Mechanical ventilation in the presence of sleep disordered breathing

An apparatus for treatment of sleep disordered breathing comprising:

• a blower for providing to a patient a supply of air at a treatment pressure in phase with the patient's respiratory breathing cycle, the respiratory breathing cycle including an expiratory phase and an inspiratory phase;
• a patient interface;
• an air delivery conduit for delivering air from the blower to the patient interface;
• a first sensor adapted to generate a first signal determined from the pressure in the patient interface;
• a second sensor adapted to generate a second signal determined from the flow of air to the patient through the patient interface;
• a synchrony module for detecting transitions between inspiration and expiration of the patient's breathing cycle from at least one of said sensors;
• and
• a controller programmed to:
• (1) receive said first and second signals and in response thereto detect the presence of first and second sleep disordered breathing events, the first event being at least one of an apnea, a hypopnea, or a snore and the second event being a different flow limitation;
• and
• (2) set a first pressure as a function of the occurrence of the first event and set a second pressure as a function of the occurrence of the second event, the first pressure being used to determine the treatment pressure provided during the expiratory phase of the breathing cycle and the second pressure being used to determine the treatment pressure provided during the inspiratory phase of the breathing cycle.

In a CPAP apparatus having (i) a blower, (ii) a patient interface, (iii) an air delivery conduit for delivering air from the blower to the patient interface, (iv) at least one sensor adapted to sense pressure or flow and to generate at least one signal from said determined pressure or flow, and (v) a controller that determines transitions between inspiration and expiration of the patient's breathing cycle, and that causes said blower to provide a supply of air to the patient interface at positive pressure in accordance with a pressure-time template, a method of controlling the blower operation comprising the steps of:

• determining the presence of a first sleep disordered breathing event from said at least one signal;
• said first sleep disordered breathing event being in the group consisting of an apnea, a hypopnea, or a snore;
• and the presence of a second sleep disordered breathing event from said at least one signal;
• said second sleep disordered breathing event being characterized by flow flattening;
• where said first and second events are determined from different characteristics of said at least one signal,
• setting a first pressure parameter of the pressure-time template for the expiration phase of the patient's breathing cycle in accordance with the first event and setting a second pressure parameter of the pressure-time template for the inspiratory phase of the patient's breathing cycle in accordance with the second event, and
• controlling the blower to deliver a supply of air at positive pressure to the patient interface in accordance with the template and in synchrony with the determined transitions between inspiration and expiration of the patient's breathing cycle.

An apparatus adapted for treatment of sleep disordered breathing comprising:

• a blower for providing to a patient a supply of air at a treatment pressure in phase with the patient's respiratory breathing cycle, the respiratory breathing cycle including an expiratory phase and an inspiratory phase;
• a patient interface,
• an air delivery conduit for delivering air from the blower to the patient interface,
• at least one sensor for sensing pressure in the patient interface or flow of air to the patient and to generate at least one signal determined from said sensed pressure or flow, and
• a controller for
• determining transitions between inspiration and expiration of the patient's breathing cycle;
• determining the presence first and second sleep disordered breathing events based on sensed pressure or flow, the first and second events being different indications of sleep disordered breathing and being based on different characteristics of said at least one signal;
• said first event being at least one of an apnea, a hypopnea, or a snore and said second event being a flow limitation, and
• setting a first pressure as a function of the occurrence of one of said events and setting a second pressure as a function of the occurrence of the other of said events, the first pressure being used to determine the treatment pressure provided during the expiratory phase of the patient's breathing cycle and the second pressure being used to determine the treatment pressure provided during the inspiratory phase of the patient's breathing cycle.