Abstract: An aviation or similar headset having an ear cup includes an oximeter. In one embodiment, the oximeter is mounted to a cushion of the ear cup so as to be generally coplanar thereweith. When the headset is worn, the ear cup is located about the ear of the wearer and the oximeter is positioned proximal to or against the skin of the wearer near the ear. The oximeter obtains blood-oxygen content information. The oximeter output may be provided to an oxygen delivery control apparatus arranged to control the flow of oxygen to a user in an open-loop breathing system including an oxygen supply and a delivery apparatus for delivering supplemental oxygen to a user.

Abstract: A flow probe for use in a humidification system is disclosed. The flow probe is adapted to be positioned in a humidified gases flow (for example oxygen or anaesthetic gases) such as that which is provided to a patient in a hospital environment. The flow probe is designed to provide both temperature and flow rate sensing of the gases flow by incorporating two sensors (preferably thermistors) and the shape and alignment of the probe enables accurate readings by reducing the occurrence of condensation on the sensors.

Abstract: An apparatus is provided for controlling gas delivery to a patient, to maintain effective respiratory function. The apparatus includes sensors for monitoring one or more physiological variables such as breathing airflow sound, EEG, EOG, ENG, and/or patient position. The apparatus includes a determining component for deriving, from the sensed variables, data representing a respiratory event and a component for determining from the data a gas pressure or modulated gas pressure to counteract tissue vibration associated with the respiratory event, thereby tending to cancel the respiratory event. The determining component may include an algorithm adapted to generate a gas pressure signal substantially 180 degrees out of phase relative to the tissue vibration. The apparatus may include a drug delivery module operable to deliver a drug in accordance with the sensed physiological variable and the determining component.

Abstract: A system and method of providing bi-level CPAP therapy is provided that incorporates an infrared carbon-dioxide sensor to determine whether a patient is inhaling or exhaling. Patient exhalation causes the infrared light to be absorbed, while patient inhalation reduces the presence of carbon-dioxide causes little or no absorption of carbon-dioxide. The level of carbon-dioxide in an associated patient breathing interface is monitored for thresholds that trigger higher CPAP pressure upon inhalation and lower CPAP pressure upon exhalation.

Abstract: The present invention is directed to a portable oxygen concentrator system adapted to be transported by a user. The portable oxygen concentrator system includes an energy source, an air separation device powered by the energy source and adapted to convert ambient air into concentrated oxygen gas for the user, at least one sensor adapted to sense one or more conditions indicative of the oxygen gas needs of the user, and a control unit interrelated with the air separation device and the at least one sensor to control the air separation device so as to supply an amount of oxygen gas equivalent to the oxygen gas needs of the user based at least in part upon the one or more conditions sensed by the at least one sensor.

Abstract: A piston ventilator is disclosed herein which uniquely includes an oxygen blending module which supplies oxygen enhancement for aiding patients requiring respiratory treatment. The oxygen blending module supplies a preselected enrichment of oxygen to a piston and cylinder assembly wherein the amount of oxygen permitted to flow therein is continuously monitored and controlled according to the volume above the piston in the cylinder as calculated by a controller. The oxygen blending module includes a flow sensor which monitors the flow of supplemental oxygen into the piston and cylinder assembly, and further includes a primary oxygen control valve which restricts the flow of oxygen through the flow sensor to the piston and cylinder assembly depending on the difference between the calculated desired amount of oxygen and the target amount of oxygen provided to the controller.

Abstract: A personal pure air device where an air quality visualizer that can fit in a pocket like a pen samples ambient air quality for VOC's, poisonous gases, ozone, and possibly bacterial or viral content. The invention can contain a personal air bottle containing pure compressed air which can be dispensed through a regulator and tube to a nozzle to provide a plume of pure are around the user's nose and mouth providing a space of purified personal breathing air. The visualizer can be directly connected to the regulator to automatically start a flow of pure air when ambient air quality deteriorates, or the user can simply read the air visualizer and manually start the flow of pure air when desired through the use of valves.

Abstract: A system and method for delivering fractionally inspired oxygen (FiO2) to a patient in response to receiving an arterial hemoglobin oxygen saturation signal (SpO2) are disclosed. The SpO2 is measured, for example, by using a pulse oximeter. An algorithm receives a signal indicating the SpO2. The algorithm determines wither the SpO2 is in the normoxemia range, hypoxemia range or hyperoxemia range. The algorithm also determines trends by calculating a slope of second-to-second changes in the SpO2. Based on the current SpO2 and the trend, the algorithm determines the appropriate FiO2 for the patient and instructs a device, such as a mechanical ventilator or an air oxygen mixer as to the appropriate FiO2 to be delivered to the patient. The system initializes various parameters with default values, but a user (e.g., a nurse) can also update the settings at any time.

