Based on the analysis of the device logfile, the case could be reconstructed.It was found that the device forced a shutdown of automatic ventilation due to a detected wrong motor position.The motor speed is being monitored continuously; speed fluctuations caused e.G.By an abraded collector disc will result in a deviation between measured and expected piston position.To prevent from damages, the system is designed to shut down automatic ventilation and to alert the user to this condition by means of a corresponding alarm.Manual ventilation and the monitoring functions remain available to the full extent.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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