A dräger service engineer examined the device in follow-up of the event and could confirm the reported shut-down of automatic ventilation upon review of the log files.The issue could be traced back to the sensor which monitors the auxiliary vacuum pressure.The auxiliary vacuum pressure is needed to actuate the valves that control the ventilation and to keep the ventilator diaphragm in place during piston movement.If this vacuum pressure cannot be built-up anymore or - like in the particular case - can't be measured, the system reacts during use with a shutdown of automatic ventilation and generation of a corresponding alarm.This is readily apparent to the user who has then to continue patient support in manual ventilation, at least until availability of a replacement device.Monitoring functions and gas dosage remain unaffected.The device is back in use after replacement of the pcb which has the pressure sensor onboard.The field failure rate is inconspicuous and accepted.
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