CA1167727A
Expired / Lapsed
CA
⏱️ 0.0 years remaining
Cannula
Assignee: Vas Cath Inc
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Filing: 1981-11-26
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Granted: 1984-05-22
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Expires: 2001-11-26
Abstract
Abstract ABSTRACT OF THE DISCLOSURE A dual lumen cannula particularly for use in haemodialysis by inserting the cannula into the subclavian or femoral vein of a patient to contemporaneously remove blood from the vein for treatment and to return treated blood to the vein downstream from the point of removal. The cannula includes a pair of lumens separated by a septum. Blood is withdrawn through one of the lumens and treated blood is returned through the other lumen. The cannula is formed from a flexible thermo-plastic material and is sufficiently flexible to permit bending to conform to the shape of the vein without damage or kinking. The cannula has a peripheral generally cylindrical wall with a septum extending between spaced locations on the interior surface of the wall to define a pair of discrete lumens and at least one of the lumens is deformed by increasing its wall thickness at its end to facilitate insertion.
Inventors
- 👤 Geoffrey S. Martin
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-10-23 00:20
CPC Classifications
A; A61; A61M; A61M25/00; A61M25/0021; A61M25/0023; A61M25/0026; A61M25/003; A61M5/00; A61M5/14; A61M5/158; A61M5/1582; A61M2025/0031; A61M2025/0037
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
76 words
A flexible cannula having a peripheral wall defining interior and exterior surfaces and a septum extending between spaced points on the interior surface to divide the cannula into a pair of discrete lumens, one end of the cannula being stiffened by deformation of both part of the peripheral wall defining one lumen and the septum adjacent this part of the peripheral wall to facilitate safe insertion into a patient without collapsing the end of the cannula.
Claim 2
Dependent Claim
76 words
A flexible cannula having a peripheral wall defining interior and exterior surfaces and a septum extending between spaced points on the interior surface to divide the cannula into a pair of discrete lumens, one end of the cannula being stiffened by deformation of both part of the peripheral wall defining one lumen and the septum adjacent this part of the peripheral wall to facilitate safe insertion into a patient without collapsing the end of the cannula.
Claim 3
Dependent Claim
22 words
A cannula according to claim 1 wherein the deformation of the septum seals the other of the lumens at the one end.
Claim 4
Dependent Claim
38 words
A cannula according to claim 2 wherein a plurality of holes are formed in the peripheral wall of the other of the lumens adjacent the one end to permit flow of blood into the other of the lumens.
Claim 5
Dependent Claim
31 words
A cannula according to claim 1 wherein the one lumen extends beyond the other of the lumens and the septum is deformed to provide a circular cross-section for the one lumen.
Claim 6
Dependent Claim
30 words
A cannula according to claim 4 wherein a plurality of holes are formed in the one lumen to increase the cross sectional area of this lumen at the one end.
Claim 7
Dependent Claim
68 words
A flexible cannula having first and second lumens defined by an outer wall and a septum separating the lumens, the first lumen terminating at an end having a generally cylindrical cross-section and having an increased wall thickness in the region of the tip to provide a tip stiffer than the remainder of the cannula and the second lumen having at least one communicating opening short of said end.
Claim 8
Dependent Claim
68 words
A flexible cannula having first and second lumens defined by an outer wall and a septum separating the lumens, the first lumen terminating at an end having a generally cylindrical cross-section and having an increased wall thickness in the region of the tip to provide a tip stiffer than the remainder of the cannula and the second lumen having at least one communicating opening short of said end.
Claim 9
Dependent Claim
50 words
A cannula as claimed in claim 6 in which the outer wall and the septum are deformed at said end such that the septum is in engagement with the outer wall to close the end of the second lumen and in which said communicating opening is in the outer wall.
Claim 10
Dependent Claim
33 words
A cannula as claimed in claim 6 in which the outer wall is cut away short of said end and where it forms part of the second lumen to provide said communicating opening.
Claim 11
Independent Claim
75 words
A method of increasing the stiffness of one end of a flexible cannula having a peripheral wall defined by continuous interior and exterior surfaces with a septum extending between spaced points on the interior surface to divide the cannula into a pair of discrete lumens, the method comprising the step of deforming the septum at the one end to merge the septum with the peripheral wall and to thereby provide a region of increased stiffness.
Claim 12
Independent Claim
75 words
A method of increasing the stiffness of one end of a flexible cannula having a peripheral wall defined by continuous interior and exterior surfaces with a septum extending between spaced points on the interior surface to divide the cannula into a pair of discrete lumens, the method comprising the step of deforming the septum at the one end to merge the septum with the peripheral wall and to thereby provide a region of increased stiffness.
Claim 13
Dependent Claim
54 words
A method according to claim 9 wherein said deformation is performed by forming said cannula from a thermo-plastic material, inserting a mandrel of desired shape into the one lumen, applying peripheral pressure to the wall, heating the wall to deform it to the shape of the mandrel, cooling the wall and removing the mandrel.
Claim 14
Dependent Claim
126 words
A cannula having a peripheral wall defined by continuous inner and outer surfaces, a septum extending between spaced points on said inner surface to divide the cannula into a pair of discrete lumens, each of the lumens having an opening adjacent one end of the cannula to permit flow of blood between a blood vessel in which the cannula is located and the lumen, the openings being spaced along the axis of the cannula to permit replacement of blood through one of the lumens downstream of removal of blood through the other of the lumens, the septum being deformed adjacent the one end to combine with the peripheral wall to provide the opening for said one lumen and to increase the axial stiffness of the cannula.
Claim 15
Dependent Claim
126 words
A cannula having a peripheral wall defined by continuous inner and outer surfaces, a septum extending between spaced points on said inner surface to divide the cannula into a pair of discrete lumens, each of the lumens having an opening adjacent one end of the cannula to permit flow of blood between a blood vessel in which the cannula is located and the lumen, the openings being spaced along the axis of the cannula to permit replacement of blood through one of the lumens downstream of removal of blood through the other of the lumens, the septum being deformed adjacent the one end to combine with the peripheral wall to provide the opening for said one lumen and to increase the axial stiffness of the cannula.
References Cited (Backward Citations)
No citation records indexed.
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