US3742939A - Method and apparatus for determining respiratory airway resistance - Google Patents

Method and apparatus for determining respiratory airway resistance Download PDF

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Publication number
US3742939A
US3742939A US00118280A US3742939DA US3742939A US 3742939 A US3742939 A US 3742939A US 00118280 A US00118280 A US 00118280A US 3742939D A US3742939D A US 3742939DA US 3742939 A US3742939 A US 3742939A
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measuring
breath
volume
pressure
person
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W Sayer
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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/08—Measuring devices for evaluating the respiratory organs
    • A61B5/091—Measuring volume of inspired or expired gases, e.g. to determine lung capacity
    • A61B5/093—Measuring volume of inspired or expired gases, e.g. to determine lung capacity the gases being exhaled into, or inhaled from, an expansible chamber, e.g. bellows or expansible bag
    • A61B5/0935—Recording apparatus specially adapted therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/08—Measuring devices for evaluating the respiratory organs
    • A61B5/085—Measuring impedance of respiratory organs or lung elasticity

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  • FIG 5 ATTORNEYS PATENIEDJULB' 1975 saw a RF 4' mvsmoa WILLIAM -J. SAYER BYW Mfm
  • FIG 8 ATTORNEYS PATENTEI] JUL 3 I975 SHEEFMBFQ INVENTOR. WILLIAM J. S Em,
  • Atmospheric pressurepressure in the oropharynx/ flow has been a difficult task, particularly because the pharyngeal pressure (pressure in the nasopharynx) varies substantially during the inspirationrespiration cycle. Also, the simple linear relationship between pressure and flow to yield the airway resistance has been proven invalid as hysteresis occurs at very low and very high pressures.
  • a mask with selected inlet members measures pharyngeal pressure and pressure at the inlet to the nostrils during breathing, but without measuring volume.
  • Patent provides a rather complex instrument for measuring nasal airway resistance. Air flow is indirectly measured by looking at a pressure differential. The device appears to be an elaborate successor to the 1939 method, and because it tests over a wide pressure range it suffers from the same inaccuracies.
  • the pharyngeal pressure is monitored during a patients expiratory or inspiratory phase and when the pressure fits within prescribed limits the nasal or tracheobronchial air flow is measured and recorded.
  • the nasal or tracheobronchial airway resistance may then be calculated by dividing the difference between atmospheric pressure and the selected pharyngeal pressure by the air flow.
  • FIG. 1 is a schematic side view of the apparatus of the present invention as used with a patient.
  • FIG. 2 is a perspective view of a two-way valve forming a portion of the apparatus of the present invention.
  • FIG. 3 is a schematic end view of a portion of the apparatus of the present invention.
  • FIG. 4 is a perspective view of a three-way stop-cock valve forming a portion of the apparatus of the invention.
  • FIG. 5 is a graph of air volume per unit of time (air flow) generated by the kymograph and pen that forms a portion of the apparatus of the invention.
  • FIG. 6 is a schematic view'of a portion of the apparatus having a modified face mask as used with a patient.
  • FIG. 7 is a side elevation view of a mouthpiece adapted for use in measuring tracheobronchial airway resistance.
  • FIG. 8 is a schematic end view of a portion of the apparatus of FIG. 3 modified for measurement of tracheobronchial airway resistance.
  • FIG. 9 is a schematic view of the mouthpiece of FIG. 7 as used with a patient to measure tracheobronchial airway resistance.
  • FIG. 10 is a schematic end view of the apparatus of FIG. 8 modified to include a pair of gauge switches.
  • FIGS. 1 and 3 of the drawings a conventional spirometer 2 and kymograph 4 is shown supported on suitable base means 6.
  • a suitable spirometer and kymograph is the Warren E. Collins, Inc., Respirometer" No. P-9OO described in that companys 1966 catalog.
  • the Collins Respirometer may be used virtually as provided or if less resistance to air flow is desired it is modified by removing the inner soda lime cannister and rubber flutter valve.
  • Either device, for which any suitable equivalent means may be substituted, is essentially a source of air, the volume of which can be accurately measured with respect to time.
  • the bell 8 is filled with air when it is raised by the chain and counterbalance 10.
  • the three-way stop-cock valve 12 is rotated to permit room air to be drawn through tube 14 to fill the bell 8.
  • Tube 16 is in parallel to tube 14 and could be eliminated if desired. Tubes 14 and 16 are supported by a pair of flexible goose-neck supports 18 and 20.
  • the kymograph 4 has a removable paper chart 22 mounted on a motor-driven cylinder 26 and a moving pen 24 for marking thereon. As described hereinafter, the cylinder 26 is driven only when the patients pharyngeal pressure is within the prescribed limits, thus creating a chart record only during those time periods.
  • Tubes I4 and 16 are joined in a two-way valve 28, shown in greater detail in FIG. 2.
  • openings 32, 24 and 36 are connected in a closed system, thus connecting tubes 14 and 16 together to tube 40.
  • tubes 14 and 16 are connected together in a closed system and tube 40 at opening 36 is open to the room air via slot 42.
  • Tube 40 is attached via a coupling 42 to a scuba-type face mask 44 that fits over the patients nose in an air-tight manner.
  • a disposable mouthpiece 46 is placed into the patients mouth, over his tongue, and is connected to a tube 48 that may be of relatively small diameter because its purpose is to conduct the pharyngeal pressure, as present in the mouth, to a combination meter and switching device 50.
  • Device 50 has a pressure reading needle 52 and a pair of adjustable needles 54 for setting the desired pressure range. When the patients pharyngeal pressure read by needle 52 is within the limits as set by needles 54, then device 50 closes a switch to activate the kymograph motor. As the motor turns cylinder 26, the volume of air present in spirometer 2 is recorded by pen 24. As will be explained below, the record on chart 22 will provide the data necessary to calculate the nasal airway resistance of the patient.
  • Device 50 is a commercially available product marketed as a photohelic gauge switch by Dwyer Instruments, Inc., of Michigan City, Ind., as described in U.S. Pat. No. 3,397,319 to JP. Locke.
  • the device 50 has both positive and negative pressure inputs.
  • valve 28 In inspiratory nasal airway measurement operation, valve 28 is rotated to connect tubes 14 and 16 together and to open tube 40 to the room air. Mask 44 may be placed on the patient at this time since room air is available at the mask. Valve 12 is rotated to open tube 12 to the room air. Bell 8 is raised to fill the spirometer 2 with room air and then valve 12 is rotated to provide a closed path between the spirometer 2 and valve 28.
  • the patient is instructed to breath in through his nostrils while at the same time holding mouthpiece 46 in his mouth with his mouth closed around it. He is instructed to exhale through his mouth around the mouthpiece, holding the mouthpiece in place with his teeth. The patient is allowed to practice this before the actual recording procedure is begun.
  • the patient is also instructed to practice inhaling so as to provide a pharyngeal pressure falling within the limits set on device 50. Since the meter face of device 50 is visible to the patient he may watch it until he achieves the desired pressure. In actual practice it has been found that patients can achieve the desired pressure after a relatively brief period of practice.
  • the linear relation-ship be tween pressure and flow expressed in the equation.
  • R P Pp/ V/t where R is the nasal airway resistance, P0 is the atmospheric pressure, Pp is the pharyngeal pressure, and V]: is the volume of air per unit of time, is most valid in the range of about to 35 mm I-I,0.
  • valve 28 may be rotated to connect the spirometer air supply to the patients face mask via tubes 14, I6 and 40. As the patient inhales a chart of the spirometer volume level will be recorded whenever the pharyngeal pressure measured by device through tube 48 and mouthpiece 46 is within the prescribed range.
  • expiratory nasal airway measurements may be made, although most patients find the inspiratory measurements to be more comfortable. Also, there is less air leakage around the face mask during inspiratory measurements. Expiratory nasal airway measurements are made in a manner identical to the taking of inspiratory measurements except that the patient breathes out through his nostrils while holding mouthpiece 46 in his mouth with his mouth closed around it. The patient breathes in by holding the mouthpiece between his teeth and inhaling through his mouth around the mouthpiece. Tube 48 must be connected to the positive pressure input of pressure gauge 50 during expiratory measurements. A
  • FIG. 5 An actual reproduction of a patients chart of spirometer air volume versus time is shown in FIG. 5.
  • the iongest straight lines indicate periods in which the patient achieved continuous inhalation within the prescribed pharyngeal pressure limits for the longest times.
  • the longest straight line is chosen, preferably lasting 1% seconds or more, and the angle to the horizontal is measured to derive the slope of the line from which the volume per unit time can be calculated.
  • the nasal resistance is then the average pressure between the two limits set on device 50 divided by the volume per unit time taken from the chart.
  • the practitioner need only deal with the volume per unit time since it will be related to nasal resistance by a constant.
  • each nostril in turn to provide resistance data for the nasal airway with both nostrils uncovered, the left covered, and the right covered.
  • the nostrils may be covered by using cellophane tape or the like, being careful not to deform the nostril.
  • a clock in conjunction with the apparatus so that the operator may record the times at which the data was taken. It will be apparent that in a computerized version of the invention that time could be included along with the data taken.
  • FIG. 6 shows a modified face mask that may be used with the apparatus of FIGS. 1 and 3.
  • Mask 60 is hand-held by the patient and is advantageously used with patients who wear glasses or who feel uneasy with the mask strapped to their head.
  • Tube 40 as in FIG. 1 is connected via a coupling 62 to the mask 60.
  • Tube 48 as in FIG. 1 is connected to a mouthpiece 66 that passes through an air-tight fitting 64 in the mask 66.
  • the mask 60 is held firmly by the patient over his nose and mouth with mouthpiece 66 in his mouth.
  • the assembly functions in like manner to mask 44 and mouthpiece 46 of FIG. 1.
  • Tube 40 carries air to or from the nose just as it does with mask 44.
  • a relief valve (not shown) could be incorporated in the mask so that the patient could continually hold the mask against his face.
  • FIGS. 7-10 relate to an embodiment of the invention adapted for measuring tracheobronchial airway resistance.
  • FIG. 7 shows a side elevation view of a mouthpiece 68 adapted for measuring tracheobronchial airway resistance.
  • An air hose such as tube 40 (in FIG. 8) is connected to the right end of the mouthpiece.
  • a tube 72 (see also FIG. 8) for measuring pressure is connected to a tap 70 in the periphery of the mouthpiece.
  • FIG. 8 shows a modification of FIGS. 1 and 3 adapted for tracheobronchial measurements.
  • the mouthpiece 68 of FIG. 7 is employed with the apparatus of FIG. 8.
  • Pressure gauge 50 has two inputs: for measuring negative and positive pressures.
  • Tube 78 connects to one input and tube 76 connects to the other input.
  • a solenoid operated electric switch 73 connects the pressure measuring line 72 to one of the tubes 76 or 78 depending on whether or not electric leads 74 are energized.
  • the apparatus can measure pressure during expiration (positive pressure) or inspiration (negative pressure).
  • FIG. 9 shows a patient using the mouthpiece of FIG. 7 as it is used for tracheobronchial airway measurements.
  • a nose clamp 80 is placed over the patients nose to prevent any nasal airflow.
  • the switch 73 is selected to connect tube 72 to the negative input of gauge 50.
  • the patient breathes in through his mouth and attempts to maintain a pressure within the preselected range on gauge 50 in a manner analogous to the taking of nasal measurements.
  • the pressure measured by tube 72 is the pharyngeal pressure as in the nasal measurements and the measurement is still a differential pressure; the other pressure being the atmospheric pressure that surrounds the lungs, against which the lungs must work.
  • the same equations and computations are used to calculate the tracheobronchial airway resistance.
  • the switch 73 is changed to connect pressure tube 72 to the positive pressure input of gauge 50 and the patient attempts to maintain the preset pressure on gauge 50 when he breathes out.
  • the patient breathes around the mouthpiece while holding it in place with his teeth when a measurement is not being taken.
  • FIG. 10 shows a further modification of the embodiment of FIG. 8.
  • a pair of photohelic pressure gauge switches 50 and 51 are used in conjunction with a Y connection 75 and tubes 76 and 78.
  • Gauge 50 has tube 76 connected to its negative input and gauge 51 has tube 78 connected to its positive input.
  • This arrangement is desirable in taking tracheobronchial measurements when the pressures achievable by the typical patient are different for expiration and inspiration. By using two gauges, the pressure range need not be reset when changing from expiration to inspiration measurements. It has been found that when using two photohelic gauge switches, a simple Y connection may be used in lieu of a manual or solenoid switch in the pressure measuring line. When a single photohelic gauge switch is used, the pressure lines must be switched from the negative to positive input.
  • any means providing a measurable source of air supply such as a pneumotachograph may be substituted for the spirometer 2.
  • the recordation of the air supply volume with respect to time can be achieved by devices other than the kymograph 4.
  • such recordation could be done on an X-Y plotter, a storage-type oscilloscope, or the data could be stored in an analog or digital memory device.
  • the photohelic switch could be replaced by another pressure measuring arrangement and apparatus wherein a selected pressure range provides a control signal.
  • the computation of the nasal resistance may be carried out by a programmed machine such as an analog or digital computer. Therefore, the invention is to be limited only by the scope of the appended claims.
  • a method of deriving data for use in calculating nasal or tracheobronchial airway resistance of a person 1 comprising the simultaneous steps of measuring and recording the volume of air freely inspired or expired during a breath through either the mouth or nasal passages of a person,
  • Apparatus for deriving data for use in calculating nasal or tracheobronchial airway resistance of a person comprising means for measuring and recording the volume of air freely inspired or expired during a breath through either the mouth or nasal passages of a person,
  • means for measuring and recording the time during said breath means responsive to said means for measuring the pharyngeal pressure to actuate said means for measuring and recording the volume of air and said means for measuring and recording time only when the volume of air per unit time is substantially constant.
  • Apparatus according to claim 3 wherein the means for measuring and recording the volume of air includes:
  • substantially air-tight mask means adapted to fit over the nostrils or mouth of the person
  • Apparatus according to claim 4 wherein the means for measuring pharyngeal pressure comprises:
  • tube means for connecting said mouthpiece to said pressure measuring means.
  • Apparatus according to claim 5 wherein the means for measuring and recording time during the breath comprises a kymograph pen and ink chart recorder.
  • a method of determining the nasal or tracheobronchial airway resistance of a person comprising the simultaneous steps of measuring and recording the volume of air freely inspired or expired during a breath through either the R P Pp] V/t mouth or nasal passages of a person, where R is the nasal airway resistance, P0 is the atmomeasuring and recording time during the breath, spheric pressure, Pp is the average pharyngeal pressure measuring the pharyngeal pressure of the person durduring the breath and V]: is the volume of air per unit ing the breath, selecting the measured volume and time in ired during the breath, time where the volume o ai per Unit t is 8.

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US00118280A 1971-02-24 1971-02-24 Method and apparatus for determining respiratory airway resistance Expired - Lifetime US3742939A (en)

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JP (1) JPS5638219B1 (enExample)
CA (1) CA949771A (enExample)
DE (1) DE2208524A1 (enExample)
FR (1) FR2127745A5 (enExample)
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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USD246599S (en) * 1975-07-28 1977-12-06 Puritan-Bennett Corporation Pulmonary diagnostic instrument unit
US6210345B1 (en) * 1999-10-04 2001-04-03 American Biosystems, Inc. Outcome measuring airway resistance diagnostic system
US6379316B1 (en) 1999-08-31 2002-04-30 Advanced Respiratory, Inc. Method and apparatus for inducing sputum samples for diagnostic evaluation
US20050166928A1 (en) * 2004-01-30 2005-08-04 Yandong Jiang Methods and devices for maintaining an open airway
US20070125380A1 (en) * 2005-11-22 2007-06-07 General Electric Company Respiratory monitoring with differential pressure transducer
US20070239087A1 (en) * 2005-10-14 2007-10-11 Hill-Rom Services, Inc. Variable stroke air pulse generator
US20080216843A1 (en) * 2004-01-30 2008-09-11 The General Hospital Corporation D/B/A Massachusetts General Hospital Methods and devices for relieving upper airway obstructions
US7621267B1 (en) * 2004-08-30 2009-11-24 Adams Phillip M Scuba mask purging apparatus and method
US8460223B2 (en) 2006-03-15 2013-06-11 Hill-Rom Services Pte. Ltd. High frequency chest wall oscillation system
US20170039872A1 (en) * 2015-08-04 2017-02-09 Benjamin Grabber Incentive Spirometer and Musical Instrument
US9795752B2 (en) 2012-12-03 2017-10-24 Mhs Care-Innovation, Llc Combination respiratory therapy device, system, and method
US12080401B2 (en) 2012-12-03 2024-09-03 Metrohealth Ventures Llc Combination respiratory therapy device, system and method