Abstract: Methods and apparatus for enhancing reliability of, and monitoring, the operation of airway valves to enhance patient safety. Pneumatic control line pressure (positive or negative) for actuation of the airway valve may be specified at a given magnitude or within a selected range and monitored continuously. Reduced or excessive pressure may be compensated by actuation of a pressure source or a bleed valve, and monitoring may be effected so as to warn the user of any deviation from the range, or deviations of selected magnitudes or frequencies or a combination thereof. The inspired volume of CO2 may be monitored using air flow and CO2 sensing, with detection of excessive CO2 volume triggering a warning. Similarly, measured end-tidal or end-inspired CO2 or other appropriate measures of CO2 concentration may be employed as a warning trigger. Other driving energy sources for airway valves, and monitoring thereof, are also disclosed.

Abstract: The apparatus provides for the determination of the instantaneous phase in the respiratory cycle, subject's average respiration rate and the provision of ventilatory assistance. A microprocessor (16) receives an airflow signal from a pressure transducer (18) coupled to a port (17) at a mask (11). The microprocessor (16) controls a servo (19), that in turn controls the fan motor (20) and thus the pressure of air delivered by the blower (10). The blower (10) is coupled to a subject's mask (ii) by a conduit (12). The invention seeks to address the following goals: while the subject is awake and making substantial efforts the delivered assistance should be closely matched in phase with the subject's efforts; the machine should automatically adjust the degree of assistance to maintain at least a specified minimum ventilation without relying on the integrity of the subject's chemoreflexes; and it should continue to work correctly in the pesence of large leaks.

Abstract: A gas compression and delivery device for treatment of sleep disorders. The device has a motor, at least one impeller, and two air pressure chambers, each receiving air at a different pressure, one pressure applied to a patient during inspiration and one for expiration. A mask having a dual pressure gas delivery hose and a selector for letting in either the high or low pressure gas depending on the breathing cycle of the patient. The gas pressures are adjustable by means of valves on the separate chambers in the device. At least one sensor on the patient sending data to a controller in the device as to the patient's physiological data which is used to determine the patients breathing treatment needs. The controller may be a microprocessor with memory capability to store patient data for diagnosis and treatment of the patient. Telecommunications by telemetry, or telephony to a remote site allows home use of the device rather than institutional use with health care providers on site.

Abstract: Disclosed is an apparatus and method for the delivery of inspired gas, e.g., supplemental O2, to a person combined with gas sampling, including for the purpose of monitoring of the ventilation of the person. In the invention, the delivery of inspired gas and gas sampling are accomplished without the use of a sealed face mask. The apparatus of one embodiment of the present invention comprises an oxygen delivery device, nasal airway pressure sampling devices, optionally an oral airway pressure sampling device and at least one pressure analyzer connected to the sampling devices which determine the phase of the person's respiration cycle and the person's primary airway. The oxygen delivery device is connected to a controller such that it delivers a higher flow of oxygen to the person during the inhalation phase of the person's respiratory cycle. The invention thus increases end tidal oxygen concentrations.

Abstract: A pressure support system and method of using same that includes a pressure generator adapted to provide a gas flow, a conduit coupled to the pressure generator to deliver a gas flow to a patient, an interface device coupled to the conduit to communicate the gas flow to an airway of the patient. An exhaust vent that provides a flow of exhaust gas to atmosphere is provided in the conduit or the interface device. A flow sensor detects a rate at which gas flows in the conduit and provides a first output indicative thereof, and a pressure sensor detects a pressure of gas at the patient and provides a second output indicative thereof. A control system receives the first and second outputs and determines whether a current flow of exhaust gas passing through the exhaust vent is below an alarm threshold based on the first and second outputs and provides a third output indicative of this determination.

Abstract: A humidifier and humidity sensor is disclosed for use with a breathing assistance apparatus. The humidity sensor preferably includes means to sense absolute humidity, relative humidity and/or temperature at both the patient end and humidifier end. The humidifier may also include provision to both control independently the humidity and temperature of the gases. Further, a chamber manifold is disclosed to facilitate easy connection of the humidifier to various outlets, inlets and sensors. A heated conduit is described which provides a more effective temperature profile along its length.

Abstract: A medical ventilator system is disclosed which automatically controls and modifies the oxygen support provided to the patient. The system includes a source of pressurized oxygen and a fluid conduit extending between the pressurized oxygen source and a patient. A valve is fluidly connected in series with the conduit which is variably controllable to vary the oxygen support for the patient. A pulse oximeter provides an SpO2 signal representative of the blood saturation of the patient. A controller is responsive to the magnitude of the SpO2 signal as well as the rate of change of the SpO2 signal for varying the oxygen support (FiO2) to the patient by variably actuating the valve. Preferably, the controller utilizes fuzzy logic to determine the proper oxygen support for the patient.

Abstract: The present invention restores the normal low-dose flushing of the lower airways with air from the upper airways, containing nitric oxide (NO) and possible other biologically active agents by aspiration of air from the upper airways and introducing said air in the inspiratory airflow of a ventilator. The inventive apparatus and method is free from the risks associated with traditional administration of exogenous NO.

