CA1114705A - Cannula and method for bidirectional blood flow - Google Patents
Cannula and method for bidirectional blood flowInfo
- Publication number
- CA1114705A CA1114705A CA307,492A CA307492A CA1114705A CA 1114705 A CA1114705 A CA 1114705A CA 307492 A CA307492 A CA 307492A CA 1114705 A CA1114705 A CA 1114705A
- Authority
- CA
- Canada
- Prior art keywords
- cannula
- hub
- needle
- hollow
- blood
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000000034 method Methods 0.000 title claims abstract description 13
- 230000017531 blood circulation Effects 0.000 title claims abstract description 8
- 230000002457 bidirectional effect Effects 0.000 title abstract description 3
- 239000012530 fluid Substances 0.000 claims abstract description 8
- 239000008280 blood Substances 0.000 claims description 49
- 210000004369 blood Anatomy 0.000 claims description 49
- 230000008878 coupling Effects 0.000 claims description 27
- 238000010168 coupling process Methods 0.000 claims description 27
- 238000005859 coupling reaction Methods 0.000 claims description 27
- 210000004204 blood vessel Anatomy 0.000 claims description 12
- 238000004891 communication Methods 0.000 claims description 5
- 238000006073 displacement reaction Methods 0.000 claims description 2
- 238000002347 injection Methods 0.000 claims description 2
- 239000007924 injection Substances 0.000 claims description 2
- 210000000748 cardiovascular system Anatomy 0.000 claims 6
- 230000004941 influx Effects 0.000 claims 1
- 206010016717 Fistula Diseases 0.000 description 7
- 230000003890 fistula Effects 0.000 description 7
- 238000010276 construction Methods 0.000 description 3
- 238000000502 dialysis Methods 0.000 description 3
- 229920001971 elastomer Polymers 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 230000002411 adverse Effects 0.000 description 2
- 230000002452 interceptive effect Effects 0.000 description 2
- 229920001084 poly(chloroprene) Polymers 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 1
- 239000005021 flexible packaging material Substances 0.000 description 1
- 230000036512 infertility Effects 0.000 description 1
- 210000003734 kidney Anatomy 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000005022 packaging material Substances 0.000 description 1
- 230000037361 pathway Effects 0.000 description 1
- 230000037368 penetrate the skin Effects 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 230000000452 restraining effect Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M5/00—Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
- A61M5/14—Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
- A61M5/158—Needles for infusions; Accessories therefor, e.g. for inserting infusion needles, or for holding them on the body
- A61M5/1582—Double lumen needles
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M25/00—Catheters; Hollow probes
- A61M25/01—Introducing, guiding, advancing, emplacing or holding catheters
- A61M25/0105—Steering means as part of the catheter or advancing means; Markers for positioning
- A61M25/0111—Aseptic insertion devices
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M25/00—Catheters; Hollow probes
- A61M25/0021—Catheters; Hollow probes characterised by the form of the tubing
- A61M25/0023—Catheters; Hollow probes characterised by the form of the tubing by the form of the lumen, e.g. cross-section, variable diameter
- A61M25/0026—Multi-lumen catheters with stationary elements
- A61M25/003—Multi-lumen catheters with stationary elements characterized by features relating to least one lumen located at the distal part of the catheter, e.g. filters, plugs or valves
- A61M2025/0031—Multi-lumen catheters with stationary elements characterized by features relating to least one lumen located at the distal part of the catheter, e.g. filters, plugs or valves characterized by lumina for withdrawing or delivering, i.e. used for extracorporeal circuit treatment
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M25/00—Catheters; Hollow probes
- A61M25/0021—Catheters; Hollow probes characterised by the form of the tubing
- A61M25/0023—Catheters; Hollow probes characterised by the form of the tubing by the form of the lumen, e.g. cross-section, variable diameter
- A61M25/0026—Multi-lumen catheters with stationary elements
- A61M2025/0039—Multi-lumen catheters with stationary elements characterized by lumina being arranged coaxially
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Hematology (AREA)
- Engineering & Computer Science (AREA)
- Veterinary Medicine (AREA)
- Anesthesiology (AREA)
- Public Health (AREA)
- Vascular Medicine (AREA)
- Biophysics (AREA)
- Pulmonology (AREA)
- Infusion, Injection, And Reservoir Apparatuses (AREA)
- Media Introduction/Drainage Providing Device (AREA)
- External Artificial Organs (AREA)
Abstract
Abstract of Disclosure A cannula and method for bidirectional blood flow, the cannula being constructed so as to provide a bifurcated flow path, each branch of the flow path independently communicating through telescoping cannulae and a veni-puncture needle initially projecting beyond the exterior cannula to facilitate venipuncture and thereafter being displaceable away from the venipuncture site to permit unobstructed simultaneous fluid flow in opposite directions through each of the bifurcated flow paths.
Description
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CANNULA AND METHOD FOR BIDIRECTIONAL BLOOD FLOW
Specification The present invention relates to a cannula for medical use and more particularly to a double lumen cannula for independently conducting fluids into and out of a venip~ncture site through two separate passageways.
Double lumen cannulae are well known in the art.
The best known advantage offered by double lumen cannulae is the ability to separately withdraw blood from a blood vessel and inject blood back into the same blood vessel through a single venipuncture or fistula.
The most common double lumen cannulae consist of a single tube with a horizontal division of the tube which places the lumen of the cannulae in immediate juxta-position. Unfortunately, however, the construction of such double lumen cannulae is expensive, time consuming and unreliable.
The least expensive and most reliable construction of the double lumen cannulae is in the form of concentric lumen disposed telescopically one within the other. Particularly when using cannulae for single needle dialysis, it is preferred to have one cannula lumen project substantially beyond the other. Attention is directed particularly to the common use of cannulae for single needle dialysis such as that disclosed and described in U.S. Patent 3,756,234. In single needle dialysis, it is highly desirable to withdraw blood from a patient, treat the blood with a hemodialyzer (artificial kidney) and return the blood to the patient
CANNULA AND METHOD FOR BIDIRECTIONAL BLOOD FLOW
Specification The present invention relates to a cannula for medical use and more particularly to a double lumen cannula for independently conducting fluids into and out of a venip~ncture site through two separate passageways.
Double lumen cannulae are well known in the art.
The best known advantage offered by double lumen cannulae is the ability to separately withdraw blood from a blood vessel and inject blood back into the same blood vessel through a single venipuncture or fistula.
The most common double lumen cannulae consist of a single tube with a horizontal division of the tube which places the lumen of the cannulae in immediate juxta-position. Unfortunately, however, the construction of such double lumen cannulae is expensive, time consuming and unreliable.
The least expensive and most reliable construction of the double lumen cannulae is in the form of concentric lumen disposed telescopically one within the other. Particularly when using cannulae for single needle dialysis, it is preferred to have one cannula lumen project substantially beyond the other. Attention is directed particularly to the common use of cannulae for single needle dialysis such as that disclosed and described in U.S. Patent 3,756,234. In single needle dialysis, it is highly desirable to withdraw blood from a patient, treat the blood with a hemodialyzer (artificial kidney) and return the blood to the patient
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~47~i5 through the same fistula in which the blood was withdrawn. Under such circumstances, it is desirable to return the blood a significant distance upstream from where the blood is aspirated so as to minimize the problem of admixing.
The problems with such telescopic construction are apparent when it is observed that both cannula must be used to penetrate the skin during venipuncture. Unless there is a smooth contour between -the interior and exterior cannula, the venipuncture is both difficult and painful. On the other hand, if the telescoping cannulae present an exteriorly smooth surface for venipuncture, there is insufficient passageway for fluid to flow easily between the lumen. The structure of a double lumen cannula lends itself admirably to the ability to aspirate blood from a downstream location and to return blood at an upstream location all through the same fîstula. However, until this present invention, structure and method for introducing a double lumen cannula into the bloodstream and for maintaining separate flow paths through a single fistula has not been known.
The present invention, including method and appa-ratus, provides bifurcated flow paths through coextensive cannulae, the cannulae being introduced into the blood vessel initially by a needle which is thereafter removed to facilitate unobstructed flow through the independent flow paths established at a single fistula.
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~47~i5 through the same fistula in which the blood was withdrawn. Under such circumstances, it is desirable to return the blood a significant distance upstream from where the blood is aspirated so as to minimize the problem of admixing.
The problems with such telescopic construction are apparent when it is observed that both cannula must be used to penetrate the skin during venipuncture. Unless there is a smooth contour between -the interior and exterior cannula, the venipuncture is both difficult and painful. On the other hand, if the telescoping cannulae present an exteriorly smooth surface for venipuncture, there is insufficient passageway for fluid to flow easily between the lumen. The structure of a double lumen cannula lends itself admirably to the ability to aspirate blood from a downstream location and to return blood at an upstream location all through the same fîstula. However, until this present invention, structure and method for introducing a double lumen cannula into the bloodstream and for maintaining separate flow paths through a single fistula has not been known.
The present invention, including method and appa-ratus, provides bifurcated flow paths through coextensive cannulae, the cannulae being introduced into the blood vessel initially by a needle which is thereafter removed to facilitate unobstructed flow through the independent flow paths established at a single fistula.
- 3 -It is, therefore, a primary object of the present invention to provide an improved doub:Le lumen cannula.
It is another primary object of ~he present invention to provide a method of aspirating blood and returning blood through separate flow paths and through a single fistula.
It is another primary object of the present invention ~to provide a novel double lumen cannula and method in whlch the needle is removed from the puncture site after venipuncture without adversely interfering with the blood flow paths.
Another valuable object of the present invention is the provision of structure and method for introducing an interior catheter unidirectionally through an exterior catheter.
In general terms, the present invention provides a cannula assembly comprising in combination: a bifurcated hub having two separate branches; a first hollow cannula mounted in the bifurcated hub at one of said branches; a second hollow cannula essentially coextensible with the first cannula and mounted on the hub at the other said branch; a venipuncture needle telescopically disposed within the first said cannula and projecting therebeyond to facilitate introduction of both the first and second said cannulae into a blood vessel, said venipuncture needle being displaceable through said hub away from the blood vessel after venipuncture so as to facilitate exposure of both the first and second said cannulae within the said blood vessel; and a first flow path defined by the fir.st said cannula and its corresponding branch of said hub and a second flow path defined by the second said cannula, the first and second flow paths being in fluid communication with extra-corporeal fluid lines and being separated one from the other so that simultaneous aspiration sf blood through one of the said ( ., :
flow paths and injection of blood through the other of the said flow paths is simultaneously accomodated.
These and other objects and features of the present invention will become more fully apparent from the following description and appended claims taken in conjunction with the accompanying drawings.
Figure 1 is a perspective view of one presently pre-ferred cannula embodiment of the invention.
Figure 2 is a cross-section taken along lines 2-2 of Figure 1.
Figure 3 is a cross-sectional elevation of the embodiment of Figure 1 illustrating the stylet needle in a partially removed position and illustrating the interior catheter as partially advanced through the cannula hub.
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Figure 4 is a cross-sectional elevation of the embodiment of Figure 1 illustrating the separate flow paths connected to appropriate extracorporeal blood circuitry.
Figure 5 is an enlarged cross-sectional elevation of another presently preferred embodiment similar to the embodiment of Figure 1 and illustrating a unidirectional flow control valve therein.
Figure 6 is a perspective illustration of another cannula embodiment with a reciprocating needle, the needle being illustrated in the forward most, initial position.
Figure 7 is a perspective illustration of the embodiment of Figure 6 with the needle in the retracted position.
Figure 8 is a cross section taken along lines 8-8 of Figure 7, Attention is now directed to the figures wherein like parts are designated with like numerals throughout.
With particular reference to Figure 1, the cannula assembly generally designated 10 comprises a cannula hub 12 preferably formed of a rigid plastic material. An exterior hollow cannula 14 is mounted wi~hin the hub 12 at the leading end 16 thereof as shown best in Figure 2.
The exterior cannula 14 projects forward of the hub 12 a discrete, predetermined distance and is tapered forwardly at the leading tip 18. If desired, apertures 20 may be formed in the exterior cannula 14 adjacent the leading tip 18 thereof. The hub 12 has a trailing end 22 ~ 7'~ ~
which, in the illustrated embodiment, is secured to a flexible sleeve 24. The flexible sleeve 24 is provided with an end plug 26 preferably formed of neoprene or other suitable material which is self-sealing.
The hub 12 has an internal throughbore 28 which opens at the trailing end 22 of the hub and is in direct internal communication with the interior of cannula 14.
The hub 12 is bifurcated at 30 so as to form a branch 32.
Branch 32 has a bore 34 which communicates directly with the bore 28 of the hub 12. The branch 32 is angularly related with respect to the hub 12 preferably at about 45 degrees or less. The branch 32 is provided with a neoprene self-sealing plug 36 through which interior cannula or catheter 38 passes in a manner hereinafter more fully described.
