CA1064357A

CA1064357A - Catheter placement assembly

Info

Publication number: CA1064357A
Application number: CA249,159A
Authority: CA
Inventors: Richard H. Mcfarlane
Original assignee: TAUT
Current assignee: TAUT
Priority date: 1975-09-18
Filing date: 1976-03-30
Publication date: 1979-10-16
Also published as: FR2353306A1; DE2615702A1; BE843880A; DE2615702B2; US4046144A; DE2615702C3; MX143009A

Abstract

CATHETER PLACEMENT ASSEMBLY

Abstract of the Disclosure An improved catheter placement assembly which includes an improved rigid needle and hub assembly and an improved catheter assembly with a flexible cannula jacketing the needle shank and a flexible body of rubbery material on its proximal end with a rigid adapter to connect to an I.V. set the hub of the needle defines a chamber to protectively house the adapter connection zone during venipuncture.

Description

This invention relates to an improved catheter placement assembly, and, more particularly, to an improved needle construction and to an improved catheter structure and combination of the same in the placement assembly.
In the past, there have been numerous types of catheters which are flexible and which are provided with rigid adapters on one end to connect to a medical device, for example, a tubing for intravenous feeding, etc., after a rigid needle or stylet has been removed from within it following a venipuncture operation.
This invention relates to an improved catheter comprising: a hollow, rigid, elongate needle with a pointed distal end and a proximal end zone, and a hub of rigid plastic material with a central zone secured about the proximal end zone of the needle, said central hub zone having a distally-extending generally cylindrical shroud spaced from said needle defining an annular, distally opening axially extending chamber, and said central hub zone having a proximally extending tubular wall defining a proximally opening flash chamber, the proximal end zone of said needle being in open communication with said flash chamber, and a vented removable cap closing said flash chamber.
The present invention in one form is of an improved catheter and needle assembly which includes a catheter having a generally tubular body or housing intermediate the adapter and catheter proper which is formed of a flexible and bendable rubbery material. Among the improvements is structure within the lumen of the tubular body or housing which projects into the lumen or passageway so that upon bending, flexing or external application of pressure, the lumen through the body or housing is not completely occluded -and flow is not completely blocked.
The present invention also includes structure which accomplishes the following objects:
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It is also an object of this invention to provide an improved catheter placement assembly which includes a needle with a hub fixed to the proximal end zone which : includes a distally-extending axially-opening hood or skirt to define an annular chamber to protectively house the mouth or luer of the adapter to avoid contamination of it by removing the fingers from the luer's edge or lip while the placement assembly is manipulated during a venipuncture operation.
It is another object of ~his invention to provide an improved catheter which includes a housing or generally :~ tubular body on the proximal end of the catheter which is of ruWery material so that it may be easily manipulated and which is of a sufficient axial length to provide adequate handling room to advance the catheter along the needle while the catheter is being inserted to avoid contamination of the luer edge or lip as it is withdrawn from the protective .- housing within the skirtof the needle hub.
It is another object of this invention to provide an improved housing between the catheter proper and the adapter so that the proximal end of the catheter housing can be easily manipulated to orient the adapter to a favorable angle for connection to a tubing of an intravenous set, for example, Pigure 2.
It is another object of this invention to provide an improved catheter and needle assembly which includes a

- 2 -flash back chamber so that upon introduction of the needle into a vein there will be a flow of blood into the chamber and the therapist can visually observe that the tip of the needle is in the correct position within a vein.
It is also an object of this invention to provide an improved device which includes a vent means to permit air, but not blood, to escape from the flash back chamber in response to blood pressure on venipuncture; thus, the pressure does not build up and stop blood flow into the chamber.
It is a further object of this invention to provide an improved catheter with radially outwardly projecting surfaces on the housing which are sized and positioned to adapt it to be readily taped in position and which stabilize the unit once in position.
It is also an object of this invention to provide a catheter with an improved housing of a soft rubbery material which is adapted to be manipulated without closing the flow path through it and yet which can be manipulated to reduce the amount of blood flow through it without permitting an accidental occlusion.
It is a further object of this invention to provide a catheter which has a flexible body or housing at the proximal end which is of bendable or rubbery material so that it is not only comfortable but can be easily bowed away from the skin surface to provide clearance for manipulating it to connect to tubes, etc., as is often re~uired.
It is also an object of this invention to provide a catheter placement assembly which includes a flexible catheter sheathing a needle, which catheter includes a tubular body or housing at its proximal end, which housing is of : a first axial length and with an adapter on the proximal end to connect to a medical device, and which needle includes a hub with an axially-facing, distally-opening skirt defining an annular chamber of a depth of a second predetermined length which is less than that of the first axial length and which is sized companionately to the adapter to protectively house the end thereof within the skirt during venipuncture so that it is not contaminated.
In accordance with these and other objects which will become apparent from the following description is of a preferred embodiment of the invention which is shown in -~
a suitable size in Figure 3.
Figure 1 is a partial view illustrating the catheter ; inserted and in use with a cap closing the end of the luer;
Figure 2 is a view similar to Figure 1 and illus-trating the flexible rubbery body uf the housing of the catheter;
Figure 3 is an exploded view which is partly in cross section to illustrate the arrangement of the parts of the improved catheter assembly;
Figure 4 is a view in cross section taken on the longitudinal centerline of the improved catheter in an assembled condition;

