DETERMINING INSTANTANEOUS ELASTIC RECOIL AND ASSISTANCE PRESSURE DURING VENTIALIATORY SUPPORT

摘要

The apparatus provides for the determination of theinstantaneous phase in the respiratory cycle, subject's average respirationrate and the provision of ventilatory assistance. A microprocessor receivesan airflow signal from a pressure transducer coupled to a port at a mask.The microprocessor controls a servo that in turn controls the fan motor andthus the pressure of air delivered by the blower. The blower is coupled to asubject's mask by a conduit. The invention seeks to address the followinggoals: while the subject is awake and making substantial efforts thedelivered assistance should be closely matched in phase with the subject'sefforts; the machine should automatically adjust the degree of assistance tomaintain at least a specified minimum ventilation without relying on theintegrity of the subject's chemoreflexes; and it should continue to workcorrectly in the presence of large leaks.