Abstract: A gas delivery system that generates a pressurized flow of breathable gas for delivery to a patient. The system includes a primary gas delivery system for delivering a flow of pressured gas to the airway of a patient and supplemental gas delivery system. The supplemental gas delivery system is in the form of a modular gas regulator assembly that regulates the flow of supplemental gas from a gas source to the primary gas delivery system so that supplemental gas is delivered to the patient concomitant with the pressurized flow of breathable gas. The system allows the user to selectively control the gas concentration level of the supplemental gas, such as oxygen, helium, nitrogen or any combination thereof, and the pressurized flow of breathable gas delivered to the patient concomitantly.

Abstract: A method and apparatus for monitoring a patient's respiratory status during the delivery of gases, such as supplemental oxygen. In one embodiment, a conduit carries a continuous flow of gas to an airway of a patient over a plurality of respiratory cycles and a gas flow characteristic of the gas in the conduit is monitored using a pressure sensor, a flow sensor, or both. The gas flow characteristic is used to determine a respiratory variable for the patient.

Abstract: An insufflation system that includes a first tube that inserts into a patient's airway for providing a primary flow of breathing gas to such a patient. At least one insufflation catheter is provided in or within the first tube for delivering a flow of insufflation gas to the patient. In one embodiment, the flow of insufflation gas is delivered in a first direction generally toward the patient's lungs and in a second direction generally opposite the first direction so that the flow in the second direction is greater than the flow in the first direction. As a result, a negative stagnation pressure is created that is sufficient to substantially cancel out the positive stagnation pressure generated by flow in the first direction in conjunction with a pressure drop induced in the first tube by the presence of the insufflation catheter.