Patent US3898987A successfully refreshed from Google Patents.
US3898987A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Breathing responsive device and method
Assignee: Individual
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Filing: 1973-10-09
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Granted: 1975-08-12
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Expires: 1993-10-09
Abstract
Abstract A smooth, accurately spherical, lightweight ball is located in a smooth, accurately cylindrical glass tube. The ball forms a nearly gas-tight seal with the tube wall, but is free to move easily in the tube in response to small gas pressure changes on the ball. The tube is connected to receive the breath-induced pressure changes during breathing of a medical patient so as to indicate the instantaneous or ''''tidal'''' volume of breathing with a high degree of accuracy and sensitivity. The tube is isolated from direct contact with the breath of the patient by a thin bulbous rubber membrane or plastic bag in a chamber. One side of the membrane or the exterior of the bag is connected in the breathing circuit of the patient so that the bag or membrane tends to fill and cause the ball to rise in the tube when the patient inhales, and tends to empty and cause the ball to fall in the tube when the patient exhales. The device can be used to indicate the very small tidal volumes caused by the patient''s diaphragm activity even when the patient is nearly completely paralyzed from the use of relaxant drugs used during surgery. The device can be connected so as not to indicate the volume of flow from a ventilator device if such a device is used in the breathing circuit. The volume of the bag or membrane is selected for each patient so that it will contain no more than the total ''''dead-space volume'''' of the patient''s tracheal-bronchial tract so as to prevent the rebreathing of alveolar air by the patient.
Inventors
- 👤 James O Elam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:07
CPC Classifications
A; A61; A61M; A61M16/00; A61B; A61B5/00; A61B5/08; A61B5/087; A61B5/0875; A61M16/0057; A61M16/0081; A61M16/021
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
170 words
A breathing volume indicating device comprising gas conduit meaNs for providing a substantially unimpeded guideway for a movable member, said conduit means having an elongated smooth internal surface, a movable gas-impervious lightweight member in said conduit means with a smooth outer surface and external dimensions slightly less than those of the interior of the conduit within relatively close tolerances so as to form a substantially gas-tight seal with said internal surface, means for communicating the pressure of breathing gases between a patient and said gas conduit means including means for isolating said internal surface and movable member from direct contact with said breathing gases, said isolating means further including a flexible membrane forming a chamber having a predetermined maximum volume, one side of said membrane communicating with said internal surface and said member, and the other side communicating with said gases, wherein said maximum volume is substantially equal to V, and V is given by the following equation: V T where T is the trachial-bronchial dead-space volume of the patient.
Claim 2
Dependent Claim
170 words
A breathing volume indicating device comprising gas conduit meaNs for providing a substantially unimpeded guideway for a movable member, said conduit means having an elongated smooth internal surface, a movable gas-impervious lightweight member in said conduit means with a smooth outer surface and external dimensions slightly less than those of the interior of the conduit within relatively close tolerances so as to form a substantially gas-tight seal with said internal surface, means for communicating the pressure of breathing gases between a patient and said gas conduit means including means for isolating said internal surface and movable member from direct contact with said breathing gases, said isolating means further including a flexible membrane forming a chamber having a predetermined maximum volume, one side of said membrane communicating with said internal surface and said member, and the other side communicating with said gases, wherein said maximum volume is substantially equal to V, and V is given by the following equation: V T where T is the trachial-bronchial dead-space volume of the patient.
Claim 3
Dependent Claim
21 words
A device as in claim 1 in which said movable member is a hollow sphere and said internal surface is cylindrical.
Claim 4
Dependent Claim
27 words
A device as in claim 1 in which said isolating means includes a further gas-tight chamber communicating between said patient and said other side of said membrane.
Claim 5
Dependent Claim
31 words
A device as in claim 1 in which said conduit means includes a valve seat at one end, said seat being shaped to form an air-tight seal with said movable member.
Claim 6
Dependent Claim
62 words
A device as in claim 1 including at least one outlet port to said conduit adjacent one end thereof, said conduit extending past said port by a distance at least equal to the longitudinal extent of said movable member so as to allow said movable member to pass by said port and permit gas to flow through said port and said conduit.
