HeartStart MRx Monitor/Defibrillators with model numbers M3535A M3536A, M3536M, M3536MC, M3536M2, M3536M3, M3536M4, M3536M5, M3536M6, M3536M7, M3536M8, and M3536M9.

On February 26, 2020, the firm distributed Urgent Medical Device Correction letters to affected customers. Customers were informed that if the device is dropped or subjected to a severe mechanical shock, it may suffer internal damage even in the absence of visible external damage or the Ready for Use indicator unit does not immediately indicate a problem. Customers were instructed to inform all users that if the device is dropped or subjected to severe mechanical shock and the exterior case is still intact, they should immediately perform an operational check as described in the IFU section "Performing the Operational Check" in the Maintenance Chapter. The unit should be taken out of service and Philips Customer Service contacted if the unit is visibly damaged or if the device fails the operational check, i.e., if the RFU indicator changes to a red-X or the device emits a periodic audible chirp, as described in the IFU. Customers were instructed to insert a copy of the customer notice into each copy of the HeartStart MRx IFU. If you need further information or support concerning this notification, please contact your local Philips representative or call the firm at 1-800-722-9377.