Referring again to Figure 2, an elongated stylet needle 40 is telescopically disposed through the entire length of the hub 12 and exterior cannula 14. The sharpened tip 42 of the needle 40 projects beyond the exterior cannula 14 so as to permit facile venipuncture and safe introduction of the exterior cannula 14 into a blood vessel according to conventional techniques. The trailing end 44 of the needle 40 is rigidly mounted within a needle hub 46. Preferably, the needle hub 46 defines a hollow interior 48 which communicates directly with the interior of the hollow needle 40. Thus, upon successful venipuncture, the needle hub 46 will reflect a blood flashback indicating successful venipuncture. -The needle is intended to pass immediately through the . .
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plug 26 in the position illustrated in Figure 2.
However, because the sleeve 24 is flexible in cvnfigu-ration, and in order to give stability to the cannula assembly 10 during venipuncture, a cylindrical housing 50 is mounted upon the needle hub 46 and telescopically circumscribes the sleeve 24 and the trailing end 22 of the hub 12. As shown best in Figure 1, the housing 50 has a plurality of keyways 52 adapted to receive a suitable detent 54. The detent 54 in cooperation with the keyway 52 locks the housing 50 temporarily in place upon the hub 12.
After venipuncture, the housing 50 may be rotated slightly about the axis of the needle 40 and retracted rearwardly as shown in Figure 3 until the needle has been removed from the exterior cannula 14. While the needle is in the advanced position illustrated in Figure 2, the throughbore 28 is substantially obstructed.
However, when the needle 40 is retracted to the position illustrated in Figure 3, at least that portion of the throughbore 28 which is forward of the intersection of bore 34 with bore 28 is unobstructed. When unobstructed, the interior catheter 38 may be advanced through the hollow of the exterior cannula 14 by digital manipulation. The catheter 38 defines a hollow passageway 56 which communicates openly with the female coupling 58. The length of catheter 38 is selected to project beyond the leading end 18 of cannula 14 when the catheter 38 is fully advanced through the bore 34. When desired, blood may be com~unicated through the passageway 56 of the interior cannula 38 by connecting a blood tubing ~o the female coupling 58. Because the catheter 38 will come in contact with the patient's blood, it may be desirable to maintain the sterility of the catheter 38. Accordingly, a suitable flexible packaging material 60 as schematically illustrated in broken lines in Figure 1 could be used. Conven-tional packaging material 60 which permits advancement of a catheter through a hub is known in the art and no further comment thereon is deemed necessary.
The method of using the catheter assembly embodi-ment of Figure 1 can best be understood by reference to Figures 3 and 4. With the needle in the fully advanced position illustrated in Figure 2, venipuncture is performed such that the exterior catheter 14 is inserted within a blood vessel to create a single fistul~.
Thereafter, the housing 50 is rotated slightly and the needle withdrawn to the position illustrated in Figure 3. Of course, if desired, the needle 40 may be com-pletely withdrawn through the plug 26, the memory of theplug 26 preventing the blood from spilling out of the hub 12. However, it may also be desirable to leave the needle in the position illustrated in Figure 3. In any event, after the needle has been withdrawn from the exterior cannula 14, the interior catheter 38 may be ~-advanced through the branch 32 until it projects a desired distance beyond the leading end 18 of the cannula 14. Thus, cannulae 14 and 38 are coextensive at least along the length of cannula 14. Notably, the ~ .,, "~ .
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external diameter of the catheter 38 is sufficiently less than the internal diameter of the cannula 14 that blood will flow easily therebetween. Accordingly, blood may be aspirated in the passageway between the cannula 14 and the catheter 38, through the bore 28, the hollow of the needle 40, the needle hub 46 and through extracorporeal blood circuitry (not shown) connected at 62. After the blood has traversed an extracorporeal blood circuit, it may then be returned through the coupling 58 and the passageway 56 within the interior catheter 38.
Note that blood may be withdrawn from and returned to the patient without creating an additional fistula and without otherwise modifying the structure of the catheter assembly 10. The withdrawal and return of blood may occur simultaneously or serially, as desired.
While the needle may be retained in the position illustrated in Figure 3, it has been found preferable to completely remove the needle 40 from the hub 12.
Removal is easily accommodated by withdrawing the needle from the plug 26, manually squeezing the flexible sleeve 24 to prevent outflow of blood, removing plug 26 and thereafter inserting the coupling 62 of the extracorporeal blood circuit directly into the sleeve 24. In this configuration, the risk that the needle may damage the interior catheter 28 or otherwise interfere with the flow of blood is eliminated. As pointed out in Figure 4, in this presently preferred embodiment, the interior catheter 38 may be of any desirable length and ~4~
will preferably project a substantial distance beyond the leading end 18 of the exterior catheter 14. Because the length of catheter 38 can be selected, any of a variety of distances between the leading tip 18 of cannula 14 and the leading tip of catheter 38 could be selected (see Figure 4).
Referring now to Figure 5, a modification of the embodiments of Figures 1-4 is illustrated. In Figure 5, a female Luer fitting 66 has been substituted for the rubber plug 36 as shown in Figure 2. The female Luer fitting will receive a male coupling 68 in press-fit relation to permit return of blood from the extra-corporeal blood circuit through the passageway 56 of the interior catheter 38.
In order to prevent blood within the throughbore 28 from escaping through the Luer fitting 66 as the catheter 38 is advanced, a unidirectional check ~alve 70 is provided in the branch 32. The check valve 70 is preferably made of a flexible rubber material through which the catheter 38 is easily passed in the forward direction. The valve 70 is a leaflet or duck-bill type valve.
Attention is now directed to another presently preferred cannula assembly embodiment generally desig-nated 80 and illustrated best in Figures 6-8. The cannula assembly 80 is intended to accomplish the same purpose as the assembly 10. More particularly, the assembly 80 comprises an exterior cannula 82 which is mounted at the forward end 84 of a cannula hub 86.
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, Preferably, the exterior cannula 82 is forwardly tapered at ~8 and defines an interior bore 90 (see Figure 8).
The bore 90 of the cannula 82 communicates directly with a recess 91 in the hub 86. The recess 91 opens at the trailing end 94 of the hub 86. Rubber sleeve 87 is nested within recess 91 and defines a throughbore 92 which tightly circumscribes needle 126 to form an air-tight seal as will hereinafter be more fully described.
An interior catheter or cannula 98 traverses the entire throughbore 92 and the bore 90 of exterior cannula 82. The leading end 100 of the catheter 98 projects substantially beyond the leading end 88 of cannula 82 as shown in both Figures 7 and 8. The trailing end of catheter 98 is mounted wi~hin coupling member 102, the coupling member 102 having a male Luer fitting 104 which is in direct alignment with the throughbore 92. The interior catheter 98 is hollow and opens directly into the female Luer coupling 106. The coupling member 102 is maintained in direct alignment and fixed axial spacial relationship with the hub 86 by a strut 108. It can be seen, therefore, that there is a discrete passageway from the leading tip 100 of the catheter 98 through the entire length of the catheter 98 to the coupling member 102.
The cannula hub 86 is bifurcated at 110 to form a branch 112. The branch 112 has a female Luer fitting 114 at its trailing end 116 into which a suitable coupling 120 from a conventional extracorporeal blood circuit is press-fit. The branch 112 has a hollow interior 122 which communicates directly with the bore 90 of exterior cannula 82. Accordingly, a discrete passageway exists through the bore 90 and hollow 122 to the coupling 120. In addition, a separate and discrete passageway exists through the hollow of interior catheter 198 to the trailing end of coupling member 102 and to a male coupling 124 press-fit therein.
In order to facilitate introduction of the coex-tensive cannulae 82 and 98, a venipuncture needle 126 is provided. The venipuncture needle 126 has a sharp beveled end 128 which, in the initial position illus-trated in Figure 6, projects through the interior of cannula 82 and telescopically around and beyond catheter 98. With reference to Figure 8, it can be appreciated that the needle 126 is reciprocably displaceable within the bore 92 of the sleeve 87. The sleeve 87 forms an air-tight seal with needle 126 so that negative pressure within the hub 86 and branch 112 will not draw air around the needle 126 into the blood within the hub.
The trailing end 128 of the needle 126 is firmly mounted to a shuttle 130, the shuttle having a rearwardly facing female fitting 132 which is selectively press-fit upon the male fitting 104 of coupling member 102 as illus-trated in Figure 8. Clearly, the location of the male fitting 104 and female fitting 132 could be reversed without adverse consequence. This press-fit coupling minimizes blood leakage around the needle 126 after venipuncture and forms an air seal for preventing air from entering the hub 86 when the interior of hub 86 is subjected to negative internal pressure.
The method of using the embodiment of Figures 6-8 is apparent from the drawing. Initially, the shuttle 130 is advanced forwardly until the needle 126 projects beyond the leading end 88 of the cannula 82 and substantially circumscribes and confines the interior catheter 98. By restraining the shuttle 130 in place with the fingers, the venipuncture can easily be made.
It is observed~ however, that the needle 126 will substantially fill the passageway in the throughbore 90 between the cannula 82 and the catheter 98.
Accordingly, blood will not flow through the bore 90 and hollow 122 in the branch 112 while the needle is in the forward position illustrated in Figure 6.
After venipuncture has been successfully accom-plished and the fistula established, the shuttle 130 may be manually displaced rearwardly and telescopically over the exposed portion of the interior catheter 98 until the shuttle 130 mates with the coupling member 102. In this mode, blood will freely flow between the cannulae 82 and 98, through the branch 112 and the extracorporeal blood circuit connected at 120. At the same time, blood may also flow through the hollow of the interior catheter 98 along the discrete flow path defined by the interior catheter 98 and through the coupling 124 to the extracorporeal blood circuit.
The length of the needle 126 and the strut 108 are selected so that when the shuttle 130 is in the rearmost position illustrated in Figures 7 and 8, the sharpened leading end 128 of the needle 126 will remain supported 7~S
by the cannula hub 86 but be fully retracted out of the pathway 122 so as to avoid interfering with blood flow.
Clearly, in the embodiments illustrated herein structure and method have been described which facili-tates successful cannulation of a blood vessel and, after cannulation, the displacement and/or removal of the sharpened needle to permit essentially simultaneous aspiration of blood from the patient and delivery of blood back to the patient through two discrete flow paths in the assembly.
The invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive and the scope of the invention is, there-fore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
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It is another primary object of ~he present invention to provide a method of aspirating blood and returning blood through separate flow paths and through a single fistula.
It is another primary object of the present invention ~to provide a novel double lumen cannula and method in whlch the needle is removed from the puncture site after venipuncture without adversely interfering with the blood flow paths.
Another valuable object of the present invention is the provision of structure and method for introducing an interior catheter unidirectionally through an exterior catheter.
In general terms, the present invention provides a cannula assembly comprising in combination: a bifurcated hub having two separate branches; a first hollow cannula mounted in the bifurcated hub at one of said branches; a second hollow cannula essentially coextensible with the first cannula and mounted on the hub at the other said branch; a venipuncture needle telescopically disposed within the first said cannula and projecting therebeyond to facilitate introduction of both the first and second said cannulae into a blood vessel, said venipuncture needle being displaceable through said hub away from the blood vessel after venipuncture so as to facilitate exposure of both the first and second said cannulae within the said blood vessel; and a first flow path defined by the fir.st said cannula and its corresponding branch of said hub and a second flow path defined by the second said cannula, the first and second flow paths being in fluid communication with extra-corporeal fluid lines and being separated one from the other so that simultaneous aspiration sf blood through one of the said ( ., :
flow paths and injection of blood through the other of the said flow paths is simultaneously accomodated.
These and other objects and features of the present invention will become more fully apparent from the following description and appended claims taken in conjunction with the accompanying drawings.
Figure 1 is a perspective view of one presently pre-ferred cannula embodiment of the invention.
Figure 2 is a cross-section taken along lines 2-2 of Figure 1.
Figure 3 is a cross-sectional elevation of the embodiment of Figure 1 illustrating the stylet needle in a partially removed position and illustrating the interior catheter as partially advanced through the cannula hub.
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Figure 4 is a cross-sectional elevation of the embodiment of Figure 1 illustrating the separate flow paths connected to appropriate extracorporeal blood circuitry.
Figure 5 is an enlarged cross-sectional elevation of another presently preferred embodiment similar to the embodiment of Figure 1 and illustrating a unidirectional flow control valve therein.
Figure 6 is a perspective illustration of another cannula embodiment with a reciprocating needle, the needle being illustrated in the forward most, initial position.
Figure 7 is a perspective illustration of the embodiment of Figure 6 with the needle in the retracted position.
Figure 8 is a cross section taken along lines 8-8 of Figure 7, Attention is now directed to the figures wherein like parts are designated with like numerals throughout.
With particular reference to Figure 1, the cannula assembly generally designated 10 comprises a cannula hub 12 preferably formed of a rigid plastic material. An exterior hollow cannula 14 is mounted wi~hin the hub 12 at the leading end 16 thereof as shown best in Figure 2.
The exterior cannula 14 projects forward of the hub 12 a discrete, predetermined distance and is tapered forwardly at the leading tip 18. If desired, apertures 20 may be formed in the exterior cannula 14 adjacent the leading tip 18 thereof. The hub 12 has a trailing end 22 ~ 7'~ ~
which, in the illustrated embodiment, is secured to a flexible sleeve 24. The flexible sleeve 24 is provided with an end plug 26 preferably formed of neoprene or other suitable material which is self-sealing.
The hub 12 has an internal throughbore 28 which opens at the trailing end 22 of the hub and is in direct internal communication with the interior of cannula 14.
The hub 12 is bifurcated at 30 so as to form a branch 32.
Branch 32 has a bore 34 which communicates directly with the bore 28 of the hub 12. The branch 32 is angularly related with respect to the hub 12 preferably at about 45 degrees or less. The branch 32 is provided with a neoprene self-sealing plug 36 through which interior cannula or catheter 38 passes in a manner hereinafter more fully described.
Referring again to Figure 2, an elongated stylet needle 40 is telescopically disposed through the entire length of the hub 12 and exterior cannula 14. The sharpened tip 42 of the needle 40 projects beyond the exterior cannula 14 so as to permit facile venipuncture and safe introduction of the exterior cannula 14 into a blood vessel according to conventional techniques. The trailing end 44 of the needle 40 is rigidly mounted within a needle hub 46. Preferably, the needle hub 46 defines a hollow interior 48 which communicates directly with the interior of the hollow needle 40. Thus, upon successful venipuncture, the needle hub 46 will reflect a blood flashback indicating successful venipuncture. -The needle is intended to pass immediately through the . .
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plug 26 in the position illustrated in Figure 2.
However, because the sleeve 24 is flexible in cvnfigu-ration, and in order to give stability to the cannula assembly 10 during venipuncture, a cylindrical housing 50 is mounted upon the needle hub 46 and telescopically circumscribes the sleeve 24 and the trailing end 22 of the hub 12. As shown best in Figure 1, the housing 50 has a plurality of keyways 52 adapted to receive a suitable detent 54. The detent 54 in cooperation with the keyway 52 locks the housing 50 temporarily in place upon the hub 12.
After venipuncture, the housing 50 may be rotated slightly about the axis of the needle 40 and retracted rearwardly as shown in Figure 3 until the needle has been removed from the exterior cannula 14. While the needle is in the advanced position illustrated in Figure 2, the throughbore 28 is substantially obstructed.
However, when the needle 40 is retracted to the position illustrated in Figure 3, at least that portion of the throughbore 28 which is forward of the intersection of bore 34 with bore 28 is unobstructed. When unobstructed, the interior catheter 38 may be advanced through the hollow of the exterior cannula 14 by digital manipulation. The catheter 38 defines a hollow passageway 56 which communicates openly with the female coupling 58. The length of catheter 38 is selected to project beyond the leading end 18 of cannula 14 when the catheter 38 is fully advanced through the bore 34. When desired, blood may be com~unicated through the passageway 56 of the interior cannula 38 by connecting a blood tubing ~o the female coupling 58. Because the catheter 38 will come in contact with the patient's blood, it may be desirable to maintain the sterility of the catheter 38. Accordingly, a suitable flexible packaging material 60 as schematically illustrated in broken lines in Figure 1 could be used. Conven-tional packaging material 60 which permits advancement of a catheter through a hub is known in the art and no further comment thereon is deemed necessary.
The method of using the catheter assembly embodi-ment of Figure 1 can best be understood by reference to Figures 3 and 4. With the needle in the fully advanced position illustrated in Figure 2, venipuncture is performed such that the exterior catheter 14 is inserted within a blood vessel to create a single fistul~.
Thereafter, the housing 50 is rotated slightly and the needle withdrawn to the position illustrated in Figure 3. Of course, if desired, the needle 40 may be com-pletely withdrawn through the plug 26, the memory of theplug 26 preventing the blood from spilling out of the hub 12. However, it may also be desirable to leave the needle in the position illustrated in Figure 3. In any event, after the needle has been withdrawn from the exterior cannula 14, the interior catheter 38 may be ~-advanced through the branch 32 until it projects a desired distance beyond the leading end 18 of the cannula 14. Thus, cannulae 14 and 38 are coextensive at least along the length of cannula 14. Notably, the ~ .,, "~ .
- .
external diameter of the catheter 38 is sufficiently less than the internal diameter of the cannula 14 that blood will flow easily therebetween. Accordingly, blood may be aspirated in the passageway between the cannula 14 and the catheter 38, through the bore 28, the hollow of the needle 40, the needle hub 46 and through extracorporeal blood circuitry (not shown) connected at 62. After the blood has traversed an extracorporeal blood circuit, it may then be returned through the coupling 58 and the passageway 56 within the interior catheter 38.
Note that blood may be withdrawn from and returned to the patient without creating an additional fistula and without otherwise modifying the structure of the catheter assembly 10. The withdrawal and return of blood may occur simultaneously or serially, as desired.
While the needle may be retained in the position illustrated in Figure 3, it has been found preferable to completely remove the needle 40 from the hub 12.
Removal is easily accommodated by withdrawing the needle from the plug 26, manually squeezing the flexible sleeve 24 to prevent outflow of blood, removing plug 26 and thereafter inserting the coupling 62 of the extracorporeal blood circuit directly into the sleeve 24. In this configuration, the risk that the needle may damage the interior catheter 28 or otherwise interfere with the flow of blood is eliminated. As pointed out in Figure 4, in this presently preferred embodiment, the interior catheter 38 may be of any desirable length and ~4~
will preferably project a substantial distance beyond the leading end 18 of the exterior catheter 14. Because the length of catheter 38 can be selected, any of a variety of distances between the leading tip 18 of cannula 14 and the leading tip of catheter 38 could be selected (see Figure 4).
Referring now to Figure 5, a modification of the embodiments of Figures 1-4 is illustrated. In Figure 5, a female Luer fitting 66 has been substituted for the rubber plug 36 as shown in Figure 2. The female Luer fitting will receive a male coupling 68 in press-fit relation to permit return of blood from the extra-corporeal blood circuit through the passageway 56 of the interior catheter 38.
In order to prevent blood within the throughbore 28 from escaping through the Luer fitting 66 as the catheter 38 is advanced, a unidirectional check ~alve 70 is provided in the branch 32. The check valve 70 is preferably made of a flexible rubber material through which the catheter 38 is easily passed in the forward direction. The valve 70 is a leaflet or duck-bill type valve.
Attention is now directed to another presently preferred cannula assembly embodiment generally desig-nated 80 and illustrated best in Figures 6-8. The cannula assembly 80 is intended to accomplish the same purpose as the assembly 10. More particularly, the assembly 80 comprises an exterior cannula 82 which is mounted at the forward end 84 of a cannula hub 86.
.
, . ' ~ ' ' ' ' , ' .
, Preferably, the exterior cannula 82 is forwardly tapered at ~8 and defines an interior bore 90 (see Figure 8).
The bore 90 of the cannula 82 communicates directly with a recess 91 in the hub 86. The recess 91 opens at the trailing end 94 of the hub 86. Rubber sleeve 87 is nested within recess 91 and defines a throughbore 92 which tightly circumscribes needle 126 to form an air-tight seal as will hereinafter be more fully described.
An interior catheter or cannula 98 traverses the entire throughbore 92 and the bore 90 of exterior cannula 82. The leading end 100 of the catheter 98 projects substantially beyond the leading end 88 of cannula 82 as shown in both Figures 7 and 8. The trailing end of catheter 98 is mounted wi~hin coupling member 102, the coupling member 102 having a male Luer fitting 104 which is in direct alignment with the throughbore 92. The interior catheter 98 is hollow and opens directly into the female Luer coupling 106. The coupling member 102 is maintained in direct alignment and fixed axial spacial relationship with the hub 86 by a strut 108. It can be seen, therefore, that there is a discrete passageway from the leading tip 100 of the catheter 98 through the entire length of the catheter 98 to the coupling member 102.
The cannula hub 86 is bifurcated at 110 to form a branch 112. The branch 112 has a female Luer fitting 114 at its trailing end 116 into which a suitable coupling 120 from a conventional extracorporeal blood circuit is press-fit. The branch 112 has a hollow interior 122 which communicates directly with the bore 90 of exterior cannula 82. Accordingly, a discrete passageway exists through the bore 90 and hollow 122 to the coupling 120. In addition, a separate and discrete passageway exists through the hollow of interior catheter 198 to the trailing end of coupling member 102 and to a male coupling 124 press-fit therein.
In order to facilitate introduction of the coex-tensive cannulae 82 and 98, a venipuncture needle 126 is provided. The venipuncture needle 126 has a sharp beveled end 128 which, in the initial position illus-trated in Figure 6, projects through the interior of cannula 82 and telescopically around and beyond catheter 98. With reference to Figure 8, it can be appreciated that the needle 126 is reciprocably displaceable within the bore 92 of the sleeve 87. The sleeve 87 forms an air-tight seal with needle 126 so that negative pressure within the hub 86 and branch 112 will not draw air around the needle 126 into the blood within the hub.
The trailing end 128 of the needle 126 is firmly mounted to a shuttle 130, the shuttle having a rearwardly facing female fitting 132 which is selectively press-fit upon the male fitting 104 of coupling member 102 as illus-trated in Figure 8. Clearly, the location of the male fitting 104 and female fitting 132 could be reversed without adverse consequence. This press-fit coupling minimizes blood leakage around the needle 126 after venipuncture and forms an air seal for preventing air from entering the hub 86 when the interior of hub 86 is subjected to negative internal pressure.
The method of using the embodiment of Figures 6-8 is apparent from the drawing. Initially, the shuttle 130 is advanced forwardly until the needle 126 projects beyond the leading end 88 of the cannula 82 and substantially circumscribes and confines the interior catheter 98. By restraining the shuttle 130 in place with the fingers, the venipuncture can easily be made.
It is observed~ however, that the needle 126 will substantially fill the passageway in the throughbore 90 between the cannula 82 and the catheter 98.
Accordingly, blood will not flow through the bore 90 and hollow 122 in the branch 112 while the needle is in the forward position illustrated in Figure 6.
After venipuncture has been successfully accom-plished and the fistula established, the shuttle 130 may be manually displaced rearwardly and telescopically over the exposed portion of the interior catheter 98 until the shuttle 130 mates with the coupling member 102. In this mode, blood will freely flow between the cannulae 82 and 98, through the branch 112 and the extracorporeal blood circuit connected at 120. At the same time, blood may also flow through the hollow of the interior catheter 98 along the discrete flow path defined by the interior catheter 98 and through the coupling 124 to the extracorporeal blood circuit.
The length of the needle 126 and the strut 108 are selected so that when the shuttle 130 is in the rearmost position illustrated in Figures 7 and 8, the sharpened leading end 128 of the needle 126 will remain supported 7~S
by the cannula hub 86 but be fully retracted out of the pathway 122 so as to avoid interfering with blood flow.
Clearly, in the embodiments illustrated herein structure and method have been described which facili-tates successful cannulation of a blood vessel and, after cannulation, the displacement and/or removal of the sharpened needle to permit essentially simultaneous aspiration of blood from the patient and delivery of blood back to the patient through two discrete flow paths in the assembly.
The invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive and the scope of the invention is, there-fore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
"
Claims (13)
1. A cannula assembly comprising in combination:
a bifurcated hub having two separate branches;
a first hollow cannula mounted in the bifurcated hub at one of said branches;
a second hollow cannula essentially coextensible with the first cannula and mounted on the hub at the other said branch;
a venipuncture needle telescopically disposed within the first said cannula and projecting therebeyond to facilitate introduction of both the first and second said cannulae into a blood vessel, said venipuncture needle being displaceable through said hub away from the blood vessel after venipuncture so as to facilitate exposure of both the first and second said cannulae within the said blood vessel; and a first flow path defined by the first said cannula and its corresponding branch of said hub and a second flow path defined by the second said cannula, the first and second flow paths being in fluid communication with extracorporeal fluid lines and being separated one from the other so that simultaneous aspiration of blood through one of the said flow paths and injection of blood through the other of the said flow paths is simultaneously accomodated.
a bifurcated hub having two separate branches;
a first hollow cannula mounted in the bifurcated hub at one of said branches;
a second hollow cannula essentially coextensible with the first cannula and mounted on the hub at the other said branch;
a venipuncture needle telescopically disposed within the first said cannula and projecting therebeyond to facilitate introduction of both the first and second said cannulae into a blood vessel, said venipuncture needle being displaceable through said hub away from the blood vessel after venipuncture so as to facilitate exposure of both the first and second said cannulae within the said blood vessel; and a first flow path defined by the first said cannula and its corresponding branch of said hub and a second flow path defined by the second said cannula, the first and second flow paths being in fluid communication with extracorporeal fluid lines and being separated one from the other so that simultaneous aspiration of blood through one of the said flow paths and injection of blood through the other of the said flow paths is simultaneously accomodated.
2. A cannula assembly as defined in claim 1, wherein the branch of said hub corresponding to said first cannula includes a flexible sleeve which may be pinched closed when the needle is withdrawn therefrom to prevent escape of fluid through said branch.
3. A cannula assembly as defined in claim 1, wherein said venipuncture needle is connected at its trailing end to a stylet needle hub which is detachable from the rigid hub so as to permit the venipuncture needle to be completely removed therefrom.
4. A cannula assembly as defined in claim 1, wherein a reciprocable member is mounted upon the trailing end of the venipuncture needle and is displaceable reciprocably between a forward position adjacent the trailing end of the rigid hub and a retracted position a fixed distance rearward of the rigid hub.
5. A cannula assembly as defined in claim 4, wherein said retracted position is defined by a coupling member axially aligned with the rigid hub and secured thereto a spaced distance from the trailing end of the hub, the member presenting a forwardly projecting male coupling onto which the reciprocating member is securable, the male coupling interiorly defining a flow path which is in open communication with the hollow of the first hollow cannula.
6. A cannula assembly as defined in claim 1, wherein said second hollow cannula is displaceable through the hollow of the first hollow cannula so that the second hollow cannula projects a significant distance beyond the forward tip of the first hollow cannula.
7. A cannula assembly as defined in claim 6, further comprising a unidirectional valve situated within the flow path through which the second hollow cannula is displaced, the valve controlling retrograde blood flow around the outside of the second hollow cannula.
8. A cannula assembly as defined in claim 1, wherein a mounting member maintains the second hollow cannula in axial alignment with the first hollow cannula, said mounting member being interiorly hollow, communicating with the hollow of the second hollow cannula and rigidly attached to the hub.
9. A cannula assembly comprising in combination:
a bifurcated cannula hub;
a first hollow cannula mounted upon the leading end of the bifurcated cannula hub and projecting forwardly thereof a first distance;
a second hollow cannula telescopically disposed within the first, the leading end of the second cannula projecting beyond the leading end of the first cannula and the trailing end of the second cannula being attached to a spaced rigid coupling member so as to be in direct axial alignment with one branch of the bifurcated cannula hub;
means for fixing the position of the spaced coupling with respect to the rigid hub;
the second branch of the bifurcated cannula hub defining a hollow flow path which flow path intersects the interior of the first hollow cannula within the rigid hub;
a venipuncture needle, the trailing end of which is secured to a reciprocating shuttle member, the leading end of the needle being reciprocably disposed within the rigid cannula hub and telescopically circumscribing the second cannula; and means accomodating displacement of the needle and shuttle from a first position in which the shuttle is in a forward position adjacent the rigid cannula hub and the needle is interposed between the first and second cannulae and projecting forward of the first cannula so as to accommodate venipuncture and a second position wherein the shuttle is rearwardly displaced into engagement with the spaced coupling thereby withdrawing the needle from within the first cannula and removing its obstructing presence from the intersecting flow path whereby blood can be simultaneously conveyed in one direction through the first hollow cannula and in the opposite direction through the second hollow cannula.
a bifurcated cannula hub;
a first hollow cannula mounted upon the leading end of the bifurcated cannula hub and projecting forwardly thereof a first distance;
a second hollow cannula telescopically disposed within the first, the leading end of the second cannula projecting beyond the leading end of the first cannula and the trailing end of the second cannula being attached to a spaced rigid coupling member so as to be in direct axial alignment with one branch of the bifurcated cannula hub;
means for fixing the position of the spaced coupling with respect to the rigid hub;
the second branch of the bifurcated cannula hub defining a hollow flow path which flow path intersects the interior of the first hollow cannula within the rigid hub;
a venipuncture needle, the trailing end of which is secured to a reciprocating shuttle member, the leading end of the needle being reciprocably disposed within the rigid cannula hub and telescopically circumscribing the second cannula; and means accomodating displacement of the needle and shuttle from a first position in which the shuttle is in a forward position adjacent the rigid cannula hub and the needle is interposed between the first and second cannulae and projecting forward of the first cannula so as to accommodate venipuncture and a second position wherein the shuttle is rearwardly displaced into engagement with the spaced coupling thereby withdrawing the needle from within the first cannula and removing its obstructing presence from the intersecting flow path whereby blood can be simultaneously conveyed in one direction through the first hollow cannula and in the opposite direction through the second hollow cannula.
10. A cannula assembly as defined in claim 9, further comprising means forming an air-seal between the needle and the cannula hub to minimize air influx into the hub when the hub is subjected to negative pressure.
11. A cannula assembly comprising in combination:
a hub having a forward end and a trailing end and a bore axially disposed therethrough, said hub further comprising at least one angularly related branch, said branch also having a bore therethrough, the trailing end of the hub comprising a coupling site;
an exterior cannula mounted upon the hub and communicating with the hollow of both the hub and the branch;
an elongated needle normally telescopically disposed through the hub and exterior cannula and projecting therebeyond to facilitate venipuncture, the needle being axially displaceable out of the exterior cannula;
an interior cannula situated within the angularly related branch such that the leading tip is normally spaced from the needle when the needle is telescopically disposed within the exterior cannula, the interior cannula being axially displaceable along the branch and telescopically through the interior of the exterior cannula when the venipuncture needle has been rearwardly displaced; and the external diametral dimension of the interior cannula being sufficiently less than the internal diametral dimension of the exterior cannula that blood can be simultaneously transferred in one direction through the exterior cannula and needle hub and in the other direction through the interior cannula and the branch.
a hub having a forward end and a trailing end and a bore axially disposed therethrough, said hub further comprising at least one angularly related branch, said branch also having a bore therethrough, the trailing end of the hub comprising a coupling site;
an exterior cannula mounted upon the hub and communicating with the hollow of both the hub and the branch;
an elongated needle normally telescopically disposed through the hub and exterior cannula and projecting therebeyond to facilitate venipuncture, the needle being axially displaceable out of the exterior cannula;
an interior cannula situated within the angularly related branch such that the leading tip is normally spaced from the needle when the needle is telescopically disposed within the exterior cannula, the interior cannula being axially displaceable along the branch and telescopically through the interior of the exterior cannula when the venipuncture needle has been rearwardly displaced; and the external diametral dimension of the interior cannula being sufficiently less than the internal diametral dimension of the exterior cannula that blood can be simultaneously transferred in one direction through the exterior cannula and needle hub and in the other direction through the interior cannula and the branch.
