US20040199083A1 - Metabolic calorimeter employing respiratory gas analysis - Google Patents

Metabolic calorimeter employing respiratory gas analysis Download PDF

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US20040199083A1
US20040199083A1 US10712760 US71276003A US2004199083A1 US 20040199083 A1 US20040199083 A1 US 20040199083A1 US 10712760 US10712760 US 10712760 US 71276003 A US71276003 A US 71276003A US 2004199083 A1 US2004199083 A1 US 2004199083A1
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flow
oxygen
gases
tube
exhaled
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US10712760
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James Mault
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Microlife Corp
Cooley Godward LLP
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Cooley Godward LLP
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/08Detecting, measuring or recording devices for evaluating the respiratory organs
    • A61B5/083Measuring rate of metabolism by using breath test, e.g. measuring rate of oxygen consumption
    • A61B5/0833Measuring rate of oxygen consumption

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. The indirect calorimeter further includes a processor for receiving the signals from the flow sensor and the oxygen sensor and using the signals to determine the oxygen consumption of the subject over a period of time.

Description

    RELATED APPLICATIONS
  • [0001]
    This application is a continuation of U.S. patent application Ser. No. 09/601,589 filed Aug. 4, 2000, which claims priority of U.S. Provisional Application Serial No. 60/073,812, filed Feb. 5, 1998; and 60/104,983, filed Oct. 20, 1998.
  • FIELD OF THE INVENTION
  • [0002]
    This invention relates to a respiratory instrument for measuring metabolism and in particular to a metabolic calorimeter for relating respiratory parameters by indirect calorimetry.
  • BACKGROUND OF THE INVENTION
  • [0003]
    U.S. Pat. Nos. 5,038,792; 5,178,155; 5,179,958; and 5,836,300, all to the same inventor as the present application, disclose systems for measuring metabolism and related respiratory parameters through indirect calorimetry. These instruments employ bidirectional flow meters which pass both the inhalations and the exhalations of a user breathing through the instrument and integrate the resulting instantaneous flow signals to determine total full flow volumes. The concentration of carbon dioxide generated by the user is determined by either passing the exhaled volume through a carbon dioxide scrubber before it passes through the flow meter, so that the differences between the inhaled and exhaled volumes is essentially a measurement of the carbon dioxide contributed by the lungs, or by the measurement of the instantaneous carbon dioxide content of the exhaled volume with a capnometer and integrating that signal with the exhaled flow volume. The oxygen consumption can then be calculated.
  • [0004]
    The scrubber used with certain of these systems was relatively bulky and required replenishment after extended usage. The capnometers used with the instruments to measure carbon dioxide concentration had to be highly precise and accordingly expensive because any error in measurement of the carbon dioxide content of the exhalation produces a substantially higher error in the resulting determination of the oxygen contents of the exhalation. Thus, there is a need in the art for an indirect calorimeter for measuring the metabolic activity and related respiratory parameters of a user.
  • SUMMARY OF THE INVENTION
  • [0005]
    The present invention is an indirect calorimeter for measuring the metabolic activity of a subject. The indirect calorimeter 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. The indirect calorimeter further includes a processor for receiving the signals from the flow sensor and the oxygen sensor and using the signals to determine the oxygen consumption of the subject over a period of time.
  • [0006]
    The present invention overcomes the disadvantages associated with prior art indirect calorimeters by providing a respiratory calorimeter in which both the inhaled and exhaled flow volumes pass through a flow meter which provides an output representative of the instantaneous flow rate and the inhalations and exhalations also pass over an oxygen sensor providing an output as a function of the instantaneous oxygen concentration in the flowing gas. These two signals are provided to a computer which integrates them to derive signals representative of the inhaled and exhaled oxygen volume. From these measurements the oxygen consumption, respiratory quotient and related respiratory parameters are calculated and displayed.
  • [0007]
    One advantage of the present invention is that the indirect calorimeter utilizes an ultrasonic transit time flow meter and a fluorescence quench oxygen sensor. Both of these sensors operate upon the respiratory gasses as they pass through a flow tube with a substantially continuous, uninterrupted internal diameter so that the flow is substantially laminar. Previous indirect calorimeters, including those disclosed in the above-described U.S. patents, have employed flow measurement techniques that require protrusions in the flow path such as pressure differential transducers, hot wire transducers or the like. Great difficulties are encountered in maintaining a largely laminar flow in transducers of this type, resulting in inaccuracies in the flow measurement. The present invention preferably employs a volume flow meter which transmits ultrasonic pulses through the flow stream in a direction either parallel to the flow path or at least having a component parallel to the flow path The transit time of the pulses is a function of the flow rate of the gas and because the interior diameter of the flow tube wall is substantially uninterrupted, laminar flow conditions are maintained providing a high uniformity of measurement.
  • [0008]
    Another advantage of the present invention is that an indirect calorimeter is provided that directly measures the oxygen concentration in the inhaled and exhaled gasses passing through the flow tube by a technique which does not introduce any protuberances into the flow area and which may be positioned to measure the oxygen content in the same area in which flow is measured. Thus, unlike previous systems which require some linear separation between the point of flow measurement and the point of gas analysis, and accordingly would result in inaccuracies were the two to be integrated, the present system does not create any phase lag between the oxygen measurement and the flow measurement which would otherwise result in inaccuracies and the need for signal processing to correct for the displacement of the measurements. The preferred embodiment of the invention employs a fluorescence quench technique for oxygen measurement which utilizes a fluoresceable chemical disposed on the interior diameter of the flow wall in the area of ultrasonic pulse transmission. This fluorescent coating may be formed on the tube wall directly or supported on the end of a fiber optic probe terminating in alignment with the interior diameter of the tube. This coating is subjected to exciting radiation from the exterior of the tube and the resulting fluorescence may be measured from the exterior. The fluorescence is quenched by oxygen passing over the coating and the percentage of oxygen in the flow tube can be instantaneously measured by the intensity of the fluorescence.
  • [0009]
    Still another advantage of the present invention is that the flow tube is preferably formed as a disposable insert which may be inserted into a permanent, reusable structure which includes the ultrasonic transmitter and receiver and the fluorescence oxygen sensor. The fluorescent coating may be covered on the tube side with a microbial filter formed as part of the disposable insert. This filter prevents the fluorescent coating from being bacterially contaminated. The disposable insert is utilized to avoid the spread of disease from user to user in situations in which the indirect calorimeter is used by a succession of persons. The insert is preferably produced of an inexpensive material such as plastic.
