131 results about "Expired gas" patented technology

A method of calculating the flux of any gas (x) in a CBC circuit for a ventilated or a spontaneous breathing subject, for example said gas(x) being; a) an anesthetic such as but limited to; i)N₂O; ii) sevoflurane; iii) isoflurane; iv) halothane; v) desflurame; or the like b) Oxygen; c) Carbon dioxide; or the like utilizing the following relationships; Flux of gas(x)=SGF (F_SX−F_EX) wherein SGF=Source of gas flow into the breathing circuit (CBC circuit) in liters/minute as read from the gas flow meter as set by the anesthesiologist; F_SX=Fractional concentration of gas X in the source gas (which is set by the anesthesiologist); F_EX=Fractional concentration of gas X in the end expired gas as determined by a portable gas analyzer, or the like.

A method and an apparatus for monitoring and controlling flows in medical equipment including an anesthetic machine and a ventilator for influencing a patient's respiratory system are disclosed. The apparatus comprises a microprocessor and an airway system comprising drive gas conduits provided with an inhalation valve (2) and an exhalation valve (5) for gas discharging as well as a ventilator end flow sensor (3) for measuring the introduced or discharged drive gas flow through the valves. The airway system also comprises patient end breathing tubing in which a patient end flow sensor (11) for measuring the patient's inspired and expired gas flow is provided. By comparing the measured values of the two flow sensors against the characteristic curve of the inhalation valve (2), the microprocessor can judge the operation states and accuracy of the respective flow sensors and the inhalation valve (2).

A versatile, multi-port, intubation-permitting oxygen mask is provided including two diaphragms (nasal and oral) each configured with a continuous, flexible, modifiable membrane from which an instrument-access port may be manually constructed, when and if needed. The novel oxygen mask preferably includes a multiple-inlet port having a standard oxygen tube connector and an interchangeable breathing-therapy device connector, a carbon dioxide sampling port, an exhaust port, and a nose clip. The mask can be worn as a standard oxygen mask during traditional oxygen therapy, yet quickly converted into an intubation mask. The clinician manually perforates the nasal and/or oral diaphragm to create a point and size of entry perfectly matched to the requirements for a variety of procedures that may be performed involving nasally or orally introduced scopes or probes—without disturbing the ongoing benefits of increased oxygen saturation and continuous monitoring of expired gases.

We describe the use of a flow directing apparatus for incorporation into a patient mask or adjacent to it and for use with a source of pressurized breathable gas such as electronically or electronically controlled fan blower or positive displacement ventilator to provide nasal or oro-nasally administered continuous positive airway pressure or bi level therapies. Such therapies are commonly used to treat sleep disordered breathing including sleep apnea and other syndromes, as well as ventilatory insufficiency. The valve apparatus includes means to direct expired air to atmosphere and inspired air from a pressure source to a user's airway. In this way advantage is provided compared to alternative means as described in the prior art which vent a user's expired gas to atmosphere through a fixed open vent.

A method and system are disclosed for assessing the capability of a first person to operate a machine, such as an aircraft or other transport vehicle. The method includes the steps of: (a) Sensing the value of at least one, and preferably two or more information parameters for assessing the fitness of the person operating the machine. The parameters include one or a combination of electroencephalogram information, electrocardiogram information, heart rate information, respiratory rate information, eye motion information, eyelid position information, eyelid motion information, expired gas mixture information, blood oxygen content information, blood oxygen saturation information and blood pressure information for the person operating the machine, and/or information about operation of the machine as well as information about actions taken by the person operating the machine. (b) Determining whether at least one value of one information parameter is/are not within the range of values deemed to be acceptable for a capable person. (c) Indicating when the at least one information parameter is/are not within the range of acceptable values, thereby indicating the person's decreased fitness and ability to operate the machine.

Methods and systems for diagnosing disorders, including, for example, disordered breathing, involve sensing one or more of a blood chemistry parameter and/or an expired gas parameter, such as expired respiratory gas concentration, blood gas concentration, and blood pH. Diagnosis of the disorder may be performed by a medical device, such as a respiratory therapy device or a cardiac therapy device, based on implantably detected blood gas/pH concentration/level or externally detected expired respiratory gas concentration. Cardiac and respiratory therapies for addressing the disorder may be adjusted based on the detected parameters.

A bymixer device and method which provides fast-response, accurate measurements of mixed inspired and/or expired gas fractions in open or closed ventilation circuits and/or in circle circuits used in anesthesia and/or critical care. The bymixer device may include a main flow channel and a bypass flow channel. The bypass flow channel includes a flow-restrictor (e.g, an orifice) that partially blocks the flow of respiratory gas through the bypass flow channel, a mixing chamber positioned upstream of the flow restrictor and a sampling apparatus (e.g., a port for withdrawing samples of gas from said mixing chamber and/or sensor(s) positioned within the mixing chamber).