12. A method of introducing a double lumen cannula into the cardiovascular system of a patient comprising the steps of:
interposing a stylet needle within the hollow of a first cannula;
introducing the first cannula into the cardiovascular system;
displacing the needle away from the first cannula such that a blood flow path is defined between the first cannula and a first coupling member in communication therewith;
introducing a second cannula through the hollow of the first cannula, the second cannula defining a blood flow path from the tip of the second cannula to a second coupling mounted upon the trailing end of the second cannula; and projecting the leading end of the second cannula beyond the leading end of the first cannula such that two separate and distinct flow paths are created through the first and second cannulae.
interposing a stylet needle within the hollow of a first cannula;
introducing the first cannula into the cardiovascular system;
displacing the needle away from the first cannula such that a blood flow path is defined between the first cannula and a first coupling member in communication therewith;
introducing a second cannula through the hollow of the first cannula, the second cannula defining a blood flow path from the tip of the second cannula to a second coupling mounted upon the trailing end of the second cannula; and projecting the leading end of the second cannula beyond the leading end of the first cannula such that two separate and distinct flow paths are created through the first and second cannulae.
13. A method of introducing a double lumen cannula into the cardiovascular system of a patient comprising the steps of:
interposing a stylet needle through the hollow of a first cannula, the stylet needle being interiorly hollow;
mounting a second smaller diameter cannula telescopically within the hollow of the stylet needle and so as to project beyond the leading end of the first cannula;
simultaneously introducing both the first and second cannulae into the cardiovascular system of a patient;
displacing the stylet needle away from the leading ends of the first and second cannulae; and aspirating blood from the cardiovascular system through one of the cannula and returning blood to the cardiovascular system through the other of the cannula.
interposing a stylet needle through the hollow of a first cannula, the stylet needle being interiorly hollow;
mounting a second smaller diameter cannula telescopically within the hollow of the stylet needle and so as to project beyond the leading end of the first cannula;
simultaneously introducing both the first and second cannulae into the cardiovascular system of a patient;
displacing the stylet needle away from the leading ends of the first and second cannulae; and aspirating blood from the cardiovascular system through one of the cannula and returning blood to the cardiovascular system through the other of the cannula.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US82184877A | 1977-08-04 | 1977-08-04 | |
| US821,848 | 1977-08-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1114705A true CA1114705A (en) | 1981-12-22 |
Family
ID=25234450
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA307,492A Expired CA1114705A (en) | 1977-08-04 | 1978-07-17 | Cannula and method for bidirectional blood flow |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0000831B1 (en) |
| JP (1) | JPS5428499A (en) |
| CA (1) | CA1114705A (en) |
| DE (1) | DE2862201D1 (en) |
| IT (1) | IT1097699B (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5645106A (en) * | 1979-09-18 | 1981-04-24 | Yanmar Agricult Equip | Automatic steering device of transplanter |
| DE3010841A1 (en) * | 1980-03-21 | 1981-10-08 | Ulrich Dr.med. 6936 Haag Uthmann | CATHEDER |
| NO811917L (en) * | 1980-06-10 | 1981-12-11 | Wallace Ltd H G | INTRAVASCULAR DEVICE. |
| DE3112762A1 (en) * | 1981-03-31 | 1983-01-13 | Jürgen Dr.med. 8700 Würzburg Schrezenmeir | Double-lumen blood sampling, single-lumen infusion, subclavian catheter set |
| JPS5889052U (en) * | 1981-12-10 | 1983-06-16 | テルモ株式会社 | intravascular indwelling needle |
| GB2137500B (en) * | 1983-03-22 | 1986-10-08 | Miles Allison | Cannula |
| JPS61106256U (en) * | 1984-12-16 | 1986-07-05 | ||
| FR2689402B1 (en) * | 1992-04-03 | 1997-07-04 | Farcot Jean Christian | PERCUTANE VASCULAR INTRODUCER FOR SUPPLYING AN EXTRACORPOREAL BLOOD CIRCUIT. |
| US5421825A (en) * | 1993-10-06 | 1995-06-06 | Farcot; Jean-Christian | Percutaneous vascular introduction device for the feeding of an extracorporeal blood circuit |
| DE69523887T2 (en) * | 1994-08-25 | 2002-08-29 | Baxter Int | CLOSED BLOOD SAMPLING DEVICE |
| DE19729022C2 (en) * | 1997-07-08 | 1999-07-22 | Josef Magasi | Double lumen cannula |
| WO2006022025A1 (en) * | 2004-08-26 | 2006-03-02 | Kobayashi, Hideki | Medical instrument |
| DE102017000940A1 (en) | 2017-02-02 | 2018-08-02 | Xenios Ag | Arrangement with a blood pump, a control unit and a device for transmitting the measured values |
| US20210178142A1 (en) * | 2019-12-13 | 2021-06-17 | Lsi Solutions, Inc. | Adjustable cannulation assembly and methods thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5236358B2 (en) * | 1973-08-09 | 1977-09-14 | ||
| US4016879A (en) * | 1973-08-22 | 1977-04-12 | Dynasciences Corporation | Multi-mode cannulating apparatus |
| US3875938A (en) * | 1973-08-22 | 1975-04-08 | Eli K Mellor | Multi-mode cannulating apparatus |
| US4096860A (en) * | 1975-10-08 | 1978-06-27 | Mclaughlin William F | Dual flow encatheter |
| US4073297A (en) * | 1976-02-11 | 1978-02-14 | Sandoz Ltd. | Catheter |
| LU77252A1 (en) * | 1976-05-06 | 1977-08-22 |
-
1978
- 1978-07-17 CA CA307,492A patent/CA1114705A/en not_active Expired
- 1978-07-28 JP JP9167478A patent/JPS5428499A/en active Pending
- 1978-08-03 EP EP78300235A patent/EP0000831B1/en not_active Expired
- 1978-08-03 DE DE7878300235T patent/DE2862201D1/en not_active Expired
- 1978-08-04 IT IT26467/78A patent/IT1097699B/en active
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5428499A (en) | 1979-03-03 |
| EP0000831B1 (en) | 1983-03-16 |
| IT7826467A0 (en) | 1978-08-04 |
| DE2862201D1 (en) | 1983-04-21 |
| EP0000831A1 (en) | 1979-02-21 |
| IT1097699B (en) | 1985-08-31 |
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| Date | Code | Title | Description |
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| MKEX | Expiry |