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59107399A (ja) * 1982-12-13 1984-06-21 リオン株式会社 鼻音化の程度を計測する方法
CN117531171B (zh) * 2023-12-22 2025-12-02 中国人民解放军陆军军医大学第一附属医院 一种呼气训练装置

Citations (6)

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US3036569A (en) * 1959-08-04 1962-05-29 John A Clements Lung-airway resistance meter
FR1508303A (fr) * 1966-11-23 1968-01-05 Appareil de mesure pour l'étude de la mécanique ventilatoire pulmonaire
US3410264A (en) * 1966-06-02 1968-11-12 Frederik Willem Steven Instrument for measuring total respiratory and nasal air resistance
US3516401A (en) * 1966-05-10 1970-06-23 Michele Dell Aira Multiple-spirometer respiration measuring device
DE1915959A1 (de) * 1969-03-28 1970-10-08 Siemens Ag Geraet zur Analyse des von einem Patienten ausgeatmeten Gasgemisches
US3621833A (en) * 1969-06-26 1971-11-23 Robert Crane Method and apparatus for automatically determining physiological parameters related to human breathing airway resistance and functional residual capacity

Patent Citations (6)

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Publication number Priority date Publication date Assignee Title
US3036569A (en) * 1959-08-04 1962-05-29 John A Clements Lung-airway resistance meter
US3516401A (en) * 1966-05-10 1970-06-23 Michele Dell Aira Multiple-spirometer respiration measuring device
US3410264A (en) * 1966-06-02 1968-11-12 Frederik Willem Steven Instrument for measuring total respiratory and nasal air resistance
FR1508303A (fr) * 1966-11-23 1968-01-05 Appareil de mesure pour l'étude de la mécanique ventilatoire pulmonaire
DE1915959A1 (de) * 1969-03-28 1970-10-08 Siemens Ag Geraet zur Analyse des von einem Patienten ausgeatmeten Gasgemisches
US3621833A (en) * 1969-06-26 1971-11-23 Robert Crane Method and apparatus for automatically determining physiological parameters related to human breathing airway resistance and functional residual capacity

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Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USD246599S (en) * 1975-07-28 1977-12-06 Puritan-Bennett Corporation Pulmonary diagnostic instrument unit
US6379316B1 (en) 1999-08-31 2002-04-30 Advanced Respiratory, Inc. Method and apparatus for inducing sputum samples for diagnostic evaluation
US7018348B2 (en) 1999-08-31 2006-03-28 Hill-Rom Services, Inc. Method and apparatus for inducing sputum samples for diagnostic evaluation
US20020087097A1 (en) * 1999-08-31 2002-07-04 American Biosystems, Inc. Method and apparatus for inducing sputum samples for diagnostic evaluation
US6415791B1 (en) 1999-10-04 2002-07-09 American Biosystems, Inc. Airway treatment apparatus with cough inducement
US6340025B1 (en) 1999-10-04 2002-01-22 American Biosystems, Inc. Airway treatment apparatus with airflow enhancement
US6910479B1 (en) 1999-10-04 2005-06-28 Advanced Respiratory, Inc. Airway treatment apparatus with bias line cancellation
WO2001024698A1 (en) * 1999-10-04 2001-04-12 Advanced Respiratory, Inc. Airway treatment apparatus
US6210345B1 (en) * 1999-10-04 2001-04-03 American Biosystems, Inc. Outcome measuring airway resistance diagnostic system
US20050166928A1 (en) * 2004-01-30 2005-08-04 Yandong Jiang Methods and devices for maintaining an open airway
US20050166929A1 (en) * 2004-01-30 2005-08-04 Massachusetts General Hospital Methods and devices for relieving upper airway obstructions
US8091554B2 (en) 2004-01-30 2012-01-10 The General Hospital Corporation Methods and devices for relieving upper airway obstructions
US20080216843A1 (en) * 2004-01-30 2008-09-11 The General Hospital Corporation D/B/A Massachusetts General Hospital Methods and devices for relieving upper airway obstructions
US7621267B1 (en) * 2004-08-30 2009-11-24 Adams Phillip M Scuba mask purging apparatus and method
US20070239087A1 (en) * 2005-10-14 2007-10-11 Hill-Rom Services, Inc. Variable stroke air pulse generator
US7785280B2 (en) 2005-10-14 2010-08-31 Hill-Rom Services, Inc. Variable stroke air pulse generator
US20070125380A1 (en) * 2005-11-22 2007-06-07 General Electric Company Respiratory monitoring with differential pressure transducer
US9259542B2 (en) * 2005-11-22 2016-02-16 General Electric Company Respiratory monitoring with differential pressure transducer
US8460223B2 (en) 2006-03-15 2013-06-11 Hill-Rom Services Pte. Ltd. High frequency chest wall oscillation system
US9968511B2 (en) 2006-03-15 2018-05-15 Hill-Rom Services Pte. Ltd. High frequency chest wall oscillation system
US11110028B2 (en) 2006-03-15 2021-09-07 Hill-Rom Services Pte. Ltd. High frequency chest wall oscillation system
US9795752B2 (en) 2012-12-03 2017-10-24 Mhs Care-Innovation, Llc Combination respiratory therapy device, system, and method
US10814082B2 (en) 2012-12-03 2020-10-27 Mhs Care-Innovation, Llc Combination respiratory therapy device, system and method
US12080401B2 (en) 2012-12-03 2024-09-03 Metrohealth Ventures Llc Combination respiratory therapy device, system and method
US20170039872A1 (en) * 2015-08-04 2017-02-09 Benjamin Grabber Incentive Spirometer and Musical Instrument
US9792831B2 (en) * 2015-08-04 2017-10-17 Benjamin Grabber Incentive spirometer and musical instrument

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CA949771A (en) 1974-06-25
FR2127745A5 (enExample) 1972-10-13
DE2208524A1 (de) 1972-09-28
GB1379857A (en) 1975-01-08
NL7202428A (enExample) 1972-08-28
JPS5638219B1 (enExample) 1981-09-04

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