Abstract: Apparatus and methods for determining a respiratory quotient are described. In one embodiment, a respiratory gas exchange monitor includes a respiratory gas conduit, a respiratory gas flow meter coupled to the respiratory gas conduit, and a respiratory gas sensor coupled to the respiratory gas conduit. The respiratory gas exchange monitor also includes a computation unit coupled to the respiratory gas flow meter and the respiratory gas sensor. The computation unit is configured to process outputs of the respiratory gas flow meter and the respiratory gas sensor to determine an amount of carbon dioxide produced by a subject and an amount of oxygen consumed by the subject, and the computation unit is configured to determine a respiratory quotient of the subject based on the amount of carbon dioxide produced and the amount of oxygen consumed.

Abstract: There is provided an improved system for expired gas analysis indirect analysis indirect calorimetry comprising a unique compliant mixing chamber that is directly connected to a mouthpiece that, itself, is unique in providing enhanced saliva and expired moisture trapping capability. The volume of the inspired and expired gas as well as at least the oxygen and carbon dioxide concentrations in the expired gas in the mixing chamber are determined. The metabolic rate of the subject is calculated therefrom taking into account the anatomical dead space in the body of the subject. The mixing chamber is compliant, sized to accommodate a single expiration and partially open to the environment. Preferably, the system also includes means to determine the oxygen and carbon dioxide content of the inspired gas as well.

Abstract: A method and apparatus for measuring pulmonary blood flow in a subject by pulmonary exchange of oxygen and an inert gas with the blood using a divided respiratory system. One method of isolating two or more divisions of the respiratory system uses a multi-lumen cuffed endobronchial catheter. In one embodiment, a triple-lumen cuffed endobronchial catheter is provided. In another embodiment, gas mixtures are supplied to each lumen using a bag-in-a-box type ventilator for each breathing system for synchronizing the rate and pressure of mixed gas supplied to the lumens.

Abstract: A system and method for determining an individualized drug dosage is provided. The system includes a metabolic rate sensing means for sensing the metabolic rate of the individual. The system also includes a computing device having a processor, a memory, an input device, and a display device. The system further includes a data storage means operatively in communication with the processor, and the data storage means includes a drug database containing drug dosage data. The method includes the steps of determining a standardized dosage for a drug. The method also includes the steps of measuring the actual metabolic rate of the individual and determining a metabolic comparison factor by comparing the measured actual metabolic rate to a predetermined standard metabolic rate. The method further includes the steps of adjusting the standardized drug dosage using the comparison factor.

Abstract: An indirect calorimeter for measuring the metabolic activity of a subject includes a respiratory connector operative to be supported in contact with the subject so as to pass inhaled and exhaled gases therethrough as the subject breathes, and a flow tube forming a flow pathway for passing inhaled and exhaled gases therethrough, wherein one end of the flow tube is operatively connected to the respiratory connector and the other end of the flow tube is open, and a wall of the flow tube includes an opening. The indirect calorimeter also includes a flow meter adapted to generate a signal as a function of the instantaneous volume of inhaled and exhaled gases in the flow pathway that is in fluid communication with the flow pathway via the opening in the flow tube, and an oxygen sensor operative to generate a signal as a function of the instantaneous fraction of oxygen in the inhaled and exhaled gases in the flow pathway that is in fluid communication with the flow pathway via the opening in the flow tube.

Abstract: A respiratory analyzer for a person comprises a flow path through which the person breathes; a metabolic rate meter, providing a metabolic rate for the person; a ketone sensor, providing a ketone signal related to the concentration of respiratory components correlated with a level of ketone bodies in exhalations of the person; a display; and an electronic circuit, receiving the ketone signal and the metabolic data, and providing a visual indication of the metabolic rate and the ketone signal to the person on the display. The respiratory analyzer can be used in an improved exercise management program for the person.

