Patent ID: 8434482
Filing Date: 2013-05-07
Classification: A61M

Abstract:
1. A closed loop method of regulating piston movement of a piston and mean airway pressure (MAP) in a patient ventilator system having an exhalation valve, the method comprising the steps of: measuring a pressure at the patient and generating a measured pressure signal in response thereto; comparing a desired oscillator pressure signal to the measured pressure signal and generating a pressure output signal in response thereto; measuring piston displacement with respect to a midpoint of full stroke of said piston and generating a piston displacement signal in response thereto; subtracting the piston displacement signal from zero as a desired piston position and generating a displacement output signal in response thereto; combining the pressure output signal with the displacement output signal and generating an oscillator command signal in response thereto for regulating the piston movement; comparing a desired MAP signal to the measured pressure and generating an exhalation valve command signal in response thereto for regulating MAP at the patient; and centering said piston about said midpoint of full stroke of said piston while regulating MAP.