  • [0010]
    A further advantage of the present invention is that the disposable insert is supported by a disposable breathing mask that covers the nose and the mouth of the user, allowing normal breathing over the measurement time. Most prior art devices have employed mouthpieces; however, it has been determined that in many users the mouthpiece can induce a mild form of hyperventilation which increases the user's energy consumption and results in erroneous metabolic readings. In one embodiment of the present invention, the metabolic measurement components are integrated with and are contained within the mask with no requirement for external connections. When the mask is attached to the user's head by straps, adhesive, or the like, it allows a full range of user movement during the measurement. Thus, it can be used during normal exercise to allow determination of the effect of that activity on respiratory parameters and may also be used to measure resting energy expenditure. The increased user comfort resulting from the elimination of connections between the mask and associated apparatus allows measurements to be made over longer periods of time and minimizes the labored breathing often associated with conventional respiratory masks which affects accurate measurement of energy expenditure.
  • [0011]
    Still a further advantage of the present invention is that the mask preferably incorporates a nasal spreader on its interior surface which adhesively attaches to the nares of the user's nose and pulls them outwardly to enlarge the nose flow area and minimize the energy expenditure in breathing, which is often increased with conventional masks.
  • [0012]
    Yet still a further advantage of the present invention is that the computation unit and display and controls are supported in a separate desktop unit and connected to the sensors within the mask by highly flexible cables.
  • [0013]
    Other features and advantages of the present invention will be readily appreciated, as the same becomes better understood after reading the subsequent description taken in conjunction with the accompanying drawings.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0014]
    [0014]FIG. 1 is a perspective view in exploded form of a first embodiment of the invention;
  • [0015]
    [0015]FIG. 2 is a cross-sectional view through the flow tube of FIG. 1; and
  • [0016]
    [0016]FIG. 3 is a perspective view of a second embodiment employing a desktop computation and display unit
  • DETAILED DESCRIPTION OF THE INVENTION
  • [0017]
    Referring to FIGS. 1 and 2, a preferred embodiment of the invention includes a disposable section, generally indicated at 10, and a nondisposable section shown exploded into parts generally indicated at 12 a and 12 b. The disposable section 10 is made of low cost materials and is intended to be replaced when the calorimeter is employed by serial users to avoid hygiene problems such as transfer of bacterial infections. The disposable section 10 may be retained by a user for reuse at a later date or may be discarded. If the calorimeter is repeatedly used by a single user, the section 10 need not be discarded between uses. The section 10 broadly consists of a mask 14 and a U-shaped breathing tube generally indicated at 16. The mask is adapted to be retained over a user's face so as to cover the user's nose and mouth. The mask 14 has a resilient edge section 18 which engages the user's face in an airtight manner. The mask may be supported against the user's face by the user holding the outer side, but preferably the mask has straps 20 which connect to its edges and pass around the rear of the user's head. Alternatively, the mask could be retained by a pressure sensitive coating formed on the edge seal 18.
  • [0018]
    The mask proper is preferably formed of a rigid plastic but the section 22 at the top of the mask which is intended to surround the user's nose, is preferably formed of a more resilient material. Pressure sensitive adhesive pads 24 are formed on the interior surfaces of the nose section 22 and allow the user to press the outer surfaces of the nose section together so as to engage the outer surfaces of the user's nares with the pressure sensitive pads 24. When the pressure on the outer surface of the nose section 22 is released, the sections will spring outwardly and will pull the nares away from the nose so as to enable easy breathing through the nose into the mask.
  • [0019]
    The U-shaped breathing tube 16 connects to the interior of the mask 14. The tube then extends from the lower forward section of the mask and extends laterally as at 26 to the right of the user in a generally horizontal plane. At the extreme right it forms a 180 degree bight 28 and extends to the left of the user in an elongated measurement section 30. The far end of the tube 16 is opened at 32 so that as the user inhales while wearing the mask 14 air is drawn into the tube 16 through the end 32 and as the user exhales air is expelled through the end 32. The straight section 30 of the tube has three windows or openings, one, 34, formed at its lower side adjacent to the bight 28, the second, 36, formed on its upper side adjacent to the opening 32 and a third, 38, formed on the side of the tube in the middle of the section 30.
  • [0020]
    The nondisposable portion of the calorimeter consists of the interlocking upper section 12 a and lower section 12 b. The upper section 12 a is formed about a semi-cylindrical section of tube 40. The inner diameter 42 of the tube section 40 matches the outer diameter of the disposable tube section 30 and the section. 40 is slightly shorter than the straight line tube section 30. Similarly, the nondisposable section 12 b is formed of a semi-cylindrical tube half 44 having an inner diameter matching the outer diameter of the tube section 30 and having a slightly shorter length.
  • [0021]
    The tube section 40 is formed with two rearward facing tubular supports 46 and 48, spaced along its length. These supports removably engage bosses 50 and 52 which are formed integrally with the face mask 14 and project forwardly from its upper sides. The lower tube section 44 is then locked to the upper tube section 40 so as to surround the breathing tube section 30. Cam sections 54 and 56 formed at the forward end of the tube section 40 engage latches 58 and 60 formed on the lower tube half and a similar cam (not shown) projecting from the rear of the tube 40 engages a latch 62 formed at the rear of the lower tube section 44 adjacent its free edge.
  • [0022]
    The nondisposable section also includes a flow meter. One example of a flow meter is a bi-directional flow meter. Another example of a flow meter is an ultrasonic transducer, such as the ultrasonic transceiver shown at 64. Preferably, the ultrasonic transducer is strategically placed to bi-directionally transmit and receive ultrasonic signals. Still another example of an ultrasonic flow meter is manufactured by NDD Medizintechnik AG, of Zurich, Switzerland, and disclosed in U.S. Pat. Nos. 3,738,169; 4,425,805; 5,419,326; and 5,645,071.
  • [0023]
    In this example, the ultrasonic transceiver 64 is housed in a ring 66 formed in the lower tube section 44, and projects into the window 34 of the tube section 30. An anti-microbial filter 68 covers the surface of the transducer 64. Similarly, an ultrasonic transducer, such as an ultrasonic receiver as shown at 70, is supported within a section 72 formed on the upper tube 40, and protected by a cover 74. The ultrasonic receiver 70 projects into the window 36 adjacent the outlet and inlet end of the tube 30. An anti-microbial filter (not shown) may protect the surface of the transducer. The lower tubing section 44 is integrally formed with a housing 76 which contains the microprocessor which receives the signals from the transducers and sensors and controls their operation, and computes the oxygen consumption and other respiratory factors measured by the device. The unit 76 includes a display 78 and control switches 80. In certain embodiments of the invention a digital keypad may be included on the unit 76.