Abstract: An improved respiratory analyzer comprises a disposable flow module and non-disposable electronics module. An improved ventilator system comprises a supply of respiratory gases, a ventilator line for directing the respiratory gases to a patient, a flow module holder located in series with the ventilator line into which a flow module can be inserted, and an electronics module which connects to the flow module. In a preferred embodiment, the flow module and electronics module operate in combination to provide the functionality of an indirect calorimeter, so as to determine the metabolic rate of the patient. Feeding of an intubated patient can be controlled using determined patient metabolic rates. Other respiratory parameters can be determined by the system, such as peak flow, tidal volume, end-tidal concentrations, and respiratory quotient. The system provides a non-invasive method of cardiac output determination. A flow module can also be inserted into the mouth or internal respiratory tube of a person.

Abstract: An indirect calorimetry system includes transducers sensitive to expired airflow that are enclosed within a calorimeter housing, and a microprocessor in communication with the transducers for calculating expiration characteristics. A graphical display displays the expiration characteristics. A communication link transmits expiration characteristics to external devices such as a computer, communication network, or PDA.

Abstract: An indirect calorimeter for measuring the subject's oxygen consumption per unit time employs a mouthpiece through which the subject breathes for a period of time. Conduits connect the mouthpiece to a flow meter and a capnometer so that the subject's inhalations and exhalations pass through the flow meter and the exhalations also pass through the capnometer. Electrical signals from the flow meter and capnometer are provided to a computer which calculates the CO2 exhaled by the subject during the test by integrating the instantaneous CO2 content of an exhalation as measured by the capnometer over the volume as measured by the flow meter and subtracts that quantity from the exhaled volume and subtracts their difference from the inhaled volume. In alternative embodiments the system can also measure the subject's Cardiac Output and Delivered Oxygen.

Abstract: A device and method for applying positive airway pressure to a patient includes an indirect calorimetry system for measuring a patient's resting energy expenditure (REE). The device includes a breathing circuit, one end of which includes a patient interface device such as a nasal face mask. A bi-directional pump is positioned within the breathing circuit. The bi-directional pump pumps gas in a first direction during the application of positive airway pressure. The bi-directional pump reverses direction when the device is in the indirect calorimetry mode. In this IC mode, patient's expired gases are diluted and passed through an IC module containing an oxygen sensor, a carbon dioxide sensor, and a flow rate sensor. The device includes a microprocessor for calculating the patient's REE based on the measured oxygen concentration, carbon dioxide concentration, and flow rate.

Abstract: An indirect calorimeter operative to measure the respiratory oxygen consumption per unit time of a subject includes a respiratory connector operative to be supported in contact with a subject, so as to pass respiratory gases as the subject breathes into the respiratory connector, and a bi-directional flow meter having an ultrasonic flow transducer that bi-directionally transmits and receives ultrasonic signals to the transducer to generate a signal as a function of the volume of gases passing through the flow meter. The indirect calorimeter also includes a gas concentration sensor operative to generate a signal as a function of an instantaneous carbon dioxide content of gases passing by the gas concentration sensor.

Abstract: A conduit for use in establishing flow communication between a breathing apparatus, such as a mouthpiece of mask, and a metabolic analyzer, such as that used for determining the resting metabolic rate (RMR) of an individual. At least a section if the conduit may be bent or otherwise manipulated into a desired configuration and substantially retain the desired configuration until being remanipulated. Such a desired configuration may at least partially support the breathing apparatus while an individual is in a resting position. Manipulable regions of the conduit may be formed by longitudinally collapsible and expandable tubing, such as corrugated tubing, from tubing that carries elongate compliant members that may be bent and will retain a desired configuration, from viscoelastic tubing, or otherwise, as known in the art. Methods for establishing communication between an individual's airway and a metabolic analyzer are also disclosed, as are methods for effecting RMR analyses.

Abstract: A practical and improved method for evaluating the cardiopulmonary demands of work processes or tasks is disclosed. The methodology uses three different modes of analysis—measurement of ventilation, continuous heart rate monitoring, and aerobic capacity testing. An individual (2) while wearing a ventilation device (10) and a heart monitor (20) is tested for oxygen used, the work heart rate and the energy required is kilocalories for the activities measured. The data is recorded and compiled establishing the individuals response. The testing permits work to be analyzed and matches individuals capacity to perform the work in a new and cost effective way.

