Start-up protocols for a device and method for administering NO is described.

A portable medical ventilator using pulse flow from an oxygen concentrator to gain higher oxygen concentration includes a positive pressure source to deliver pressurized air to the patient and a negative pressure source to trigger the oxygen concentrator. A patient circuit attached to a patient interface mask connects the ventilator to the patient. The ventilator includes a controller module that is configured to generate a signal to the negative pressure device to trigger the concentrator to initiate one or more pulses of oxygen from the oxygen concentrator. The oxygen pulses are delivered to the patient interface directly through multi-tube or a multi lumen patient circuit. The oxygen does not mix with air in the ventilator or in the patient circuit and bypasses the leaks in the patient circuit and/or patient interface.

The present invention discloses a carbon dioxide inhalation treatment device for central sleep apnea comprising a blower, a gas cylinder filled with carbon dioxide (CO.sub.2), an airbag, a mask, and a detection mechanism for detecting the central apnea by measuring the electromyographic activity of the chest wall muscles. The mask is provided with multiple holes providing a communication between the inside and outside of the mask in order to prevent any sense of resistance of breathing and to provide greater control of inspired CO.sub.2. Inspired CO.sub.2 from a gas mixture containing also a minimum 20% O.sub.2 is driven by air using a blower into a mixing chamber. This carbon dioxide inhalation treatment device for central sleep apnea can provide a stable, mild level of carbon dioxide for patients with central sleep apnea, thus by preserving respiratory drive correcting central sleep apnea without increasing the arousal and microarousal frequency.

A respiratory flow therapy apparatus including a sensor module can measure a flow rate of gases or gases concentration provided to a patient. The sensor module can be located after a blower and/or mixer. The sensor module can include at least an ultrasonic transmitter, a receiver, a temperature sensor, a pressure sensor, a humidity sensor and/or a flow rate sensor. The receivers can be immersed in the gases flow path. The receivers can cancel delays in the transmitters and improve accuracy of measurements of characteristics of the gases flow. The receivers can allow for detection of a fault condition in a blower motor of the apparatus.

In alternative embodiments, provided are mechanical ventilators and methods for making and using them.

Apparatus and methods for delivering a heated and humidified mixture of oxygen and air are provided. The apparatus includes an air compressor and oxygen concentrator enclosed in the housing of a vapor transfer system. The air compressor supplies air at a first pressure to a gas inlet. The oxygen concentrator provides oxygen at a second pressure to the gas inlet. The oxygen concentrator and the air compressor are in fluid communication and are configured such that the first pressure of the compressed air and the second pressure of the oxygen are about equal. The apparatus includes a vapor transfer system having a gas passage, a liquid passage having heated liquid and vapor, and a membrane that separates the gas passage and liquid passage. The membrane is positioned to transfer vapor from the liquid passage to the gas passage.

In one embodiment, a method for accurate leak estimation in a flow generation system includes measuring a total flow through the flow generation system, measuring a pressure in in the primary flow circuit of the flow generation system, determining when the measured pressure is within a predetermined threshold of EPAP, and calculating an intentional leak flowrate and an unintentional leak flowrate based on the relationship Q.sub.FS(t)=Q.sub.IL(t)+Q.sub.UL(t) when the measured pressure is within the predetermined threshold. In another embodiment, a flow generation system includes in one embodiment an airflow generator connected in-line to a flow sensor, a pressure sensor and a patient interface connection by a first gas flow circuit, and a controller electrically coupled to the airflow generator, the flow sensor and the pressure sensor. The controller sends a control signal to the airflow generator based on a first flow value measured from the flow sensor and an unintentional leak flow value that is derived from a proportional relationship with an intentional leak flow value.

A resuscitation bag system (1) useable for resuscitating a person in cardiac arrest, and having a gas control unit (90) with a first valve (92) fluidly connected to a first (922) and to a second conduit (923), the first (922) and second conduits (923) being arranged in parallel and further fluidly connected to the first conduit element (56), the first conduit (922) having a first flow restriction (924) configured for limiting the gas flow to a first flowrate, and the second conduit (923) comprising second flow restriction (925) configured for limiting the gas flow to a second flowrate, with the second flowrate being less than the first flowrate.

A device includes a body defining a respiration passage in fluidic communication with a filter fitting disposed on a first end of the body and a mask fitting disposed on a second end of the body, and a treatment passage in fluidic communication with the mask fitting. A treatment fitting is disposed on the body and is coupleable to a treatment source such that a seal in the treatment fitting transitions from a closed state to an open state to allow fluidic communication between the treatment source and the treatment passage. The device configured to permit (i) inhalation air and/or exhaled breath to be drawn and/or expelled through the filter fitting, the respiration passage, and the mask fitting and (ii) a respiratory therapeutic to be drawn from the treatment source coupled to the treatment fitting, through the treatment passage, and through the mask fitting.

A fluid delivery system provides fluid, such as supplement oxygen, to a patient in response to inhalation. The fluid delivery system includes a valve assembly that is triggered by sensing onset of inspiration by measuring a change in temperature of air flow in a nasal or oral cannula, mask or helmet.