  • [0024]
    The computation unit determines oxygen consumption by solving the equation VO2=V1×(F1O2)−VE×(FEO2) where VO2 is the consumed oxygen, V1 is the inhaled volume, VE is the exhaled volume, F1O2 is the fraction of oxygen in the inhalation, and FEO2 is the fraction of volume in the exhalation. The system integrates the instantaneous flow volumes with the instantaneous oxygen levels over an entire breathing cycle, which is typically four to five minutes. Other respiratory parameters such as RQ, REE, etc. may be calculated in the manner disclosed in my previous issued patents.
  • [0025]
    An oxygen concentration sensor 82 is supported within the housing 76 so that when the tube sections 40 and 44 are joined, the surface of the oxygen sensor, preferably covered with an anti-microbial filter 83, is disposed within the window 38 so that its outer surface is substantially flush with the internal diameter of the tube section 30.
  • [0026]
    The oxygen concentration sensor 82 is preferably of the fluorescent quench type as disclosed in U.S. Pat. Nos. 3,725,658; 5,517,313 and 5,632,958. One example of such a sensor is a sensor manufactured by Sensors for Medicine and Science, Inc. of Germantown, Md. The computation unit includes a source (not shown) for directing exciting radiation to the fluorescent coating on the end of the oxygen sensor 82 from exterior of the tube 30 and sensing the resulting fluorescence intensity which is diminished as a function of the concentration of oxygen and gas flowing over its surface to produce a direct measurement of oxygen concentration. The exciting radiation and fluorescent signal may be carried to the sensor by an optical fiber (not shown).
  • [0027]
    In use, a subject dons the mask 14 and attaches the straps so that the subject's nose is disposed within the section 22 of the mask, the subject's mouth is covered, and the area surrounding the mouth and nose are sealed by contact of the section 18 with the subject's face. The subject then pinches the outer surface of the section 22 of the mask so that the adhesive pads 24 are brought into pressured contact with the two sides of the subject's nose. The resilient section 22 is released so that the nares are separated, allowing free breathing within the mask.
  • [0028]
    Either prior to donning the mask or subsequently, the nondisposable sections 12 a and 12 b are attached so as to surround the tube 30 and the connecting sections 46 and 48 are attached to the bosses 50 and 52 on the front surface of the mask 14.
  • [0029]
    The user may then breathe in a normal manner so that the inhalations and exhalations are passed through the tube 16 and connect to the atmosphere at the tube end 32. After the subject has breathed through the mask for a minute or two to stabilize the breathing, one of the buttons 80 is depressed to start the measuring cycle. In alternative embodiments of the invention, rather than manually depressing the button 80 to start the measuring cycle, the computation unit 76 could sense the flow of gasses through the tube 30 and automatically initiate the measurement cycle when the breathing reached a normal level.
  • [0030]
    Preferably, the ultrasonic transducers 64 and 70 face each other and transmit and receive ultrasonic pulses along a path 90 illustrated in FIG. 2 or some alternative path which is either parallel to or has a substantial component in the direction of the flow. The gas flow acts to advance or retard the flow of the pulses so that the full transmit time of the pulses is a function of the flow rate.
  • [0031]
    In practice, after a user's breathing has stabilized and a test cycle is initiated either automatically or through manual depressions of one of the buttons 80, the flow rate and oxygen levels through the tube 30 are monitored by the sensors and provided to the computation unit. At the end of the cycle, which is preferably automatically timed, the measured quantity such as oxygen consumption will be shown on the display 78.
  • [0032]
    [0032]FIG. 3 illustrates an alternative embodiment of the invention in which the computation and display unit, 76, instead of being incorporated integrally with the nondisposable section which is secured to the master in use, is formed in a separate desktop unit 94. The unit incorporates a display 96, control switches 98, and a keyboard 100. It is connected to the section 12 a by a flexible electrical cable 102. This arrangement lowers the weight of the unit which must be supported on the mask 14 during testing and allows more convenient user control of the unit and observation of the display. The computation and control unit 76 of the first embodiment is replaced in the embodiment by a box 104 which includes a connector for the cable 102 and also supports the oxygen sensor 82 in the same manner as the embodiment illustrated in FIG. 1. Otherwise, the system of FIG. 3 is identical to the system of FIG. 1 and similar numerals are used for similar sections.
  • [0033]
    The present invention has been described in an illustrative manner. It is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation.
  • [0034]
    Many modifications and variations of the present invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the present invention may be practiced other than as specifically described.

Claims (32)

    Claims 1-47 (cancelled)
  1. 48. An indirect calorimeter, comprising:
    a flow tube configured to pass inhaled gases and exhaled gases of a subject;
    a flow meter coupled to said flow tube, said flow meter being configured to generate an output associated with a volume of said inhaled gases and a volume of said exhaled gases;
    an oxygen sensor coupled to said flow tube, said oxygen sensor being configured to generate an output associated with a concentration of oxygen in said exhaled gases; and
    a computation unit coupled to said flow meter and said oxygen sensor, said computation unit being configured to process said output of said flow meter and said output of said oxygen sensor to determine an amount of oxygen consumed by said subject.
  2. 49. The indirect calorimeter of claim 48, wherein said flow meter is an ultrasonic flow meter.
  3. 50. The indirect calorimeter of claim 48, wherein said oxygen sensor is a fluorescence quench oxygen sensor.
  4. 51. The indirect calorimeter of claim 48, wherein said output of said oxygen sensor is further associated with a concentration of oxygen in said inhaled gases.
  5. 52. The indirect calorimeter of claim 48, wherein said computation unit is configured to process said output of said flow meter to determine said volume of said inhaled gases and said volume of said exhaled gases, and said computation unit is configured to process said output of said oxygen sensor to determine said concentration of oxygen in said exhaled gases.
  6. 53. The indirect calorimeter of claim 52, wherein said computation unit is configured to determine said amount of oxygen consumed based on said volume of said inhaled gases, said volume of said exhaled gases, said concentration of oxygen in said exhaled gases, and a concentration of oxygen in said inhaled gases.
  7. 54. The indirect calorimeter of claim 52, wherein said computation unit is configured to determine an amount of carbon dioxide produced by said subject based on said volume of said inhaled gases, said volume of said exhaled gases, said concentration of oxygen in said exhaled gases, and a concentration of oxygen in said inhaled gases.
  8. 55. The indirect calorimeter of claim 48, further comprising:
    a respiratory connector coupled to said flow tube, said respiratory connector being configured to be supported in contact with said subject so as to pass said inhaled gases and said exhaled gases.
  9. 56. The indirect calorimeter of claim. 55, wherein said respiratory connector is a mask having an edge configured to form a seal with a portion of said subject's face.
  10. 57. The indirect calorimeter of claim 48, further comprising a display unit coupled to said computation unit, said display unit being configured to provide indicia of said amount of oxygen consumed.
  11. 58. An indirect calorimeter, comprising:
    a flow tube configured to pass respiratory gases;
    a flow meter coupled to said flow tube, said flow meter being configured to generate a first signal associated with said respiratory gases passing through said flow tube;
    an oxygen sensor coupled to said flow tube, said oxygen sensor being configured to generate a second signal associated with said respiratory gases passing through said flow tube; and
    a computation unit coupled to said flow meter and said oxygen sensor, said computation unit being configured to process said first signal and said second signal to determine a volume of said respiratory gases passing through said flow tube and a concentration of oxygen in said respiratory gases passing through said flow tube, said computation unit being configured to determine a respiratory parameter based on said volume of said respiratory gases passing through said flow tube and said concentration of oxygen in said respiratory gases passing through said flow tube.
  12. 59. The indirect calorimeter of claim 58, wherein said flow meter is an ultrasonic flow meter.
  13. 60. The indirect calorimeter of claim 58, wherein said oxygen sensor is a fluorescence quench oxygen sensor.
  14. 61. The indirect calorimeter of claim 58, wherein said computation unit is configured to determine oxygen consumption based on said volume of said respiratory gases passing through said flow tube and said concentration of oxygen in said respiratory gases passing through said flow tube.
  15. 62. The indirect calorimeter of claim 58, wherein said computation unit is configured to determine carbon dioxide production based on said volume of said respiratory gases passing through said flow tube and said concentration of oxygen in said respiratory gases passing through said flow tube.
  16. 63. The indirect calorimeter of claim 58, wherein said computation unit is configured to determine a respiratory quotient based on said volume of said respiratory gases passing through said flow tube and said concentration of oxygen in said respiratory gases passing through said flow tube.
  17. 64. An indirect calorimeter, comprising:
    a first sensor configured to generate an output associated with inhaled gases and exhaled gases of a subject;
    a second sensor configured to generate an output associated with said exhaled gases; and
    a computation unit coupled to said first sensor and said second sensor, said computation unit being configured to process said output of said first sensor to determine a volume of said inhaled gases and a volume of said exhaled gases, said computation unit being configured to process said output of said second sensor to determine a concentration of oxygen in said exhaled gases, said computation unit being configured to determine an amount of carbon dioxide produced by said subject based on said volume of said inhaled gases, said volume of said exhaled gases, and said concentration of oxygen in said exhaled gases.
  18. 65. The indirect calorimeter of claim 64, wherein said first sensor is a flow meter.
  19. 66. The indirect calorimeter of claim 65, wherein said flow meter includes a plurality of ultrasonic transducers.
  20. 67. The indirect calorimeter of claim 64, wherein said second sensor is an oxygen sensor.
  21. 68. The indirect calorimeter of claim 67, wherein said oxygen sensor is a fluorescence quench oxygen sensor.
  22. 69. The indirect calorimeter of claim 64, wherein said computation unit is configured to determine an amount of oxygen consumed by said subject based on said volume of said inhaled gases, said volume of said exhaled gases, and said concentration of oxygen in said exhaled gases.
  23. 70. The indirect calorimeter of claim 64, wherein said computation unit is configured to determine a respiratory quotient of said subject based on said volume of said inhaled gases, said volume of said exhaled gases, and said concentration of oxygen in said exhaled gases.
  24. 71. The indirect calorimeter of claim 64, further comprising:
    a flow tube configured to pass said inhaled gases and said exhaled gases as said subject breathes, said first sensor and said second sensor being coupled to said flow tube.
  25. 72. An indirect calorimeter, comprising:
    means for determining a volume of inhaled gases of a subject and a volume of exhaled gases of said subject;
    means for determining a concentration of oxygen in said exhaled gases; and
    means for determining an amount of carbon dioxide produced by said subject based on said volume of said inhaled gases, said volume of said exhaled gases, and said concentration of oxygen in said exhaled gases.
  26. 73. The indirect calorimeter of claim 72, further comprising:
    means for determining an amount of oxygen consumed by said subject based on said volume of said inhaled gases, said volume of said exhaled gases, and said concentration of oxygen in said exhaled gases.
  27. 74. The indirect calorimeter of claim 72, further comprising:
    means for determining a respiratory quotient of said subject based on said volume of said inhaled gases, said volume of said exhaled gases, and said concentration of oxygen in said exhaled gases.
  28. 75. A method for respiratory gas analysis, comprising:
    determining a volume of respiratory gases of a subject;
    determining a concentration of oxygen in said respiratory gases; and
    determining an amount of carbon dioxide produced by said subject based on said volume of said respiratory gases and said concentration of oxygen in said respiratory gases.
  29. 76. The method of claim 75, wherein determining said volume of said respiratory gases includes determining a volume of inhaled gases of said subject and a volume of exhaled gases of said subject.
  30. 77. The method of claim 76, wherein determining said concentration of oxygen in said respiratory gases includes determining a concentration of oxygen in said exhaled gases.
  31. 78. The method of claim 77, wherein determining said amount of carbon dioxide produced includes determining said amount of carbon dioxide produced based on said volume of said inhaled gases, said volume of said exhaled gases, and said concentration of oxygen in said exhaled gases.
  32. 79. The method of claim 75, further comprising:
    determining an amount of oxygen consumed by said subject based on said volume of said respiratory gases and said concentration of oxygen in said respiratory gases.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030065273A1 (en) * 1999-08-02 2003-04-03 Mault James R. Metabolic calorimeter employing respiratory gas analysis
US20040015092A1 (en) * 2000-05-23 2004-01-22 Hans Pettersson Apparatus and method
US20040186390A1 (en) * 2002-08-01 2004-09-23 Lynette Ross Respiratory analyzer for exercise use
US20100083966A1 (en) * 2007-01-12 2010-04-08 Ulrich Jerichow Device for monitoring, controlling and/or regulating a gas composition
US8197417B2 (en) 2008-03-04 2012-06-12 Medical Graphics Corporation Metabolic analyzer transducer
US20130013281A1 (en) * 2010-03-31 2013-01-10 Koninklijke Philips Electronics N.V. Determining components of total carbon dioxide excreted by a subject

Families Citing this family (50)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070225612A1 (en) * 1996-07-15 2007-09-27 Mace Leslie E Metabolic measurements system including a multiple function airway adapter
US5915380A (en) 1997-03-14 1999-06-29 Nellcor Puritan Bennett Incorporated System and method for controlling the start up of a patient ventilator
US20040186389A1 (en) * 1998-02-05 2004-09-23 Mault James R Apparatus and method for determining a respiratory quotient
US6815211B1 (en) 1998-08-04 2004-11-09 Ntc Technology Oxygen monitoring methods and apparatus (I)
US6325978B1 (en) * 1998-08-04 2001-12-04 Ntc Technology Inc. Oxygen monitoring and apparatus
WO2001008554A1 (en) 1999-08-02 2001-02-08 Healthetech, Inc. Metabolic calorimeter employing respiratory gas analysis
EP1229833B1 (en) * 1999-11-16 2006-06-21 Cortex Biophysik GmbH Ergospirometry system for animals, especially horses or camels
US6873268B2 (en) 2000-01-21 2005-03-29 Medtronic Minimed, Inc. Microprocessor controlled ambulatory medical apparatus with hand held communication device
US6629933B1 (en) 2000-04-25 2003-10-07 Envitec Wismar Gmbh Method and device for determining per breath the partial pressure of a gas component in the air exhaled by a patient
US20040254501A1 (en) * 2000-08-11 2004-12-16 Mault James R. Achieving a relaxed state
US6581595B1 (en) * 2000-11-14 2003-06-24 Sensormedics Corporation Positive airway pressure device with indirect calorimetry system
US6632402B2 (en) 2001-01-24 2003-10-14 Ntc Technology Inc. Oxygen monitoring apparatus
US8208505B2 (en) * 2001-01-30 2012-06-26 Board Of Trustees Of Michigan State University Laser system employing harmonic generation
GB2372325B (en) 2001-02-16 2004-10-27 Nutren Technology Ltd Improvements in and relating to calculation of respiratory oxygen consumption
DE60225367D1 (en) * 2001-03-07 2008-04-17 Maquet Critical Care Ab expiration cassette
US20040236243A1 (en) * 2001-08-28 2004-11-25 Anders Eckerbom Device for quantitative analysis of respiratory gases, comprising a passive respiratory gas humidifyer, where rays of light are transmitted through a dehumified gas flow
US20040215096A1 (en) * 2001-08-28 2004-10-28 Anders Eckerbom Device at quantitative analysis of respiratory gases
US20030129578A1 (en) * 2001-10-26 2003-07-10 Mault James R. Method and system for early detection of infectious diseases or symptoms of bioterrorism attacks
US6976995B2 (en) 2002-01-30 2005-12-20 Cardiac Dimensions, Inc. Fixed length anchor and pull mitral valve device and method
WO2003084395A1 (en) * 2002-04-01 2003-10-16 Healthetech, Inc. System and method of determining an individualized drug administration dosage
US7024234B2 (en) * 2002-09-20 2006-04-04 Lyle Aaron Margulies Method and apparatus for monitoring the autonomic nervous system
WO2004041084A1 (en) * 2002-11-05 2004-05-21 Craig Thomas Flanagan Indirect calorimeter
US7887542B2 (en) 2003-01-15 2011-02-15 Biomet Manufacturing Corp. Method and apparatus for less invasive knee resection
US8551100B2 (en) 2003-01-15 2013-10-08 Biomet Manufacturing, Llc Instrumentation for knee resection
US7837690B2 (en) * 2003-01-15 2010-11-23 Biomet Manufacturing Corp. Method and apparatus for less invasive knee resection
US7749169B2 (en) * 2003-04-10 2010-07-06 Intoximeters, Inc. Handheld breath tester housing and mouthpiece
CA2430613A1 (en) * 2003-05-27 2004-11-27 Vacumetrics Inc. Portable vo2 meter
US7488324B1 (en) 2003-12-08 2009-02-10 Biomet Manufacturing Corporation Femoral guide for implanting a femoral knee prosthesis
EP1742572A4 (en) * 2004-05-04 2009-11-25 Univ Dalhousie Method of assessment of airway variability in airway hyperresponsiveness
US20060211981A1 (en) * 2004-12-27 2006-09-21 Integrated Sensing Systems, Inc. Medical treatment procedure and system in which bidirectional fluid flow is sensed
US20080146955A1 (en) * 2005-03-09 2008-06-19 Ngk Spark Plug Co., Ltd Respiration Sensor, Using Method of Respiration Sensor, and Respiration State Monitor
US20060217625A1 (en) * 2005-03-25 2006-09-28 Forrester Macquorn R Jr Mouthpiece for breath tester
US7451762B2 (en) * 2005-06-17 2008-11-18 Salter Labs Pressure sensing device with test circuit
WO2007059263A3 (en) * 2005-11-16 2009-05-22 Cardiopulmonary Technologies I Side-stream respiratory gas monitoring system and method
JP4591852B2 (en) * 2005-12-20 2010-12-01 富士医科産業株式会社 High resolution Human calorimeter
US8021310B2 (en) 2006-04-21 2011-09-20 Nellcor Puritan Bennett Llc Work of breathing display for a ventilation system
US7784461B2 (en) 2006-09-26 2010-08-31 Nellcor Puritan Bennett Llc Three-dimensional waveform display for a breathing assistance system
US20080119753A1 (en) * 2006-11-16 2008-05-22 Cardiopulmonary Technologies, Inc. Premature infant side-stream respiratory gas monitoring sensor
JP4998878B2 (en) * 2007-02-16 2012-08-15 日本光電工業株式会社 Carbon dioxide nasal mask
US20080294061A1 (en) * 2007-05-25 2008-11-27 Shiow-Chen Wang Health care gaming device and method using the same
US20090128344A1 (en) * 2007-11-21 2009-05-21 General Electric Company Systems, Apparatuses And Methods For Monitoring Physical Conditions Of A Bed Occupant
US8302602B2 (en) 2008-09-30 2012-11-06 Nellcor Puritan Bennett Llc Breathing assistance system with multiple pressure sensors
KR20110039168A (en) * 2009-10-09 2011-04-15 한국전자통신연구원 Face mask type vital signal measuring apparatus and vital signal management system using the same
US20110087084A1 (en) * 2009-10-09 2011-04-14 Electronics And Telecommunications Research Institute Face mask type vital signs measuring apparatus and vital signs management system using the same