Abstract: An indirect calorimeter for measuring the metabolic rate of a subject includes a respiratory connector configured to be supported in contact with the subject so as to pass inhaled and exhaled gases as the subject breathes, a flow pathway, and a hygiene barrier positioned to block a predetermined pathogen from the exhaled gases. The indirect calorimeter also includes a flow pathway having a first end in fluid communication with the respiratory connector and a second end in fluid communication with a source and sink for respiratory gases. The flow pathway includes a flow tube through which the inhaled and exhaled gases pass, an outer housing surrounding the flow tube, and a chamber disposed between the flow tube and the first end.

Abstract: A method of determining a respiratory parameter for a subject using an indirect calorimeter is provided. The indirect calorimeter includes a respiratory connector for passing inhaled and exhaled gases, a flow pathway operable to receive and pass inhaled and exhaled gases having a flow tube within the flow pathway through which the inhaled and exhaled gases pass, a flow meter for determining an instantaneous flow volume of the inhaled and exhaled gases, a component gas concentration sensor for determining an instantaneous fraction of a predetermined component gas and a computation unit having a processor and a memory. The method includes the steps of initializing the indirect calorimeter and the subject breathing into the respiratory connector if the indirect calorimeter is initialized, sensing the flow volume of the inhaled and exhaled gases passing through the flow pathway using the flow meter and transmitting a signal representing the sensed flow volume to the computation unit.

Abstract: An indirect calorimeter for measuring the metabolic rate of a subject includes a disposable portion and a reusable portion. The disposable portion includes a respiratory connector configured to be supported in contact with the subject so as to pass inhaled and exhaled gases as the subject breathes. The disposable portion also includes a flow pathway operable to receive and pass inhaled and exhaled gases, having a first end in fluid communication with the respiratory connector and a second end in fluid communication with a source and sink for respiratory gases. The disposable portion is disposed within the reusable portion, which includes a flow meter, a temperature sensing means, a humidity sensing means, a pressure sensing means, a component gas concentration sensor, and a computation unit.

Abstract: A method and apparatus for measuring pulmonary blood flow in a subject by pulmonary exchange of oxygen and an inert gas with the blood using a divided respiratory system. One method of isolating two or more divisions of the respiratory system uses a multi-lumen cuffed endobronchial catheter. In one embodiment, a triple-lumen cuffed endobronchial catheter is provided. In another embodiment, gas mixtures are supplied to each lumen using a bag-in-a-box type ventilator for each breathing system for synchronizing the rate and pressure of mixed gas supplied to the lumens.

Abstract: An indirect calorimeter for measuring the metabolic rate of a subject includes a disposable portion and a reusable portion. The disposable portion includes a respiratory connector configured to be supported in contact with the subject so as to pass inhaled and exhaled gases as the subject breathes. The disposable portion also includes a flow pathway operable to receive and pass inhaled and exhaled gases, having a first end in fluid communication with the respiratory connector and a second end in fluid communication with a source and sink for respiratory gases. The disposable portion is disposed within the reusable portion, which includes a flow meter, a component gas concentration sensor, and a computation unit. The flow meter generates a signal as a function of the instantaneous flow volume of respiratory gases passing through the flow pathway and the component gas concentration sensor generates a signal as a function of the instantaneous fraction of a predetermined component gas in the exhaled gases.

Abstract: A method and apparatus for measuring changes in the concentration of a particular gas component of a breathing gas mixture after inhalation and exhalation by means of a degradable sensor. This is done by exposing, during inhalation, the sensor to a breathing gas mixture of known concentration to produce an inhalation output corresponding to the measured concentration of the gas component in the inhalation. From the known concentration of the gas component in the breathing gas mixture and the measured concentration in the inhalation output, a degradation parameter is determined representing the instantaneous degradation condition of the sensor.

