Amplitude control circuit for HF oscillation breathing appts. - varies oscillation pressure set-point using OMV control circuit until minute volume applied to patient is at desired value

摘要

The circuit regulates the oscillatory minute volume (OMV) such that it is kept at a constant value. A breathing appts. measures the volume flow of breath from a ptient, and has a control input for the oscillation signal. The output from a volume flow sensor (13) is connected to the input of the OMV-measuring circuit (19), the output of which is fed to a control amplifier (4). The output of the control amplifier is fed to an input of a multiplier (6), whose output is connected via a switch (9) to the control input for the oscillation signal (20). The second input of the multiplier is connected to the output of a breathing pattern generator (7). ADVANTAGE - ALlows separate setting of mean airway pressure (MAP) and oscillatory minute volume (OMV), independently of parameters of patient.