US8335992B2 (en) 2009-12-04 2012-12-18 Nellcor Puritan Bennett Llc Visual indication of settings changes on a ventilator graphical user interface
US8924878B2 (en) 2009-12-04 2014-12-30 Covidien Lp Display and access to settings on a ventilator graphical user interface
US9119925B2 (en) 2009-12-04 2015-09-01 Covidien Lp Quick initiation of respiratory support via a ventilator user interface
US8499252B2 (en) 2009-12-18 2013-07-30 Covidien Lp Display of respiratory data graphs on a ventilator graphical user interface
US9262588B2 (en) 2009-12-18 2016-02-16 Covidien Lp Display of respiratory data graphs on a ventilator graphical user interface
US9950129B2 (en) 2014-10-27 2018-04-24 Covidien Lp Ventilation triggering using change-point detection

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1596798A (en) * 1924-09-23 1926-08-17 Brown Haydn Means for measuring respired air in testing lungs and for analogous purposes
US3774595A (en) * 1971-07-13 1973-11-27 G Cook Forced expirometer
US6309360B1 (en) * 1997-03-17 2001-10-30 James R. Mault Respiratory calorimeter
US6581595B1 (en) * 2000-11-14 2003-06-24 Sensormedics Corporation Positive airway pressure device with indirect calorimetry system
US20040039295A1 (en) * 2002-08-23 2004-02-26 Olbrich Craig A. Multi-function sensor device and methods for its use
US7060036B2 (en) * 2001-02-16 2006-06-13 Nutren Technology Limited Respiratory oxygen consumption measuring device and method

Family Cites Families (126)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2630798A (en) 1953-03-10 Respiratory quotient and metabolism meter
US2826912A (en) 1948-12-27 1958-03-18 Kritz Jack Acoustic velocity measuring system
US2831348A (en) 1953-08-14 1958-04-22 Kritz Jack Apparatus for suppressing undesirable modes in ultrasonic flowmeters
US2869357A (en) 1954-06-17 1959-01-20 Kritz Jack Continuously indicating electroacoustic densitometer
US2911825A (en) 1955-06-14 1959-11-10 Kritz Jack Mass flow fluid measurement
US2920012A (en) 1955-09-01 1960-01-05 Warner Lambert Pharmaceutical Therapeutic compositions for inhibiting carbonic anhydrase activity
US2838399A (en) 1955-10-05 1958-06-10 Organic Chemical Corp Non-gushing carbonated beverages and process for preparing the same
US3250270A (en) 1962-09-19 1966-05-10 Bloom Walter Lyon Device and method for measuring the calories an individual expends
US3220255A (en) 1962-12-03 1965-11-30 Technology Inc Thermal mass flowmeter
US3212684A (en) 1963-07-03 1965-10-19 Orion Ab Fab Arrangement for a grease pump
US3306283A (en) 1964-02-27 1967-02-28 Univ Iowa State Res Found Inc Oxygen utilization analyzer
US3527205A (en) 1968-04-02 1970-09-08 William C Jones Respiration testing apparatus
US3523529A (en) * 1968-06-25 1970-08-11 Us Air Force Oxygen consumption computer
US3681197A (en) 1969-01-02 1972-08-01 Clarence T Smith Method and solution for maintaining biological activity in enzymes
FR2077827A1 (en) 1970-02-17 1971-11-05 Thomson Csf
US3725658A (en) 1971-01-18 1973-04-03 Trw Inc Apparatus and method for continuously detecting oxygen in a gas stream
US3726270A (en) 1971-09-20 1973-04-10 Syst Res Labor Inc Pulmonary information transmission system
US3938551A (en) 1972-01-17 1976-02-17 Henkin Melvyn Lane Anesthesia rebreathing apparatus
US3814091A (en) 1972-01-17 1974-06-04 M Henkin Anesthesia rebreathing apparatus
US4051847A (en) 1972-01-17 1977-10-04 Melvyn Lane Henkin Anesthesia rebreathing apparatus
US3834375A (en) 1972-04-12 1974-09-10 Del Mar Eng Lab Respiratory gas analyzer for measuring and displaying oxygen uptake in expired air
US4003396A (en) 1972-08-08 1977-01-18 Fleischmann Lewis W Proportional control closed circuit gas admission system
US3799149A (en) 1972-12-26 1974-03-26 Nasa Metabolic analyzer
US3895630A (en) 1973-06-04 1975-07-22 Del Mar Eng Lab Respiratory gas analyzer including a carbon dioxide and respiratory quotient computer
US3979480A (en) 1973-12-28 1976-09-07 Societa' Italiana Resine S.I.R. S.P.A. Process for the polymerization of formaldehyde
US3962917A (en) 1974-07-03 1976-06-15 Minato Medical Science Co., Ltd. Respirometer having thermosensitive elements on both sides of a hot wire
FR2324284B1 (en) 1975-09-18 1978-06-23 Synthelabo
DE2715228A1 (en) 1977-04-05 1979-02-22 Siemens Ag Device for heating and moistening a breathing gas
US4186735A (en) 1977-04-21 1980-02-05 Flood Michael G Breathing apparatus
US4188946A (en) 1977-10-07 1980-02-19 Rayburn Robert L Controllable partial rebreathing anesthesia circuit and respiratory assist device
US4197857A (en) 1978-04-06 1980-04-15 Research Development Corporation System for measurement of oxygen uptake and respiratory quotient
US4211239A (en) 1978-05-03 1980-07-08 University Of Utah Neonatal oxygen consumption monitor
US4221224A (en) 1978-06-29 1980-09-09 Intermountain Health Care Non-airtight pulmonary measuring device
US4233842A (en) * 1978-10-20 1980-11-18 University Of Utah Apparatus for measurement of expiration fluids
US4230108A (en) 1979-03-13 1980-10-28 Young Sharon L Apparatus and method for sealing esophageal entrance to trachea above and below
DK144800C (en) 1980-04-21 1982-10-25 Forenede Bryggerier As A process for recovering enzymes, preferably Cu, Zn-superoxide dismutase (SOD), catalase and carbonic anhydrase, from blood
US4440177A (en) 1980-07-03 1984-04-03 Medical Graphics Corporation Respiratory analyzer system
JPS5948106B2 (en) 1980-08-27 1984-11-24 Tokyo Shibaura Electric Co
US4359057A (en) 1980-09-30 1982-11-16 Giovanni Manzella Apparatus for measuring oxygen consumption and the exchange of other breathing gases
JPS5777914A (en) 1980-10-31 1982-05-15 Toshiba Corp Fluid measuring apparatus
US4368740A (en) 1980-11-03 1983-01-18 Binder Andy S Physiologic analyzer
US4386604A (en) 1981-02-27 1983-06-07 Daniel Hershey Determination of the basal metabolic rate of humans with a whole-body calorimeter
US4463764A (en) 1981-09-29 1984-08-07 Medical Graphics Corporation Cardiopulmonary exercise system
ES528947A0 (en) 1983-01-19 1986-01-16 Karolinska Inst Med Tek Procedure for non-invasive determination of blood pumping of the heart and corresponding arrangement
US4598700A (en) 1983-03-14 1986-07-08 Tamm Ulf S Apparatus for measuring pulse rate and pulmonary volume
US4572208A (en) 1983-06-29 1986-02-25 Utah Medical Products, Inc. Metabolic gas monitoring apparatus and method
US4619269A (en) 1983-06-29 1986-10-28 Utah Medical Products, Inc. Apparatus and method for monitoring respiratory gas
US4781184A (en) 1984-01-13 1988-11-01 Fife William P Closed circuit breathing apparatus and method of using same
FI78231C (en) 1984-11-21 1989-07-10 Instrumentarium Oy Maetanordning Foer metaboliska storheter connectable to a respirator.