Abstract: An indirect calorimeter for measuring the metabolic activity of a subject includes a respiratory connector operative to be supported in contact with the subject so as to pass inhaled and exhaled gases therethrough as the subject breathes, and a flow tube forming a flow pathway for passing inhaled and exhaled gases therethrough, wherein one end of the flow tube is operatively connected to the respiratory connector and the other end of the flow tube is open, and a wall of the flow tube includes an opening. The indirect calorimeter also includes a flow meter adapted to generate a signal as a function of the instantaneous volume of inhaled and exhaled gases in the flow pathway that is in fluid communication with the flow pathway via the opening in the flow tube, and an oxygen sensor operative to generate a signal as a function of the instantaneous fraction of oxygen in the inhaled and exhaled gases in the flow pathway that is in fluid communication with the flow pathway via the opening in the flow tube.

Abstract: An indirect calorimeter operative to measure the respiratory oxygen consumption per unit time of a subject includes a respiratory connector operative to be supported in contact with a subject, so as to pass respiratory gases as the subject breathes into the respiratory connector, and a bi-directional flow meter having an ultrasonic flow transducer that bi-directionally transmits and receives ultrasonic signals to the transducer to generate a signal as a function of the volume of gases passing through the flow meter. The indirect calorimeter also includes a gas concentration sensor operative to generate a signal as a function of an instantaneous carbon dioxide content of gases passing by the gas concentration sensor.

Abstract: A method for non-invasively determining functional cardiac output (FCO) and/or venous blood CO2 partial pressure (PvCO2). The amount of CO2 (VCO2N) released from the blood and end capillary blood CO2 content (CcCO2N) are determined from measurements from exhaled breathing gases. The CO2 content of the breathing gases inhaled by the subject is increased and values for VCO2R and CcCO2R are obtained. A regression analysis is performed using the obtained VCO2N, VO2R, CcCO2N, and CcCO2R values. The regression line is extrapolated to obtain a value for CcCO2 when (VCO2) is zero so that CvCO2 becomes known. The CvCO2 thus determined can be inserted in a non-differential form in the Fick equation, along with VCO2 and CcCO2 values from normal breathing, to determine FCO. To determine PvCO2, CvCO2 is altered in accordance with the amount of oxygen in the venous blood, to correctly indicate PvCO2.

Abstract: An improved health management system for a person is disclosed, in which the person's resting metabolic rate (RMR) is determined at intervals using an indirect calorimeter. RMR values are used in setting and revising goals in, for example, a weight control program. The effects of a weight control program on RMR can hence be compensated for, which enables an improved weight control program to be developed. In one embodiment, the person is provided with a portable electronic device, for use as a caloric intake calculator, caloric expenditure calculator, and caloric balance calculator.

Abstract: A calorimeter configured to determine a metabolic rate of an individual based on measurements of the individual's respiration. The calorimeter includes an inlet, a flow sensor, a mixing chamber, a gas sensor, and a calibrator. Each of these elements is located along a flow path through the calorimeter. The calibrator of the calorimeter includes a fan that is configured to force calibration gases, such as room air, through or past the gas sensor. A cardiac rate monitor is associated with a processor of the calorimeter. The processor is configured to substantially simultaneously determine and establish a relationship between the cardiac rate of the individual and the measured respiratory parameters or the metabolic rate of the individual. Data representative of this relationship may be communicated to a processor or memory of a portable calorimeter to be subsequently used by the individual.

Abstract: The present invention provides an indirect calorimeter for measuring the metabolic rate of a subject. The calorimeter includes a respiratory calorimeter configured to be supported in contact with the subject so as to pass inhaled and exhaled gases as the subject breathes. A flow pathway is operable to receive and pass inhaled and exhaled gases. A first end of the flow pathway is in fluid communication with the respiratory connector and a second end is in fluid communication with a source and sink for respiratory gases. A flow meter generates electrical signals as a function of the instantaneous flow volume of inhaled and exhaled gases passing through the flow pathway. A component gas concentration sensor generates electrical signals as a function of the instantaneous fraction of a predetermined component gas in the exhaled gases as the gases pass through the flow pathway.

Abstract: A metabolic fitness training apparatus is provided which measures the concentration of acetone in a trainer's breath while exercising. The metabolic fitness training apparatus include a housing, an acetone sensitive sensor, an optical detection circuit, and a mouthpiece attached to the housing. The sensor contains reagents such as salicylaldehyde or derivatives thereof which react with acetone to change the optical transparency of the sensor. The optical detection circuit may include a LED and a photodetector or a photometric instrument to measure the change in optical transparency of the sensor, and convert that change to acetone concentration. There may also be a display for viewing the acetone concentration.