A versatile, intubation-facilitating oxygen mask is provided including at least one diaphragm configured with a continuous, flexible, modifiable membrane from which an instrument-access port may be manually constructed, when and if needed. The novel oxygen mask preferably includes a multiple-inlet port having a standard oxygen tube connector and an interchangeable breathing-therapy device connector, a carbon dioxide sampling port, an exhaust port, and a nose clip. The mask can be worn as a standard oxygen mask during traditional oxygen therapy, yet quickly converted into an intubation mask. The clinician manually perforates the nasal and/or oral membranes of the one or more diaphragms to create a point and size of entry perfectly matched to the requirements for a variety of procedures that may be performed involving nasally or orally introduced scopes or probes—without disturbing the ongoing benefits of increased oxygen saturation and continuous monitoring of expired gases.

A tracheal tube ventilation apparatus to more effectively remove expired gases. In one preferred embodiment, one or more leak holes are created in the side walls of an endotracheal tube so that expired gases can leak out of the endotracheal tube above the larynx, such as into the back of the mouth (i.e., oropharynx). Each leak hole might advantageously have a diameter between 0.5 and 4.0 mm. In another preferred embodiment, a tube is attached to a proportionately larger leak hole (e.g., up to 8.0 mm) so that the expired gases can be directed away from the leak hole to a specific location, such as directed out of the mouth. In the case of mechanically controlled ventilation, a positive end expiratory pressure can be applied to this tube to mechanically assist with the process of exhaling. In each of these embodiments, it is preferred, but not required, that the endotracheal tube be an ultra-thin walled, two stage tube so as to further assist in the reduction of resistance to the flow of oxygen/air.

Method for providing ventilatory settings with regard to the airway pressure levels of an artificial ventilator, the artificial ventilator is connected to a lung, including the steps of obtaining data samples of a gas concentration of the expired gas over a single breath; selecting a plurality of data samples from the obtained data samples; calculating a tracing value being sensitive to changes of alveolar dead space on the basis of the selected data samples; repeating steps a), b) and c) for obtaining a plurality of tracing values; and changing at least one airway pressure level of the artificial ventilator, wherein from an observation of a resulting course of the plurality of calculated tracing values an airway pressure level at which alveolar opening or lung overdistension or lung open condition or alveolar closing occurs is detected. Apparatus for providing ventilatory settings with regard to the airway pressure levels of an artificial ventilator is also disclosed.

A mask interface device is provided for a protective mask of the type having a mask filter and a mask expiratory port, the mask expiratory port having an expiratory port valve of the type that is normally closed and openable upon expiration, the mask filter having an inspiratory air inlet, the mask interface device comprising: a mask interface assembly mountable to the mask and having a mounting interface for mounting an air pressure generator in fluid communication with the inspiratory inlet of the mask filter; and an expiratory port interface assembly mountable to the mask expiratory port and comprising at least one opening for venting expired gas to atmosphere and a one-way valve that is positioned to control the flow of expired gas out through the at least one opening, and wherein the one-way valve is set to an opening pressure that provides positive end expiratory pressure or PEEP. Optionally, this opening pressure is between 2.5 and 20 cm H2O. Optionally, the mask interface device interface directly with the mask filter. In one embodiment of the invention, this interface does not require the filter to have a mating connection and is therefore is universal for a broad class of filters, for example cylindrical filters that project from the mask.

The method describes a means of automatic determination of required pressure levels of a breathable gas for treating sleep apnea or other respiratory disorder such as sleep hypoventilation or chronic obstructive pulmonary disease. The method makes use of a face mask nasal prongs or similar means with venting system for elimination of expired gas to atmosphere, gas delivery tubing, and a computer controlled fan or blower or other similar source of pressurised breathable gas.

The invention relates to a pressure responsive respiratory valve apparatus for enabling positive pressure from a source of pressure to be applied to a user's airway, and allowing ingress of a breathable gas from an inlet port into a user's airway during inhalation and egress of expired tidal volume of air from the user's respiratory system to an exhalation port during exhalation. The invention minimises rebreathing of expired gas and optimizes delivery of pressurised breathable gas by venting gas only during exhalation, as well as addressing important user considerations including minimizing noise, pressure swine, and size.

A nasal interface device delivers a high flow rate of a gas having a pressure that is adjustable to a patient. The device includes a nasal insert that is adapted to deliver pressurized breathing gas to a nasal cavity of the patient, and to receive expired air. The nasal insert has a pressurized breathing gas delivery port and an expired gas port. The expired gas port has a plurality of openings extending therethrough.

A nasal interface device delivers a high flow rate of a gas having a pressure that is adjustable to a patient. The device includes a nasal insert that is adapted to deliver pressurized gas to a nasal cavity of the patient, and receive and direct expired air. The nasal insert has a pressurized breathing gas delivery port and an expired gas port. An expiratory limb pressure regulator is in fluid communication with the expired gas port.

A method and system are disclosed for assessing the capability of a first person to operate a machine, such as an aircraft or other transport vehicle. The method includes the steps of:

• • (a) Sensing the value of at least one, and preferably two or more information parameters for assessing the fitness of the person operating the machine. The parameters include one or a combination of electroencephalogram information, electrocardiogram information, heart rate information, respiratory rate information, eye motion information, eyelid position information, eyelid motion information, expired gas mixture information, blood oxygen content information, blood oxygen saturation information and blood pressure information for the person operating the machine, and/or information about operation of the machine as well as information about actions taken by the person operating the machine.
  • (b) Determining whether at least one value of one information parameter is/are not within the range of values deemed to be acceptable for a capable person.
  • (c) Indicating when the at least one information parameter is/are not within the range of acceptable values, thereby indicating the person's decreased fitness and ability to operate the machine.

The invention discloses a method and a device using the expired gas partial pressure of CO2 to monitor and estimate the CO2 partial pressure of arterial blood, belonging to the clinical respiratory monitoring technology field. The technical points includes using a CO2 analyzing and monitoring instrument for the real-time acquisition on the expiratory flow, the time and CO2 partial pressure PaCO2 to be input into a computer; processing input data; when the instant flow is 22.25 plus or minus 0.08 percent or the instant slope of the flow speed/time curve is 0.13 plus or minus 0.19, (a) and the difference of the corresponding CO2 partial pressures is within about 5 percent, the average value of the corresponding CO2 partial pressure is basically the same with the arterial blood CO2 partial pressure; (b) the corresponding CO2 partial pressure difference is over about 5 percent, the mathematical model fitting is implemented on the CO2 partial pressure/time curve to estimate the corresponding arterial blood CO2 partial pressure. The invention can be applied to clinical wound-free monitoring COPD patients, especially the PaCO2 of severe COPD patients.

The invention relates to a device for determining two or more respiratory parameters relating to an individual and a method for determining two or more respiratory parameters relating to an individual by means of the device. The disclosed device and method may be used in an individual suffering from pulmonary gas exchange problems relating to gas exchange of oxygen and/or carbon dioxide, e.g. a patient with chronic obstructive pulmonary disease. The device and method may also be used in a healthy individual or in an animal, e.g. for research experiments. The device has detection means for oxygen and carbon dioxide contents in inspired and expired gas and blood. The device is controlled by a computer with functionality for entering oxygenation, carbon dioxide and acid-base values from one or more blood samples from arterial, venous, central venous or mixed venous blood samples, and with the parameter estimation based on equations of gas exchange of both oxygen and carbon dioxide and equations describing the acid-base chemistry of blood potentially including the competitive binding of oxygen and carbon dioxide to hemoglobin.

The invention provides a detection system for expired gas. The detection system comprises an expired gas analyzer and a computer, wherein the expired gas analyzer comprises a mini vacuum pump, a gas chamber, a sensor array, a signal processing circuit and a data acquisition card; the sensor array comprises a gas sensor and an environmental monitoring sensor; the vacuum pump sucks the expired gas or clean air into the gas chamber and is in contact with the sensor array; the signal processing circuit filters responses of the sensors, and transmits the responses to the data acquisition card after amplifying the responses; and the data acquisition card transmits processed responses to the computer after digitizing the processed responses. The system can be used for assisting in analyzing expiration-related physical conditions, such as diagnosis of diabetes, blood sugar monitoring of a diabetic patient, prevention of ketoacidosis, and monitoring of fat consumption in the body building or weight losing process.

A bite block that is inserted into a patient's mouth during an endoscopic diagnostic or surgical procedure that has a channel for receiving an endoscope or other surgical instrument through the patient's mouth and additional channels transmitting a gas to the patient and transmitting expired gas from the patient.

An airway adaptor includes: an airway case; and an expired gas guiding portion which is connected to the airway case to introduce a respiratory gas to the airway case. The airway case includes: a first respiratory gas flow path in which the respiratory gas flows in a first direction; and a second respiratory gas flow path in which the respiratory gas flows in a second direction opposite to the first direction.