DE3672879D1 (en) 1985-03-26 1990-08-30 Icor Ab Detection apparatus of the oxygen-shot of a man.
DE3581397D1 (en) 1985-04-01 1991-02-21 Cosmed Srl Portable atemueberwachungsgeraet for telemetry of measured values ​​from a data processing center.
US5040541A (en) * 1985-04-01 1991-08-20 Thermonetics Corporation Whole body calorimeter
US4648396A (en) 1985-05-03 1987-03-10 Brigham And Women's Hospital Respiration detector
US4756670A (en) 1986-10-17 1988-07-12 Andros Analyzers Incorporated Detecting method and apparatus using heat sensitive devices
US4955946A (en) 1986-12-11 1990-09-11 Marquette Gas Analysis Respiratory CO2 detector circuit with high quality waveform
US4914959A (en) 1987-04-24 1990-04-10 Den Norske Stats Oljeselskap A.S. Ultrasonic flow meter using obliquely directed transducers
US4796639A (en) 1987-11-05 1989-01-10 Medical Graphics Corporation Pulmonary diagnostic system
US4986268A (en) 1988-04-06 1991-01-22 Tehrani Fleur T Method and apparatus for controlling an artificial respirator
US5233996A (en) 1988-05-20 1993-08-10 Boc Health Care, Inc. Patient interfacing system and method to prevent water contamination
US4850371A (en) 1988-06-13 1989-07-25 Broadhurst John H Novel endotracheal tube and mass spectrometer
US5179958A (en) 1988-06-29 1993-01-19 Mault James R Respiratory calorimeter with bidirectional flow monitor
US5038792A (en) 1988-06-29 1991-08-13 Mault James R Oxygen consumption meter
US4917108A (en) * 1988-06-29 1990-04-17 Mault James R Oxygen consumption meter
US5178155A (en) 1988-06-29 1993-01-12 Mault James R Respiratory calorimeter with bidirectional flow monitors for calculating of oxygen consumption and carbon dioxide production
US5022406A (en) 1988-08-01 1991-06-11 Tomlinson Harold W Module for determining diffusing capacity of the lungs for carbon monoxide and method
CA2001798A1 (en) 1988-10-31 1990-04-30 Jerker Delsing Method and apparatus for measuring mass flow
US5060655A (en) 1988-11-15 1991-10-29 Hans Rudolph, Inc. Pneumotach
US5081871A (en) 1989-02-02 1992-01-21 The United States Of America As Represented By The Secretary Of The Department Of Health And Human Services Breath sampler
JPH0346137B2 (en) 1989-03-01 1991-07-15 Nippon Koden Kogyo Kk
US5072737A (en) 1989-04-12 1991-12-17 Puritan-Bennett Corporation Method and apparatus for metabolic monitoring
US4909259A (en) 1989-04-21 1990-03-20 Tehrani Fleur T Method and apparatus for determining metabolic rate ratio
US5069220A (en) 1989-05-26 1991-12-03 Bear Medical Systems, Inc. Measurement of gas concentration in exhaled breath
US5095913A (en) 1989-09-01 1992-03-17 Critikon, Inc. Shutterless optically stabilized capnograph
US5060506A (en) 1989-10-23 1991-10-29 Douglas David W Method and apparatus for monitoring the content of binary gas mixtures
DE69018271D1 (en) 1989-11-24 1995-05-04 Minco Ab Apparatus for examination of the lung function of a patient.
US5042501A (en) 1990-05-01 1991-08-27 Battelle Memorial Institute Apparatus and method for analysis of expired breath
US5161525A (en) 1990-05-11 1992-11-10 Puritan-Bennett Corporation System and method for flow triggering of pressure supported ventilation
US5363857A (en) 1990-05-22 1994-11-15 Aerosport, Inc. Metabolic analyzer
US5117674A (en) 1990-05-22 1992-06-02 Aerosport, Inc. Metabolic rate analyzer
US5060656A (en) 1990-05-22 1991-10-29 Aerosport, Inc. Metabolic rate analyzer
US5038773A (en) 1990-06-08 1991-08-13 Medical Graphics Corporation Flow meter system
US5042500A (en) 1990-06-18 1991-08-27 Medical Graphics Corporation Drying sample line
DE69131836T2 (en) 1990-09-19 2000-07-27 Univ Melbourne Parkville Control circuit for monitoring the arterial CO 2 content
US5095900A (en) 1991-01-22 1992-03-17 Mine Safety Appliances Company Respiration monitor
US5119825A (en) 1991-02-25 1992-06-09 Medical Graphics Corporation Multi-functional patient valve
DE69132126D1 (en) * 1991-06-27 2000-05-25 James R Mault Measuring device for the oxygen pickup
US5468961A (en) 1991-10-08 1995-11-21 Fisher & Paykel Limited Infrared gas analyser and humidity sensor
EP0550396B1 (en) 1992-01-03 2002-03-13 Artema Medical Ab Device for gas analysis
US5800360A (en) 1992-02-11 1998-09-01 Spectrum Medical Technologies, Inc. Apparatus and method for respiratory monitoring
US5309921A (en) 1992-02-11 1994-05-10 Spectrum Medical Technologies Apparatus and method for respiratory monitoring
EP0557658B1 (en) 1992-02-24 1997-05-07 Hewlett-Packard Company Raman spectroscopy of respiratory gases
US5355879A (en) 1992-09-28 1994-10-18 Brain Archibald Ian Jeremy Laryngeal-mask construction
CA2097363A1 (en) 1992-06-03 1993-12-04 Hideo Ueda Expired air examination device and method for clinical purpose
DE4222286C1 (en) 1992-06-03 1994-05-11 Reutter Georg Dr Ultrasonic spirometer
US5293875A (en) 1992-06-16 1994-03-15 Natus Medical Incorporated In-vivo measurement of end-tidal carbon monoxide concentration apparatus and methods
US5282473A (en) 1992-11-10 1994-02-01 Critikon, Inc. Sidestream infrared gas analyzer requiring small sample volumes
US5285794A (en) 1992-12-14 1994-02-15 Temple University Of The Commonwealth System Of Higher Education Respiratory gas monitor
US5303712A (en) 1993-01-25 1994-04-19 Medical Graphics Corporation Calibration method for single-breath carbon monoxide lung diffusing capacity test system