Abstract: An indirect calorimeter for measuring the subject's oxygen consumption per unit time employs a mouthpiece through which the subject breathes for a period of time. Conduits connect the mouthpiece to a flow meter and a capnometer so that the subject's inhalations and exhalations pass through the flow meter and the exhalations also pass through the capnometer. Electrical signals from the flow meter and capnometer are provided to a computer which calculates the CO2 exhaled by the subject during the test by integrating the instantaneous CO2 content of an exhalation as measured by the capnometer over the volume as measured by the flow meter and subtracts that quantity from the exhaled volume and subtracts their difference from the inhaled volume.

Abstract: The present invention is a personal health management device comprising a processor executing an operating program, input means and output means. The input means receives information about an individual through various sources, including nutritional information about food ingested, biological information, and the caloric expenditure of the individual's activities. Preferably, input from the various sources occurs in real-time through wireless communications means. Input can also be obtained from internet websites and from health care providers, such as doctors. The operating program uses these inputs to output a health report using the output means, preferably on a display. The report can also be provided to health care providers. In one aspect of the invention, the output is a signal capable of operating a pharmaceutical delivery device carried on the individual. The personal health management device of the present invention provides a convenient means for a user to monitor his health.

Abstract: An indirect calorimeter for measuring the metabolic activity and related respiratory parameters of a subject includes a facial mask operative to be supported in contact with the subject so as to pass the inhalations and exhalations as the patient breathes. Both the inhaled and exhaled gasses pass through a tube which incorporates an ultrasonic pulse transit time flow meter adapted to generate electrical signals as a function of the instantaneous flow volume. A fluorescence quench oxygen sensor is supported in the flow tube and generates electrical signals as a function of the instantaneous oxygen content of the respiratory gasses. A computation unit receives output signals from the flow sensor and the oxygen sensor to calculate oxygen consumption and related parameters.

Abstract: A method and apparatus for measuring pulmonary blood flow in a subject by pulmonary exchange of oxygen and an inert gas with the blood using a divided respiratory system. One method of isolating two or more divisions of the respiratory system uses a multi-lumen cuffed endobronchial catheter. In one embodiment, a triple-lumen cuffed endobronchial catheter is provided. In another embodiment, gas mixtures are supplied to each lumen using a bag-in-a-box type ventilator for each breathing system for synchronizing the rate and pressure of mixed gas supplied to the lumens.

Abstract: In a method for the determination of an indicator which depends on respiratory data and defines the transition from the aerobic to anaerobic metabolism of a person, with the person being subjected to a physical stress, the O2 and CO2 concentration is measured directly in the respiratory gas stream of the person or in a partial stream derived there from. The time course of the concentration values or discrete concentration values are measured within at least one respiration period and the indicator defining the aerobic-to-anaerobic transition is derived from the time course of the concentration values or from discrete concentration values using a mathematical model.

Abstract: In a lung therapy method, hyperpolarized gas is administered for one breath to a subject, and a magnetic resonance scan of at least one lung of the subject is conducted. The data obtained from the scan are evaluated, specifically to determine the extent and distribution of infusion of hyperpolarized gas in the lung, as an indication of the alveolae in the lung which are open. Based on the evaluation of the data obtained in the magnetic resonance scan, a determination is made as to whether administration of a surfactant is necessary in order to improve opening of the lung. If a surfactant is administered, the procedure can be repeated to obtain an updated dataset, which can be evaluated to determine whether the administered surfactant has been effective.

Abstract: An indirect calorimeter for measuring the subject's oxygen consumption per unit time employs a mouthpiece through which the subject breathes for a period of time. Conduits connect the mouthpiece to a flow meter and a capnometer so that the subject's inhalations and exhalations pass through the flow meter and the exhalations also pass through the capnometer. Electrical signals from the flow meter and capnometer are provided to a computer which calculates the CO2 exhaled by the subject during the test by integrating the instantaneous CO2 content of an exhalation as measured by the capnometer over the volume as measured by the flow meter and subtracts that quantity from the exhaled volume and subtracts their difference from the inhaled volume. In alternative embodiments the system can also measure the subject's Cardiac Output and Delivered Oxygen.