Figure 5 is a view in cross section taken along the plane indicated by the line 5-5 of Figure 3 and looking in the direction of the arrows; and Figure 6 is a view in cross section of an alter-native embodiment of the invention and illustrating the needle and housing connection in an alternative form to that shown in - the central zone of Pigure 4.
Referring to the drawings, wherein like reference characters designate like or corresponding parts throughout ~ -the several views, and referring particularly to Figure 4, : there is shown what is often termed in the art a catheter placement assembly. It is composed of two main portions:
a) a needle and hub assembly 12 and b) a catheter or cannula ` assembly 16.
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~; Generally speaking, the needle and hub assembly 12 comprises a hollow elongate pointed needle 15 with a hub '~. 18 fixed to the proximal end, and which is structured to f~ define a proximally located flash chamber or blood reservoir 20. The cannula assembly 16 comprises a tubular elongate, ' 2Q flexible needle cannula, catheter or sheath 22 sized to . ....... . .

receive and ~acket the main length of the needle 15 and a proximally l~cated yieldable body or housing 24 of ` rubbery material on it which in turn is provided with an `1 annular adapter 25 on the end which is sized to nest . ' .
;I removably within a protective .~ood extending axially from the needle hub when the two main portions are assembled as a catheter placement assembly.

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Referring in more detail to the first main portion, the needle and hub assembly 12, it comprises a conventional, hollow, distally-pointed, elongate needle or rigid stylet 15 connected to a hub 18 by conventional means. The means to connect may include a tubular fitting 22 fixed to the proximal end zone 24 of the needle with a first end 26 and a second end 28 which are radially out-turned or upset to engage shoulders formed in the central zone of the hub to captivate `
the needle against axial movement of withdrawal or separation of it from a central axial bore through the hub 18.
The body of the hub includes the central zone 30 with the aforementioned through bore and a distally and axially extending hood or skirt 32 spaced from the needle shank defining an axially-opening annular receptacle 34.
The hub body also includes a proximally-extending tapered, i.e., generally truncated conical, wall 36 defining an internal flash chamber 38 which terminates in an open mouth 40 that is closed by a removable cap means 42. The forward or distal end of the skirt 32 is provided with an out-turned rim means 44 to facilitate axial movement of the catheter plscement assembly during venipuncture; and the exterior surface of this skirt may include gripping means in the form of radially-extending fins 46. The rear cap means 42, which closes the end of the flash chamber, is provided with tapered walls which correspond with the taper of the wall 106435~ " `
36. The exterior surfaces of the end cap may also be rovided with grip means a~ at 48 to rotatingly manipulate the same.
The fla~h chamber is preferably vented by suitable vent means. In the preferred embodimant a filter disk 50 is secured by suitable means in spanning relation of an opening through the end 5~ of the cap. In a preferred embodiment, the filter disk is of bacteriological filter mato~ial through which air may pass, but the blood components aannot readily pass. Thus a ~isk may be conveniently made with the commercially available material known as, TYVER, a trademark of the duPont Company; it consist~ of a thin sheet of polyethylene fibers in mat form which material has the quality of allowing air to escape but not blood. In a preferred embodiment, the disk 50 is suitably secuxed in spanning relation of the open ended cap and may be bonded to the material of the end cap by heat means to fuse the margin o the disk to the wall of the end cap about the opening~ In the preferxed embodiment ~he exterior of the end cap i~ provided with a radial flange 51 or rim to serve as a gripping means for removal of the end cap to connect to another medical device, the wall 36 ~erving as a fitting or connector means.
The cannula assembly 16 includes a flexible catheter sl~eathing the n-~dl-, such as a leng~h of reflon~ s trademark - ... . .... :........... . .. . - .. - ~ - . -of the duPont Company, to completely jacket or sheath a companionately sized needle from the flexible housing to the eveled needle point proper. Preferably the catheter end 53 is feathered or tapered to the needle surface at the proximal zone of the needle point proper for ease in entering on venipunc~ure. The venipuncture is produced by the needle, which i8 removably shea~hed within the catheter and which has a sharp, tapered, penetrating tip projecting in advance of the leading end or feathered end ~f the c~theter. In the preferred embodiment, the proximal end zone of the cannula or;catheter tube i~ secured to the hou~ing which is of yieldable or rubbery ma~erial. Retention meanB 54 interconnect the proximal end of the catheter in fluid communication with the interior of the housing to which it is fixed. The retention means may comprise a short, tubular ~egment or hinge joint of ri~id, plastic material ~. .
~ telescoped ov~r the end of the cannula and bonded to or ,, vulcanized to the rubbexy material of the housing. The segment is fixed to the end zone of the catheter as by a tight fit, 30~ Fig. 4. Alternatively, as in Fig. 6, where, 1 ~ for example, the catheter or cannula is of Teflon, the retention means 54' may comprise a tubular segment with the proximal end 61 of the Teflon~passed through it and 1 turn~d back on it~elf as at 64 over the end zone 63 to form - a machanical lock against axial movement ~upplemented by r~a/c ~rk ~; ~

106435~ -a bond between the rubbery material which is in effect vulcanized to the rigid plastic segment. To the proximal end of the rubbery housing, the adapter is connected. The ; exterior of the adapter is sized and is receivable and nest~ble snugly, yet removably, within the skirt of the hub. The skirt is preferably interiorly tapered to seat a rigid rim 69 and to limit axial movement of the rim 69 into the s~irt thus serving as stop means for the catheter and ~ans to orient the feathered end at the needle tip zone.
Preferably~ the rim 69 is square as seen in cross section and viewed axially. Within the longitudinally-extending bore of the housing, as shown in Fig. 5, longitudinally-extending ribs are provided which prevent occlusion of the longitudinally-extending pa~sageway when the housing is flexed .~
as shown in Figure 2 or when ex~ernal pressure i8 applied to the housing.
The overall sizing of a preferred embodiment is as shown ~n Figur2 3 of the drawing, which i~ to size. This size provides a relatively large flash chamber of about ~: .
one-elghth inch in diameter and of about one inch in axial length so that visual observation can be made readily of blood in the flash chamber through the translucent wall to signal that the tip i8 properly in the vein. In the preferred embodiment, the hub of the needle and the adapter and the re~ntion means are of molded plastic in the rigid range, for example, polypropylene. The rubbery material ,~ ,' _g_ ,~;

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The rubbery material should be such that, as shown in Fig. 2, flexing of the cannula housing is possible for manipulating it for most favorable orientation of the adapter end or `` luer to facilitate connection to tubing or another medical device. Because it i5 relatively soft it is comfortable when in place for long periods of time. The ru~bery material of the body or housing of the preferred embodiment is bonded or vulcanized by heat to the adapter and to the retention means, the latter being effective to lock the cannula to the body as explained above for po~itive connection.
Pref~rably the adapter is provided with a distalmost annular and symmetrical, axial nose 72 which projeats into the through bore of th~ housing as ~hown. Further, ~tabilizing wings or ears 73 and 75 are provided on the exterior surface of the distal end of the cannula housing to provide stability again~t xolling and provide means for connecting the cannula by tape to the body of a patient when properly positioned.
A woakened zone as shown at the tip of the arrow 75 may be provided in ea~h ear to anchor it in place by sutures.
Praferably, an elongate protector shroud 81 of rigid plastlc is provided which is closed at one end 83 and is open at the other Qnd 85 and is sized ~o receive the rim of th~ hub of the needle to suspend it in protective relation within the elongate shroud prior to use. The wall of the shroud adjacent T~aJe ~rk -10- , .
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- ~064357 ~ , the open end 85 is inwardly tapered desirably and it includes a shoulder which abut3 the rim 44 when assembled which serves as a stop means to limit penetration of the needle into the protector shroud.
For use, the protector i~ first removed from the catheter and needle asse~bly. The venipuncture operation is performed in the usual manner. The hub which i~ of sufficient axial length to manipulate it conveniently is grasped about the skirt which protectively houses the end or rim 69 of the catheter adapter about the opening. When the vein has been punc~ured, blood will flow through the hollow needle and into the flashback chamber. Then, by handling the exposed portion of the flexible catheter body, see the zone indicated by the numeral 24, the catheter i~ advanced until it reaches the desired po~ition in the vein, while the needle a~sembly i~ h~ld in a relatively fixed p~ition by continuing to grasp the hub. It will be seen that the fingers do not contaminate the proximal opening of the adapter in 80 doing. After thi~
has been accomplished, the needle is completely r2moved.
The end of a tube of an I.V. set i8 then connected to the rim ., .
of the adapter of the catheter. Finally, using a sling type taping, the catheter i9 anchored into position or otherwise anchored in place.
As shown in Figure 3, the axial length of the rubbery material of the tubular catheter body or housing is gr~a~er ''!`. than one-half inch and is pre~erably not longer than one ..

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inch, while, as seen in ~ross section, it has an outside diameter of about one-quarter of an inch between the center and proximal end and is provided with a through bore of about one-eighth of an inch so as to have a subs~antial mass and resistance to buckeling in response to axial force application.
Preferably, the stabilizing wings are of the same rubbery material as the cathet~r body. The ca~heter body or housing comprises a readily bowable or bendable member while the tubular ratention means 54 and 54', whi~h i8 rigid, serves as a hinge means element between the relatively flexible , ~ material of the cannula and the bendable body. The axial . . .
; depth of the chamber in the skirt of the needle hub, between its open mouth and the stop means, determines the prote~ted location of the opening into the adapter on the proximal end of the catheter; preferably this is at least one-quarter inch and between one-quarter in~h and one-half inch. The axial length o~ the gripping area of the skirt, that is, ;~ between the rim and the flash chamber, iq about one-half inch i and between one-quarter and three-quarters o an inch.
It is ~hus ~een that the devico provides a protective annular chamber within the skirt of the needl~ hub which protectively house~ the proximal end or mouth of the cannula ` during the venipuncture operation; and that the exterior of the ~kirt may be grippsd to hold the needle in position while the cannula i~ advanced by gripping the portion of the flexible rubbery body extending from the mouth of the skirt .

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106~357 and advancing the catheter in the vein relative to the needle point for proper positioning. When the needle is removed, the end of the catheter assembly can be bowed upwardly as shown in Figure 2 for connection to another medical device, . such as a tube, for intravenous feeding.

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Claims

The embodiment of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An improved catheter comprising:
a hollow, rigid, elongate needle with a pointed distal end and a proximal end zone, and a hub of rigid plastic material with a central zone secured about the proximal end zone of the needle, said central hub zone having a distally-extending generally cylindrical shroud spaced from said needle defining an annular, distally opening axially extending chamber, and said central hub zone having a proximally extending tubular wall defining a proximally opening flash chamber, the proximal end zone of said needle being in open communica-tion with said flash chamber, and a vented removable cap closing said flash chamber.

2. The device as set forth in claim 1 wherein the distally opening mouth of said hub is provided with rim means radially extending outwardly to facilitate axial movement of the needle in a distal direction.

3. The device as set forth in claim 1 wherein the exterior surface of the wall includes gripping means.

4. The device as set forth in claim 1 wherein said cap means comprising a cup-shaped member and means to connect the cap means to the proximal end zone of the wall about said flash chamber comprising matching tapered surfaces.

5. The device as set forth in claim 1 wherein the cap means has an opening and includes a piece of bacterial filter material which is porous to air and non-porous to liquids fixed in spanning relation of said opening.

6. The improved catheter as set forth in claim 1 including a thin flexible elongate jacket having a proximal end and a distal end snugly jacketing the needle from the zone of the pointed distal end along the intermediate length of the needle and a rigid adapter fixedly connected to the jacket sized for snug receipt within said shroud protectively within said chamber.

7. The improved catheter as set forth in claim 6 wherein a protector member is provided having a closed elongate cup-shaped receptacle to receive the needle and means to connect the member to the needle hub.

8. The device as set forth in claim 6 wherein said catheter comprises a generally tubular body of rubbery material of a predetermined axial length fixed at one end to said adapter and the other end to said jacket.

9. The device as set forth in claim 8 wherein said jacket is provided with a rigid tubular segment of plastic telescoped over the proximal end zone of the jacket and means connecting the tubular segment to the tubular body.

10. The device as set forth in claim 8 wherein the oppositely extending ears of a substantially common size are provided on the tubular body at the said other end to stabilize the body and said body being adapted to be bowed intermediate its length by lifting its said one end.

11. The device as set forth in claim 5 wherein said material is of a thin sheet of polyethylene fibers in mat form.

12. The device as set forth in claim 5 wherein the material is TYVEK, a trademark of a commercially available product of the E.I. duPont de Nemours Co.

13. The device as set forth in claim 11 wherein the material is in sheet form and the margin of the filter material is fused to the cap means, and said cap means is of rigid plastic material.

14. The device as set forth in claim 6 wherein the proximal end of the rigid adapter is within said chamber a distance of at least one-quarter of an inch.

15. The device as set forth in claim 7 wherein the cup-shaped member is sized to receive the distal end of said shroud and includes stop means to limit insertion of said hub into said cup-shaped member.

16. The device as set forth in claim 8 wherein the axial length of said tubular body of rubbery material is greater than one-half inch.

17. The device as set forth in claim 16 wherein the diameter of said rubbery material is about one-fourth of an inch at the proximal end.