US5357972A (en) 1993-05-17 1994-10-25 Medical Graphics Corporation Disposable pneumotachograph flowmeter
DE4318690A1 (en) 1993-06-04 1995-01-05 Ndd Medizintechnik Gmbh Method for measuring the molar mass of gases or gas mixtures and apparatus for carrying out this method
DK0724723T3 (en) 1993-07-06 2000-10-23 Kjell Alving System for determination of Nivveauer NO in exhaled air and diagnostic methods for disorders related tilunormale NO-ni
US5462880A (en) 1993-09-13 1995-10-31 Optical Sensors Incorporated Ratiometric fluorescence method to measure oxygen
EP0646346A3 (en) 1993-09-30 1998-06-17 NDD Medizintechnik GmbH Device for measuring respiratory gas parameters
US5398695A (en) 1994-03-24 1995-03-21 Medical Graphics Corporation Cardiopulmonary performance analyzer having dynamic transit time compensation
JP3782123B2 (en) 1994-05-31 2006-06-07 住友ベークライト株式会社 Throat luminal cavity airway
DE9410661U1 (en) 1994-07-01 1994-10-13 Ndd Medizintechnik Gmbh Ultrasonic spirometer
US5570697A (en) 1994-07-15 1996-11-05 Vixel Corporation Sensor for analyzing molecular species
US5816246A (en) 1994-09-15 1998-10-06 Mirza; M. Zubair Electronic pocket spirometer
US5796009A (en) 1994-10-24 1998-08-18 Delsing; Jerker Method for measuring in a fluid with the aid of sing-around technique
US5632281A (en) 1995-02-06 1997-05-27 Rayburn; Daniel B. Non-invasive estimation of arterial blood gases
US5517313A (en) 1995-02-21 1996-05-14 Colvin, Jr.; Arthur E. Fluorescent optical sensor
US5932812A (en) 1995-05-22 1999-08-03 Delsing; Jerker Method and devices use in flow measurement
JPH0954040A (en) 1995-08-09 1997-02-25 Kdk Corp Method for optically measuring component in exhalation
US5676132A (en) 1995-12-05 1997-10-14 Pulmonary Interface, Inc. Pulmonary interface system
US5836300A (en) 1996-03-11 1998-11-17 Mault; James R. Metabolic gas exchange and noninvasive cardiac output monitor
US6010459A (en) 1996-04-09 2000-01-04 Silkoff; Philip E. Method and apparatus for the measurement of components of exhaled breath in humans
US5831175A (en) 1996-06-12 1998-11-03 Welch Allyn, Inc. Method and apparatus for correcting temperature variations in ultrasonic flowmeters
US5789660A (en) 1996-07-15 1998-08-04 Novametrix Medical Systems, Inc. Multiple function airway adapter
US5957858A (en) 1996-07-26 1999-09-28 Polestar Technologies, Inc. Systems and methods for monitoring relative concentrations of different isotopic forms of a chemical species
US5705735A (en) 1996-08-09 1998-01-06 Medical Graphics Corporation Breath by breath nutritional requirements analyzing system
US5834626A (en) 1996-11-29 1998-11-10 De Castro; Emory S. Colorimetric indicators for breath, air, gas and vapor analyses and method of manufacture
GB9705586D0 (en) 1997-03-18 1997-05-07 Smiths Industries Plc Laryngeal mask assemblies
US6044843A (en) 1997-05-28 2000-04-04 Nellcor Puritan Bennett Incorporated Moisture resistant airway adapter for monitoring constituent gases
US6302851B1 (en) * 1997-11-13 2001-10-16 Siemens-Elema Ab Method and apparatus for determining a pulmonary function parameter for gas exchange
US6162180A (en) * 1998-12-28 2000-12-19 Medtronic, Inc. Non-invasive cardiac monitoring system and method with communications interface
US6174289B1 (en) * 1999-05-28 2001-01-16 Orca Diagnostics Corporation Cardiopulmonary exercise testing apparatus and method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1596798A (en) * 1924-09-23 1926-08-17 Brown Haydn Means for measuring respired air in testing lungs and for analogous purposes
US3774595A (en) * 1971-07-13 1973-11-27 G Cook Forced expirometer
US6309360B1 (en) * 1997-03-17 2001-10-30 James R. Mault Respiratory calorimeter
US6581595B1 (en) * 2000-11-14 2003-06-24 Sensormedics Corporation Positive airway pressure device with indirect calorimetry system
US7060036B2 (en) * 2001-02-16 2006-06-13 Nutren Technology Limited Respiratory oxygen consumption measuring device and method
US20040039295A1 (en) * 2002-08-23 2004-02-26 Olbrich Craig A. Multi-function sensor device and methods for its use

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030065273A1 (en) * 1999-08-02 2003-04-03 Mault James R. Metabolic calorimeter employing respiratory gas analysis
US6955650B2 (en) * 1999-08-02 2005-10-18 Healthetech, Inc. Metabolic calorimeter employing respiratory gas analysis
US20040015092A1 (en) * 2000-05-23 2004-01-22 Hans Pettersson Apparatus and method
US20040186390A1 (en) * 2002-08-01 2004-09-23 Lynette Ross Respiratory analyzer for exercise use
US7108659B2 (en) * 2002-08-01 2006-09-19 Healthetech, Inc. Respiratory analyzer for exercise use
US20100083966A1 (en) * 2007-01-12 2010-04-08 Ulrich Jerichow Device for monitoring, controlling and/or regulating a gas composition
US8197417B2 (en) 2008-03-04 2012-06-12 Medical Graphics Corporation Metabolic analyzer transducer
US20130013281A1 (en) * 2010-03-31 2013-01-10 Koninklijke Philips Electronics N.V. Determining components of total carbon dioxide excreted by a subject
US9763601B2 (en) * 2010-03-31 2017-09-19 Koninklijke Philips N.V. Determining components of total carbon dioxide excreted by a subject

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