BEUDAMED
    FDA Adverse Event Other Summary report: N

    ACUSON

    MDR report key: 3076629 · Received April 22, 2013

    Report

    Report Number
    3009498591-2013-00002
    Event Type
    Other
    Date Received
    April 22, 2013
    Date of Event
    February 1, 2013
    Report Date
    April 17, 2013
    Manufacturer
    SIEMENS MEDICAL SOLUTIONS USA INC.
    Product Code
    ITX
    PMA / PMN Number
    072786
    Removal / Correction Number
    3009498591-04-05-2013-00
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    WA, US
    Reporter Occupation
    OTHER

    Narratives

    Additional Manufacturer Narrative · 1

    INVESTIGATION REVEALED TWO POTENTIAL MECHANISMS FOR INCREASED RESISTANCE IN THE THERMISTOR SIGNAL PATH: OXIDATION ON MPI BOARD CONTACTS BETWEEN BOARD AND TRANSDUCER PORT AND RELAYS USED TO SWITCH BETWEEN TRANSDUCER PORTS MAY INTERMITTENTLY EXHIBIT HIGH CONTACT RESISTANCE. THE ROOT CAUSE (FOR #1 ABOVE) IS A MFG DEFECT IN THE SIGNAL PATH OF THE THERMISTOR RESISTANCE MEASUREMENT CIRCUIT. THE VERSION 4 OF THE MPI BOARDS LACK THE SOLDER PILLOWS ON THE SILVER PLATED PADS IT WAS SUPPOSED TO HAVE AT THE TRANSDUCER CONTACT PINS. THEREFORE, THE PADS ARE SUSCEPTIBLE TO OXIDATION WITH TIME. OXIDATION INCREASES SIGNAL PATH RESISTANCE, WHICH RESULTS IN AN ERROR IN THE TEMPERATURE READING TOWARDS LOWER TEMPERATURES. ONCE OXIDIZED, THE RESISTANCE INCREASE IN THE SIGNAL PATH CAN BE PERMANENT OR INTERMITTENT. DURING IN-HOUSE TESTING, 2% OF THE IMAGING SIGNAL PATHS SHOWED 10 DB OR MORE SIGNAL LOSS (WHICH IS OUTSIDE THE STANDARD DEVIATION). THE SAME SIGNAL LOSS ON THE THERMISTOR SIGNAL PATH WOULD UNDERESTIMATE THE TEMPERATURE BY MORE THAN 1 DEGREE C, AND SOME OF THE MEASUREMENTS INCLUDE DATA POINTS THAT WOULD RESULT IN AN UNDERESTIMATION OF > 10 DEGREES C. SILVER TARNISH WAS FOUND ON ALL INVESTIGATED MPI4 BOARDS. CLINICAL IMPLICATIONS ARE POSSIBLE ESOPHAGEAL BURNS IN FEBRILE OR HYPERTHERMIC PTS. THE RISK OF BURN INCREASED WITH PT TEMPERATURE AND DURATION OF SCANNING.

    Description of Event or Problem · 1

    DURING INTERNAL DEVELOPMENT ACTIVITIES, IT WAS DISCOVERED THAT THE SIGNAL PATH FROM THE TRANSDUCER PORTS TO THE CIRCUITS INSIDE THE SC2000 SYSTEM MAY EXHIBIT INCREASED RESISTANCE. THE TRANSDUCER PORTS AND THE PART OF THE SIGNAL PATH THAT IS SUSCEPTIBLE TO INCREASED RESISTANCE ARE ON THE MPI BOARD. INCREASED SIGNAL PATH RESISTANCE CAN CAUSE THE FOLLOWING ISSUES ONLY IN TRANSDUCERS WHICH INCORPORATE THERMISTORS FOR THE PURPOSE OF MONITORING TRANSDUCER TEMPERATURE (V5M, V7M, AND 4Z1C TRANSDUCERS): A FAILURE OF THE HIGH TEMPERATURE WARNING (SOFTWARE) AND SHUT OFF MECHANISMS (SOFTWARE AND HARDWARE), AND AN ERROR IN THE TEMPERATURE DISPLAY. THE V5M AND V7M ARE A RISK DUE TO: TRANSDUCER UTILIZED FOR TRANS-ESOPHAGEAL IMAGING IN WHICH NEITHER THE OPERATOR OR PT WOULD RECOGNIZE AN INCREASE IN TEMPERATURE AND THESE TRANSDUCERS DO NOT CONTAIN A COOLING MECHANISM SIMILAR TO THE 4Z1C, THEREFORE, LEAVING ONLY ONE FAILURE MECHANISM OF THE MPI BOARD TO CAUSE AN ISSUE.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    171751 ACUSON DIAGNOSTIC ULTRASOUND DEVICE ITX SIEMENS MEDICAL SOLUTIONS USA INC. ACUSON SC20000

    Patients

    Seq Age Sex Outcome Treatment
    1