Abstract: A device is disclosed for monitoring the respiration parameters of an artificial respiration system. The proposed device has a treatment device including a filter and/or heat-and moisture exchanger fitted in a respiration tube system and is based on evaluation by a monitoring unit of pressure and/or flow-rate values in the respiration system. Inside the respiration system, pressure sensors are provided upstream and downstream of a flow resistance in the treatment device and pressure sensors are provided upstream and downstream of another flow resistance suitable as a reference. The signals from the pressure sensors are fed to the monitoring unit which determines the respiration parameters from the pressure difference &Dgr;p3 above the flow resistance in the treatment device, the pressure difference &Dgr;p4 above the other flow resistance suitable as a reference within the respiration system, and from the time t.

Abstract: A method and apparatus for a self contained underwater breathing apparatus in which a breathing gas is supplied to a flow loop from two separate gas sources each having a different oxygen fraction, and each controlled by separate mass flow controllers having variable flow rate. The mass controller flow rates are adaptively adjustable to deliver gas at variable flow rates which depend solely on a function of depth. An algorithm determines these specific flow rates from each of the tanks at particular depths, such that the gas flow from an oxygen rich gas source decreases as a function of depth, while the gas flow from a diluent gas source increases as a function of depth, so as to maintain the oxygen partial pressure in the flow loop within a specific pre-determined range.

Abstract: A safety system prevents inadvertent mixing of different anaesthetic agents, during replenishment wherein a new anaesthetic is replenished from a container to an anaesthesia machine containing a flow channel for the delivery of liquid anaesthetic, with a first anaesthetic being present downstream from the flow channel. Inadvertent mixing of different anaesthetics is avoided because the safety system has a measurement unit for identifying the new anaesthetic before the new anaesthetic comes into contact with the first anaesthetic. The measurement unit is arranged upstream from the first anaesthetic.

Abstract: A tubular respiratory assistance device which forms the wall of a main channel and is intended to be connected by its distal end to a patient's airway, so that the main channel connects the patient's respiratory system to the outside, and which has at least one auxiliary channel which is associated with deflection means for injecting a respiratory gas jet which is deflected toward the interior of the main channel and is intended to ventilate the patient. The tubular respiratory assistance device also has an annular chamber arranged at the periphery of it, coaxially with it on its distal end, and a distal annular orifice, the annular chamber communicating with the patient's respiratory system by means of the distal annular orifice and being provided with means for connection to the outside. Also, a respiratory assistance mask intended to be fitted to a patient's face which has this tubular respiratory assistance device for inlet and outlet of respiratory gas.

Abstract: In a method for determining the elastic volume (representing the gas which must be added to compensate for the compression of gas occurring in the tubing system) of a tubing system connected to a patient without the patient's lungs and airways entering into the determination, a determination of the volume of the tubing system is made at two different pressures during one breathing cycle and the elastic volume is calculated from the volumes thus determined. The volume of the tubing system can be established by adding a predetermined flow of a first gas to the tubing system, while constant pressure is maintained in the tubing system, when the flow of breathing gas to/from the patient is virtually zero, determining when the first gas starts flowing out of the tubing system and determining the volume of the added first gas, this volume constituting the volume of the tubing system.

Abstract: A method of supporting respiratory airways during ventilator-assisted respiration. The method includes applying two supplemental pressure supports. The first such supplemental pressure support includes applying pressure of a first magnitude upon initiation of and for the duration of an inspiratory phase. The second supplemental pressure support includes applying pressure of a second magnitude greater than the first magnitude of the first supplemental pressure support upon initiation of and for the duration of the expiratory phase. In this manner, full time pressure augmentation is applied to respiratory airways to thereby structurally support the airways and thus maintain in an open configuration the pathways in communication with lungs.

Abstract: Apparatus and methods for the estimation of flow and the detection of breathing (respiration) in continuous positive airway pressure (CPAP) treatment are disclosed. CPAP apparatus typically includes a flow generator for supplying air to a mask via a gas delivery tube. With changing air flow, the flow generator's speed and/or driving electrical current will alter in a manner defined by the controlling circuitry. Signals can be derived from measurements of motor speed and current, and these signals vary cyclically with patient respiration. By filtering to reject non-respiratory components, the resultant signal can be utilized to determine the instants in time at which the patient starts to inhale and exhale. The filtered signal also can be linearized using a predetermined knowledge of the pressure/flow/speed characteristics of the flow generator, and thus to derive a volumetric measure of airflow.

Abstract: A dosing device for regulating the concentration of a liquid vapor, produced by vaporizing liquid from a liquid source, in a carrier gas has on-off valve which is automatically operable by a valve controller and which is connectable to one or both of the liquid and the carrier gas. A flow meter is provided in the flow path of the liquid and generates an output signal proportional to the flow of the liquid supplied for vaporization. This signal is supplied to the controller which cooperates with the valve to automatically regulate the supply of one or both of the liquid or carrier gas dependent on the output signal.