR report key: 2245770 · Received August 24, 2011

    Report

    Report Number
    1644487-2011-01978
    Event Type
    Malfunction
    Date Received
    August 24, 2011
    Date of Event
    July 4, 2011
    Report Date
    July 25, 2011
    Manufacturer
    CYBERONICS INC
    Product Code
    LYJ
    PMA / PMN Number
    P970003
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    IN, US
    Reporter Occupation
    OTHER

    Narratives

    Additional Manufacturer Narrative · 1

    ANALYSIS OF PROGRAMMING HISTORY. THE BATTERY ASSOCIATED WITH THIS GENERATOR MAY HAVE BEEN AN OUTLIER IN TERMS OF THE BATTERY IMPEDANCE THAT IS EXPERIENCED AT THE BEGINNING OF BATTERY LIFE.

    Description of Event or Problem · 1

    FURTHER INFORMATION REVEALS THE PATIENT HAS A CONSULT FOR THE PAINFUL STIMULATION ISSUE AND A DECISION WILL BE MADE ON HOW TO PROCEED. ATTEMPTS FOR FURTHER INFORMATION HAVE BEEN UNSUCCESSFUL TO DATE.

    Description of Event or Problem · 1

    IT WAS REPORTED THAT THE PT STARTED FEELING PAINFUL STIMULATION AT GENERATOR SITE A FEW WEEKS PRIOR. PT'S CURRENT SETTING ARE 2.5/30/500/30/5 MAGNET 30/60/500. DIAGNOSTICS WERE PERFORMED AND RESULTS WERE WITHIN NORMAL LIMITS, 2595 OHMS, IFI: NO. THE GREEN LIGHT SHOWING BATTERY CONSUMPTION WAS SHOWING HALF FULL AND THE PHYSICIAN DOES NOT THINK THIS IS CORRECT. BASED ON PT'S CURRENT SETTINGS, THE PT'S DEVICE SHOULD LAST ABOUT 4 YEARS AND HALF GREEN LIGHT MEANS THE BATTERY HAS 25% TO 50% REMAINING BATTERY LIFE WHICH IS NOT EXPECTED. X-RAYS OF THE PT'S DEVICE WERE TAKEN AND REVIEWED BY THE MFR. NO ANOMALIES WERE SEEN ON THE X-RAYS. THE PHYSICIAN RAN DIAGNOSTICS WITH PT'S HEAD TURNED DIFFERENT WAYS. WHEN THE HEAD WAS TURNED TO THE RIGHT, THE PT DID NOT FEEL PAINFUL STIMULATION, BUT WHEN THE HEAD WAS TURNED TO THE LEFT, THE PT FELT THE PAINFUL STIMULATION. DIAGNOSTICS IN ALL POSITIONS WERE OK. THE PHYSICIAN LOWERED THE SETTINGS AND THE PAIN RESOLVED. ATTEMPTS FOR FURTHER INFO HAVE BEEN UNSUCCESSFUL TO DATE.

    Description of Event or Problem · 1

    FURTHER MANUFACTURER INVESTIGATION REVEALED THAT THE ROOT CAUSE OF THE OBSERVED BATTERY VOLTAGE BEHAVIOR HAS BEEN DETERMINED TO BE THE RESULT OF EITHER AN EXTENDED DURATION OF THE REDUCED CONDUCTIVITY (I.E. HIGH BATTERY IMPEDANCE) EXPERIENCED BY CFX BATTERIES DURING THE BEGINNING OF LIFE (BOL) OR A MINUTE INTERNAL SHORT THAT MANAGED TO "BURN" ITSELF OUT RESULTING IN THE OBSERVED VOLTAGE REBOUND FOLLOWING 10% OF DISCHARGE (E.G. CONSUMPTION). NO CHANGE TO RISK HAS OCCURRED AS A RESULT OF THIS INVESTIGATION, WHICH CONTINUES TO BE "LOW." CHANGE REQUEST NUMBERS (B)(4) WERE CREATED AS A RESULT OF THIS INVESTIGATION. (B)(4) PROPOSES THAT THE DURATION OF THE 0.5V OFFSET, IMPLEMENTED BY THE FIRMWARE FOR MODEL 103/104/105/106 GENERATORS BE EXTENDED FROM 7.5% TO 15% OF CONSUMPTION WITHIN 11.X PROGRAMMING SOFTWARE IN ORDER TO MITIGATE SUCH EVENTS IN THE FUTURE. (B)(4) PROPOSES THAT THIS ISSUE BE MITIGATED EITHER THROUGH THE FIRMWARE (AS THE DEVICE IS STILL UNDER DEVELOPMENT) OR THROUGH THE PROGRAMMING SOFTWARE AS WELL.

    Description of Event or Problem · 1

    DECODER SPREADSHEET ANALYSIS WAS PERFORMED FOR THE PATIENT'S VNS PROGRAMMING HISTORY. A REVIEW OF PATIENT PROGRAMMING DATA REVEALED THAT ON (B)(6) 2011 THE INITIAL INTERROGATION OF THE DEVICE RESULTED IN A MEASURED BATTERY VOLTAGE OF 2.849V, INDICATING THAT A 25% BATTERY STATUS INDICATOR WAS DISPLAYED TO THE USER DURING THIS INTERROGATION (E.G. 25% REMAINING IS DISPLAYED AT MEASURED VOLTAGES OF 2.85V WITH DEMIPULSE GENERATORS). ALL SUBSEQUENT COMMUNICATION OPERATIONS RESULTED IN A MEASURED VOLTAGE OF 2.68V AT THE SAME PROGRAMMED SETTINGS, BASED ON CHARGE ACCUMULATION THIS WOULD HAVE RESULTED IN THE EXPECTED 100% STATUS INDICATOR. BASED ON THIS DATA, IT IS POSSIBLE THAT BATTERY ASSOCIATED WITH THIS GENERATOR MAY HAVE BEEN AN OUTLIER IN TERMS OF THE BATTERY IMPEDANCE THAT IS EXPERIENCED AT THE BEGINNING OF BATTERY LIFE. THE MANUFACTURER ADDRESSED THIS ISSUE WITH DEMIPULSE GENERATORS BY ADDING A 0.5V OFFSET TO MEASURED BATTERY VOLTAGE DURING THE FIRST 7.5% OF BATTERY CONSUMPTION TO MITIGATE THE POTENTIAL FOR ARTIFICIALLY LOW VOLTAGE MEASUREMENTS DURING THIS PERIOD. THE FACT THAT THE VOLTAGE MEASUREMENT OF 2.894V WAS RECEIVED AT 9.560% OF CONSUMPTION MAY INDICATE THAT BATTERY IMPEDANCE FOR THIS PARTICULAR GENERATOR WAS LONGER THAN MOST (E.G. AN OUTLIER). BASED ON ALL SUBSEQUENT PROGRAMMING DATA THE DEVICE APPEARS TO BE FUNCTIONING AS INTENDED.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    1 PULSE GEN MODEL 103 LYJ CYBERONICS INC 103 201513

    Patients

    Seq Age Sex Outcome Treatment
    1 48 YR