Unfortunately, the log file was not provided by the biomedical technician.However, the logfile reportedly logged entries regarding ¿motor slow¿, ¿motor stall¿ and ¿motor fail¿.In combination with the described symptom, the entries demonstrate that the supervisor function of the software forced a shutdown of automatic ventilation after having detected a stalled motor.This is a safety measure to prevent from mechanical damages to the ventilator unit.The user is alerted to the shutdown of automatic ventilation by a corresponding alarm; manual ventilation remains possible and the other device functions, like gas dosage and monitoring, remain unaffected.The device was in operation for approx.13 years now; it is seen likely that beginning wear and tear at the collector disc of the ventilator motor has led to intermittent losses of electrical contact between collector and the carbon brushes which resulted in speed fluctuations and finally to a stalling of the motor.Therefore, it was recommended to exchange the motor unit.Dräger finally concludes that the device behaved as specified upon the malfunction of a single component; no patient consequences have been reported.The number of similar cases, related to the same root cause, is within the expected range of the respective risk assessment and thus accepted.
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