Abstract: An improved respiratory analyzer comprises a disposable flow module and non-disposable electronics module. An improved ventilator system comprises a supply of respiratory gases, a ventilator line for directing the respiratory gases to a patient, a flow module holder located in series with the ventilator line into which a flow module can be inserted, and an electronics module which connects to the flow module. In a preferred embodiment, the flow module and electronics module operate in combination to provide the functionality of an indirect calorimeter, so as to determine the metabolic rate of the patient. Feeding of an intubated patient can be controlled using determined patient metabolic rates. Other respiratory parameters can be determined by the system, such as peak flow, tidal volume, end-tidal concentrations, and respiratory quotient. The system provides a non-invasive method of cardiac output determination. A flow module can also be inserted into the mouth or internal respiratory tube of a person.

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: A device is provided, which is capable of determining the maximum oxygen uptake quantity without the restriction of a large device or requiring troublesome operations to be carried out. The device displays the upper and lower limit values for the pulse rate corresponding to an appropriate exercise intensity, and realizes in a wireless manner by means of optical communications the sending and receiving of information such as pulse wave signals to and from an information processing device which processes pulse wave information.

Abstract: The present invention relates to a diagnostic agent for diabetes, which comprises glucose labelled with 13C at a specific position, or pyruvic acid labelled with 13C at least one specific position. According to the present invention, there is provided a diagnostic agent for diabetes which can be used safely without side effects to give accurate results immediately with less physical pains on the subject. The present diagnostic agent for diabetes can distinguish between healthy persons and patients with diabetes even under the circumstances where the patients are easily missed, and further it can determine the type of diabetes (insulin-dependent type or insulin-independent type).

Abstract: A portable system for the measurement of the metabolic parameters of an individual, athlete or patient, in real conditions of physical activity, using a “breath by breath” technique. The portable system includes a portable unit (1) that has a reduced weight and dimensions, and is fixed to the body of the individual by means of an anatomic harness (2) during the test, a turbine flowmeter (3-4-8) applied at the mouth of the individual through an anatomic face mask (6-7-8), a heart rate monitor belt (10), a rechargeable battery (11) for supplying the system, and a receiver unit (12) that is connected to a personal computer (14) by RS232 connection (13), allowing the receipt and display of the measurement in real time on the screen.

Abstract: Apparatus for exercising the muscles of the respiratory system for improving endurance. The apparatus includes a bag which is inflatable for receiving a predetermined volume of expired air. A valve is closed during rebreathing of expired air in the bag and is adapted to open in response to deflation of the bag to admit fresh air to the air way. The valve is also adapted to open when the bag is fully inflated to release excess expired air. The breathing frequency is paced so that, in combination with the predetermined volume, the overall ventilation may be maintained over a period of time for increasing endurance. As endurance is increased over time, the bag may be replaced with incrementally larger volume bags or the bag volume may be incrementally increased. Guidance of the training schedule and central monitoring of the training are also provided.

Abstract: A method of detecting cyanide concentration in the cutaneously transpired gas of a patient, allowing for the timely implementation of an appropriate treatment. Where the skin of a patient suffering from cyanide poisoning has been burnt, the present invention provides for a noninvasive means of cyanide treatment. In practice, a material is impregnated with methemoglobin and attached to a patient's skin. A barrier means located between the impregnated material and the patient's skin allows for the transfer of cyanide gas from the patient into the material. However, this barrier means does not allow for the transfer of the methemoglobin from the impregnated material into the patient's skin. The material is monitored for photometric change, and, where a change indicative of cyanide poinsoning is present, appropriate treatment is administered.

Abstract: A method of calculating the carbon dioxide elimination of a patient that includes counteracting any inaccuracy or inconsistency in respiratory flow measurements that may be caused by "noise", such as is attributable to respiratory circuit leaks, signal drift, a non-unity respiratory quotient, or another respiratory flow error-inducing factor. The method includes monitoring the respiratory flow and carbon dioxide of the patient during at least a portion of both inspiration and expiration; calculating an inspiratory tidal volume, an inspiratory volume averaged carbon dioxide fraction, an expiratory tidal volume, and an expiratory volume averaged carbon dioxide fraction; and selecting a tidal volume to replace at least one of the inspiratory tidal volume and the expiratory tidal volume. The carbon dioxide elimination of the patient is then calculated with the select tidal volume, the inspiratory volume averaged carbon dioxide fraction, and the expiratory volume averaged carbon dioxide fraction.

Abstract: A device and method for measuring critical portions of an individual's forced expiratory efforts. The device includes a series of preset negative pressure sensors attached to a sensor port located in a breathing tube of predetermined dimension. A patient blows through the breathing tube triggering the various sensors depending on the airflow rate. The time each of the sensors are activated is recorded. The recorded information can be used to determine various diagnostic parameters.

Abstract: A device for determining the level of nitric oxide in an exhaled airstream belonging to a living organism selected to have its lung function evaluated, where an initial device is arranged to determine the current portion of nitric oxide and/or the distribution of nitric oxide over time during an exhalation phase. During the commencing period of the exhalation phase, the exhaled air is arranged to pass with no or with only a very small resistance or back-pressure to a free space, and during the remaining period, the exhaled air is arranged to pass through the initial device against the action of a suitable resistance or back-pressure. The level of nitric oxide is measured during this remaining period.

Abstract: A patient monitoring apparatus for monitoring and/or measuring a physiological characteristic of said patient. A user interface having an interior portion communicates with an airway of a user such that substantially all gas inhaled and exhaled by the user enters the interior portion of the user interface. At least one vent element is associated with the user interface and communicates the interior portion of the user interface with an ambient atmosphere outside the user interface. The vent element and user interface define a flow element across which a pressure differential is created during inhalation and exhalation. The pressure differential is the pressure difference between the pressure within the interior portion of the user interface and the pressure of the ambient atmosphere outside the user interface.

Abstract: A method of detecting and quantifying cyanide concentration in a patient, by monitoring photometric changes resulting from the transformation of methemoglobin to cyanomethemoglobin. The present invention provides for a means of cyanide poisoning assessment in patients using the affinity of methemoglobin for cyanide to assess the photometric changes resulting from methemoglobin converting to cyanomethemoglobin, as an indicator of cyanide concentration in a patient. Appropriate corrective action can then be promptly taken.

Abstract: A non-invasive method for the functional assessment of an inherited metabolic disorder in infants and children including administering to the patient a predetermined substrate labeled with a stable non-radioactive isotope of carbon .sup.13 C, analyzing the breath samples for the isotopic abundance of .sup.13 CO.sub.2, and calculating the quantity of substrate oxidized for determining the rate of substrate oxidation.

Abstract: A device for dynamic recording of respiratory, metabolic and/or ventilatory quantities during a process or influence conducive to lactate production, having a data processing facility (18) incorporating a display unit and also a computing unit, and having a device (20) connected via an analysis instrument (22) to said data processing facility for determination of respiratory minute volume and also of O.sub.2 content of CO.sub.2 content of said respiratory minute volume of inhaled or exhaled air, wherein with said computer unit using the respiratory measuring quantities of respiratory minute volume V.sub.e of the O.sub.2 content of the respiratory minute volume V.sub.o2 and of the CO.sub.2 content of the respiratory minute volume V.sub.co2 according to an algorithm, to permit determination of a quantity x as a function of the work performed per unit of time (P).

Abstract: The present invention relates to a diagnostic agent for diabetes, which comprises glucose labelled with 13C at a specific position, or pyruvic acid labelled with 13C at least one specific position. According to the present invention, there is provided a diagnostic agent for diabetes which can be used safely without side effects to give accurate results immediately with less physical pains on the subject. The present diagnostic agent for diabetes can distinguish between healthy persons and patients with diabetes even under the circumstances where the patients are easily missed, and further it can determine the type of diabetes (insulin-dependent type or insulin-independent type).