Patent ID: 6609517
Filing Date: 2003-08-26
Classification: A61M

Abstract:
An apparatus for delivering pressurized breathing gas to an airway of a patient, comprising:a gas flow generator; a patient interface coupled to the gas flow generator to communicate a flow of breathing gas from the gas flow generator with an airway of a patient; a sensor associated with the gas flow generator or the patient interface that detects a fluid characteristic associated with the flow of breathing gas within the patient interface and outputs a signal corresponding to the fluid characteristic; a pressure controller associated with the gas flow generator or the patient interface to control a pressure of the flow of breathing gas delivered to a patient; an input device; and processing means, adapted to receive the signal output from the sensor, and an inspiratory gain and an expiratory gain from the input device, for producing a command signal, which is determined as: (1) a product of the inspiratory gain and the fluid characteristic during at least a portion of an inspiratory phase of such a patient's breathing cycle, and (2) a product of the expiratory gain and the fluid characteristic during at least a portion of an expiratory phase of such a patient's breathing cycle, and wherein the processing means provides the command signal to the pressure controller so that a pressure of the breathing gas delivered to a patient varies during at least a portion of the inspiratory phase and during at least a portion of the expiratory phase with fluctuations of the fluid characteristic.