Claim 7
Dependent Claim
16 words
A device as in claim 1 in which said flexible membrane is a thin plastic bag.
Claim 8
Dependent Claim
28 words
A device as in claim 1 in which said gas conduit means is a vertical glass tube and said movable member is a hollow sphere with thin walls.
Claim 9
Dependent Claim
63 words
A device as in claim 1 including a ventilator, driving means for driving said indicating device to zero in response to exhalation by the patient, and for driving said indicator away from zero in response to inhalation by the patient, and means for conducting the pressure of ventilation to hold said indicating device at zero so as to indicate only natural breathing volume.
Claim 10
Dependent Claim
102 words
A device as in claim 8 in which said driving means includes a chamber, said indicating device being connected to said chamber, a stop at zero for said movable member, an inspiratory conduit connected to said chamber, an expiratory conduit connected between said ventilator and said chamber, and a check valve between said ventilator and said chamber, said check valve being adapted to close to prevent flow from said chamber to said ventilator, but to open to permit flow from the ventilator to the chamber only after a predetermined volume of gas has been withdrawn from said chamber through said inspiratory conduit.
Claim 11
Independent Claim
114 words
A device for indicating the breathing volume of a patient, said device comprising a precisely cylindrical elongated guide member, gas conduit means at the ends of said guide member for providing substantially umimpeded flow of gases to and from the interior of said cylindrical guide member, means for conducting gases to and from the patient and one of said gas conduit means, the other of said conduit means being open to the atmosphere, and a precisely spherical hollow indicator member movably positioned within said guide member and having external dimensions slightly less than those of the interior of the guide member within relatively close tolerances so as to form a substantially gas-tight seal therewith.
Claim 12
Independent Claim
114 words
A device for indicating the breathing volume of a patient, said device comprising a precisely cylindrical elongated guide member, gas conduit means at the ends of said guide member for providing substantially umimpeded flow of gases to and from the interior of said cylindrical guide member, means for conducting gases to and from the patient and one of said gas conduit means, the other of said conduit means being open to the atmosphere, and a precisely spherical hollow indicator member movably positioned within said guide member and having external dimensions slightly less than those of the interior of the guide member within relatively close tolerances so as to form a substantially gas-tight seal therewith.
Claim 13
Dependent Claim
17 words
A device as in claim 10 in which said movable member is a very thin-walled metal sphere.
Claim 14
Dependent Claim
145 words
A breathing indicator device comprising an elongated tube with a smooth internal surface, a thin-wAlled, lightweight smooth ball in said tube forming a substantially air-tight seal with said internal surface, one end of said tube being open to the atmosphere, at least one port in said tube at a location spaced from said one end, a chamber an inspiratory breathing conduit, an expiratory breathing conduit, a flexible membrane in said chamber, further conduit means for conducting of said membrane and between said inspiratory breathing conduit and the other side of said membrane, inlet means for connecting said chamber to receive gas from said expiratory breathing conduit and from a fresh gas source, and a check valve means associated with said expiratory conduit for blocking flow from said chamber but permitting flow into said chamber after a predetermined volume of gas has been removed from chamber.
Claim 15
Dependent Claim
145 words
A breathing indicator device comprising an elongated tube with a smooth internal surface, a thin-wAlled, lightweight smooth ball in said tube forming a substantially air-tight seal with said internal surface, one end of said tube being open to the atmosphere, at least one port in said tube at a location spaced from said one end, a chamber an inspiratory breathing conduit, an expiratory breathing conduit, a flexible membrane in said chamber, further conduit means for conducting of said membrane and between said inspiratory breathing conduit and the other side of said membrane, inlet means for connecting said chamber to receive gas from said expiratory breathing conduit and from a fresh gas source, and a check valve means associated with said expiratory conduit for blocking flow from said chamber but permitting flow into said chamber after a predetermined volume of gas has been removed from chamber.
Claim 16
Dependent Claim
29 words
A device as in claim 8 in which said membrane is a polyethylene bag, and means for releasably securing said bag in place to accommodate replacement of the bag.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |