US3841307A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Subepidermal cannular instrument and method for automated determination of bleeding time and blood loss
Assignee: Individual
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Filing: 1972-11-15
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Granted: 1974-10-15
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Expires: 1992-11-15
Abstract
Abstract A cannular medical instrument and an automated method is disclosed herein for accurately determining bleeding time and blood loss. The main body of the instrument is in many respects similar to an elongate hypodermic needle having a predetermined opening made in the side thereof near the tip defining cutting edges and leaving a ''''pickup'''' length of usually approximating less than 10 mm. Alternatively to the formation of the opening, the bevel of a standard hypodermic needle may be extended until the desired opening is present. The forward portion and tip of the tubular needle in use is inserted beneath the skin at an optimum location which may be subcutaneous or in another position subepidermal. The central and rear portion of the elongate tubular needle is disposed in use externally of the skin and has connection means for receiving a small conduit connected with a predetermined suction source for withdrawal of liquid. Closely combined with said hollow needle is a tubular branch connection element for supply of distilled water or other fluid at the area of the incision made and ''''pickup'''' area. Preferably this branch tubular connection is rigidly integrated with the main body or tubular needle and extends angularly thereto with a terminal connection for receiving a small supply conduit from a controlled source of distilled water or other liquid or fluid at a predetermined speed and volume. To this structure and the subepidermal insertion of the cannula, a pickup is made of mixed blood and distilled fluid at the predetermined incision area and the amount of blood loss is then measured electrically or electronically and the duration of reading is also recorded.
Inventors
- 👤 P Friedell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:45
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/02042
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
161 words
In a withdrawal system for determining bleeding time and blood loss, a pickup and withdrawal instrument comprising: an elongate cannular body having a pointed forward extremity for piercing skin and tissue, said body having an elongate side opening defined by a pair of parallel, longitudinal cutting edges and a rear shoulder to define a pickup and mixing area of predetermined dimension, and in communication with the interior of said body, manipulating handle means extending angularly from said body and disposed rearwardly of said pickup area to enable said cannular body to be turned and longitudinally projected substantially parallel to the skin surface after first penetration through the skin, said body having means at its rear portion for connection with a suction conduit to effect withdrawal of a mixture of emitted blood and a mixing and carrier liquid, and controlled liquid supply means having a discharge disposed in said pickup area for causing mixture of supplied liquid with blood in said area.
Claim 2
Dependent Claim
161 words
In a withdrawal system for determining bleeding time and blood loss, a pickup and withdrawal instrument comprising: an elongate cannular body having a pointed forward extremity for piercing skin and tissue, said body having an elongate side opening defined by a pair of parallel, longitudinal cutting edges and a rear shoulder to define a pickup and mixing area of predetermined dimension, and in communication with the interior of said body, manipulating handle means extending angularly from said body and disposed rearwardly of said pickup area to enable said cannular body to be turned and longitudinally projected substantially parallel to the skin surface after first penetration through the skin, said body having means at its rear portion for connection with a suction conduit to effect withdrawal of a mixture of emitted blood and a mixing and carrier liquid, and controlled liquid supply means having a discharge disposed in said pickup area for causing mixture of supplied liquid with blood in said area.
Claim 3
Dependent Claim
56 words
The structure and combination set forth in claim 1 wherein said liquid supply means includes a tube connectible with a flexible conduit for predetermined supply of liquid for mixing and carrying expelled blood, said tube having rigid connection with said body and having a discharge opening interiorly of said body and communicating with said pickup area.
Claim 4
Dependent Claim
77 words
The structure and combination set forth in claim 1 wherein said side opening of said body is elongate starting at a point close to the forward extremity point and extending rearwardly to an area-defining shoulder through a length within a range less than 10 mm, said opening defining an elongate slot having a width approximating 1 mm, and the discharge of said liquid supply means being opposed to said slot which defines said opening and pickup area.
Claim 5
Dependent Claim
64 words
The structure and combination set forth in claim 2 wherein said rigidly secured supply means-tube and the rear of said cannular body constitute a handle for manipulating said instrument to readily provide for insertion thereof subepidermally, and wherein the forward portion of said cannular body forwardly disposed of the juncture of said body with said tube is in operation inserted subepidermally for blood testing.
Claim 6
Dependent Claim
218 words
A pickup and withdrawal instrument for use in a system which provides for automated determination of bleeding time and blood loss, said instrument comprising an elongate cannular body having a pointed forward extremity for piercing skin and tissue, said body having a side opening disposed somewhat rearwardly of said piercing extremity for defining a mixing and pickup area of predetermined length and width, said body having means at its rear portion for connection with a suction conduit to effect withdrawal of a mixture of emitted blood and a mixing and carrier liquid, controlled liquid supply means having a discharge disposed in said pickup area for causing mixture of supplied liquid with blood in said area, said instrument comprising part of a system which employs an electronic instrument for measuring electrical conductivity of the flowing mixture of blood and liquid withdrawn from said body, and wherein, as electrical sensors for said instrument, the tip portion of said body is constructed of an electrically conductive metal and the rear portion of said body is also constructed of an electrically conductive metal, and the interconnecting medial portion of said body is constructed of a substantially rigid material having substantially no electric conductive qualities, and electric conductors extending from said forward and rearward portions of said body to terminals of said instrument.
Claim 7
Dependent Claim
218 words
A pickup and withdrawal instrument for use in a system which provides for automated determination of bleeding time and blood loss, said instrument comprising an elongate cannular body having a pointed forward extremity for piercing skin and tissue, said body having a side opening disposed somewhat rearwardly of said piercing extremity for defining a mixing and pickup area of predetermined length and width, said body having means at its rear portion for connection with a suction conduit to effect withdrawal of a mixture of emitted blood and a mixing and carrier liquid, controlled liquid supply means having a discharge disposed in said pickup area for causing mixture of supplied liquid with blood in said area, said instrument comprising part of a system which employs an electronic instrument for measuring electrical conductivity of the flowing mixture of blood and liquid withdrawn from said body, and wherein, as electrical sensors for said instrument, the tip portion of said body is constructed of an electrically conductive metal and the rear portion of said body is also constructed of an electrically conductive metal, and the interconnecting medial portion of said body is constructed of a substantially rigid material having substantially no electric conductive qualities, and electric conductors extending from said forward and rearward portions of said body to terminals of said instrument.
Claim 8
Dependent Claim
191 words
A new method for automated determination of bleeding time and blood loss which consists in: forming a penetration in capillary tissue subepidermally with a cannula to form an incision in said tissue of predetermined length and width, said cannula being provided with a piercing tip and a side opening spaced therefrom, said side opening having longitudinal cutting edges and at least one shoulder defining the boundaries thereof, said cannula being inserted into said tissue in a direction substantially parallel to the skin with the side opening facing away from the skin so that the incision is formed along the bottom surface of the penetration, said cannula further providing a mixing and pickup space in said penetration directly above said incision formed by the boundaries of said side opening, supplying a predetermined small flow of a mixing and carrier liquid to said pickup space, withdrawing from said pickup space a mixture of emitted blood and said liquid, and by instrumentation responsive to the mixture flow determining the time bleeding takes place before clotting of said incision and also determining electrically the quantity of blood emitted during said test and the flow pattern.
Claim 9
Dependent Claim
191 words
A new method for automated determination of bleeding time and blood loss which consists in: forming a penetration in capillary tissue subepidermally with a cannula to form an incision in said tissue of predetermined length and width, said cannula being provided with a piercing tip and a side opening spaced therefrom, said side opening having longitudinal cutting edges and at least one shoulder defining the boundaries thereof, said cannula being inserted into said tissue in a direction substantially parallel to the skin with the side opening facing away from the skin so that the incision is formed along the bottom surface of the penetration, said cannula further providing a mixing and pickup space in said penetration directly above said incision formed by the boundaries of said side opening, supplying a predetermined small flow of a mixing and carrier liquid to said pickup space, withdrawing from said pickup space a mixture of emitted blood and said liquid, and by instrumentation responsive to the mixture flow determining the time bleeding takes place before clotting of said incision and also determining electrically the quantity of blood emitted during said test and the flow pattern.
Claim 10
Dependent Claim
45 words
The combination of steps set forth in preceding claim 6 wherein said instrumentation includes in the withdrawn flow of emitted blood and carrier liquid, the passing therethrough of an electrical current with suitable sensors to determine change in the conductivity of the mixture during flow.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |