Fluid Infusion

Abstract

A novel fluid infusion assembly and method, the assembly comprising a stylet catheter and associated novel guide core which carries a surmounting self-sealing penetrable jacket accommodating placement of a stylet needle within the catheter prior to venipuncture and removal of the stylet needle subsequent to venipuncture while a fluid delivery tube is continuously communicating fluid to the catheter. An improved fluid coupling is adapted to penetrate the jacket and guide core at selected locations to provide an alternate site for delivering fluid to the catheter or for delivering a plurality of fluids to the catheter simultaneously. The stylet needle has, at the curved terminal end thereof, an upstanding tab which novelly accommodates (1) aspiration of blood from the vein to a transparent portion of the tab, or (2) outflow of blood from the vein to a transparent portion of the tab by normal blood pressure and capillary action to evince a successful venipuncture. The method includes squeezing the tab prior to and during venipuncture and thereafter aspirating blood into the tab and also removing the stylet needle and penetrating the self-sealing jacket with a fluid connector.

Description

The present invention comprises a novel fluid infusion assembly and method and more particularly an improved guide core and peripheral sealing jacket for selective attachment of an improved fluid coupling and selective insertion and withdrawal of a unique stylet needle in a catheter.

Known stylet catheters principally comprise a linearly shaped needle or stylet disposed within a catheter and connected at the trailing end thereof to a plug which seals the trailing end of the catheter during venipuncture. Subsequent to venipuncture, when it is desired to pass fluid through the catheter into the vein, the plug and attached needle must be removed to accommodate connection of the fluid delivery tube to the catheter. During the time increment after the needle has been removed and before the delivery tube has been attached to the catheter, it is likely that blood will flow through the catheter to the exterior thereof undesirably causing blood staining of clothing or other adjacent material and occasionally requiring a substantial cleanup process such as complete change of bedding. Moreover, during the connection of the delivery tube to the catheter, there is a substantial chance that air may be introduced into the catheter tube which increases the likelihood that a dangerous embolism will be developed within the punctured vein. Moreover, prior to the invention of the novel fluid assembly by the Applicant, it was difficult if not impossible to accommodate infusion of more than one fluid through the same catheter simultaneously.

It is, therefore, a primary object of the present invention to overcome or alleviate problems of the mentioned type.

The presently preferred embodiment of the invention comprises a stylet catheter associated with a novel guide core having a penetrable self-sealing sleeve or jacket disposed thereon. When the guide core is disposed directly adjacent the catheter, an axial slot is disposed therein so that the linear end of a unique needle may penetrate the self-sealing jacket and be inserted through the interior of the catheter. The trailing end of the needle is curved so as to be disposed exterior of the guide core when the stylet needle is carried within the catheter. The trailing end of the needle is integrally attached to an upstanding tab which provides for "flash-back" of blood when a successful venipuncture is performed. If desired, the guide core may be disposed intermediate of a fluid delivery tube as well as adjacent the intravenous catheter and, in either event, may be provided with a transverse aperture accommodating penetration by an improved fluid coupling to accommodate simultaneous infusion of more than one fluid at a time.

It is, therefore, another primary object of the present invention to provide a novel infusion assembly and methods which provide for removal of the stylet needle and fluid delivery through a catheter without interchange of coupling parts.

Another important object of the present invention is to provide an improved method and assembly accommodating simultaneous infusion of a plurality of fluids.

Another and no less important object of the present invention is the provision for a unique stylet needle accommodating aspiration of blood into a transparent reservoir which is unobstructed from view when the stylet needle is disposed within the catheter to demonstrate completion of a successful venipuncture.

One still further object of the present invention includes a novel guide core and jacket combination including a novel method providing for safe, efficient penetration and removal of needles or couplings with negligible loss of blood.

Another and no less important object of the present invention is the provision of an improved needle-guide core combination accommodating selective infusion of fluid through the stylet needle.

One further object is to provide a unique finger tab comprising part of the stylet needle.

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 following drawings wherein:

FIG. 1 illustrates in perspective one presently preferred infusion assembly embodiment of the invention;

FIG. 2 is an exploded perspective view of the infusion assembly illustrating the several component parts thereof;

FIG. 3 is a longitudinal cross section taken along lines 3--3 of FIG. 1;

FIG. 4 is a longitudinal cross-sectional view taken along lines 4--4 of FIG. 1;

FIG. 5 is an enlarged cross-sectional elevation illustrating the internal relationship of the catheter attachment and adjacent parts of the embodiment of FIGS. 1 and 2;

FIG. 6 is a cross-sectional enlarged elevation of one presently preferred tab embodiment;

FIG. 7 is a fragmentary cross section illustrating one embodiment of the improved needle as it is disposed within the guide core;

FIG. 8 is a fragmentary cross section of another improved needle disposed within the guide core;

FIG. 9 illustrates in perspective another presently preferred embodiment of the outer self-sealing jacket;

FIG. 10 is a longitudinal cross section taken along lines 10--10 of FIG. 9;

FIG. 11 is a transverse cross section taken along lines 11--11 of FIG. 9;

FIG. 12 is a fragmentary perspective illustrating another presently preferred infusion assembly embodiment;

FIG. 13 is an exploded perspective view of the infusion assembly of FIG. 12 illustrating the respective component parts thereof;

FIG. 14 illustrates in fragmentary perspective the embodiment of FIG. 12 with the needle removed and with a fluid coupling connected therein;

FIG. 15 is a longitudinal cross section taken along lines 15--15 of FIG. 14; 25, and is provided with a planar surface 262 at the proximal end thereof for abutment by the distal end of the self-sealing

FIG. 16 is a transverse cross section taken along lines 16--16 of FIG. 14;

FIG. 17 illustrates in perspective one presently preferred embodiment of a fluid coupling which may be used with the infusion assembly of FIG. 12;

FIG. 18 is a side elevational view of another preferred embodiment of the infusion assembly with parts broken away to reveal internal parts thereof;

FIG. 19 is a schematic fragmentary perspective illustrating an intermediate guide core and surmounting jacket used with the infusion assembly of FIG. 12;

FIG. 20 is a transverse cross-sectional view taken along lines 20--20 of FIG. 19;

FIG. 21 is a longitudinal cross section taken along lines 21--21 of FIG. 19;

FIG. 22 is a top plan view of an auxiliary tube accommodating the coupling of FIG. 17, parts being broken away to reveal the internal structure thereof;

FIG. 23 is a fragmentary perspective illustrating a further presently preferred infusion assembly embodiment;

FIG. 24 is an exploded perspective view of the infusion assembly of FIG. 23 illustrating the respective component parts thereof; and

FIG. 25 is a longitudinal cross section of the embodiment of FIG. 23 taken on the line 25--25 thereof.

Reference is now made in detail to FIGS. 1 and 2 which depict one embodiment of the infusion assembly generally designated 30, which broadly comprises a needle sheath 32, a catheter 42, an outer sleeve 48, an inner jacket 58, an inner guide core 60, and a stylet needle 86.

The catheter tube 42 is preferably formed of a suitable transparent or translucent radiopaque synthetic resin, such as polyvinyl, polypropylene, polyethylene, polytetrafluoroethylene, etc. The catheter 42 is centrally hollow and integrally attached at the proximal end 43 thereof to the forwardly tapered projection 44 comprising the distal end of an outer sleeve 48. The tapered projection 44 is adapted to be press-fit into the central bore 37 of a conventional needle sheath 32. The needle sheath 32 is provided with an annular collar 34 having a planar face 38 at the proximal end thereof, the collar 34 having axial ribs 36 providing a non-slip finger-gripping surface for removing the needle sheath from the outer sleeve when desired. The distal end 40 of the sheath 32 may be either opened to the air or obstructed with a cotton plug or the like as is conventional. The needle sheath 32 is sufficinetly long to entirely enclose the catheter 42 when in the assembled position as illustrated in FIG. 1.

The outer sleeve 48 comprises a central bore 56 which terminates in a bore 57 having a reduced diametral dimension (FIG. 5). The bore 57 is provided with a series of annular steps 46 which gradually decrease in diametral dimension from the proximal end adjacent the bore 56 to the distal end adjacent the bore 57. The steps 46 are contiguous with the mating end 47 of the catheter 42 and are preferably secured thereto with a suitable bonding agent such as epoxy (not shown). Thus, the catheter 42 is immovably secured to the outer sleeve 48.

The outer sleeve 48 is further provided with an axially disposed slot 50 which opens outwardly at the proximal end 54 thereof and terminates at 52 adjacent the axial midpoint of the outer sleeve 48. The purpose for the slot 50 will be subsequently more fully described.

An inner guide core generally designated 60 is provided with a forwardly tapering male fitting 62 at the distal end thereof and an integrally connected peripherally enlarged forward flange 64. The flange 64 and a rearwardly located flange 72 cooperate to define an intermediate portion 74 having a reduced diametral dimension. The flange 72 is an integral part of a diametrally enlarged coupling socket 76. An axial bore 78 is disposed throughout the entire length of the inner core 60 and is adapted to be disposed coaxially with the hollow of catheter 42 in the assembled position. In the assembled position, as illustrated in FIG. 5, the forwardly tapered male fittng 62 is press-fit into the enlarged portion 47 of the catheter 42 in the vicinity of the projection 44.

As shown in FIG. 2, the inner guide core 60 is provided with an axial slot 66 having a distal end 68 terminating immediately rearward of the peripheral flange 64 and a proximal end 70 terminating immediately forward of the flange 72. In the assembled relation, slot 66 is preferably in alignment with slot 50 in the outer sleeve 44.

The resilient, penetrable, self-sealing jacket 58 is carried by the reduced diametral portion 74 of the core 60 between the flanges 72 and 64. The jacket 58 is preferably formed of latex rubber or similar self-sealing material and, when suitably superimposed upon the intermediate portion 74 of the guide core 60, forms a substantial fluid seal therewith particularly around the periphery of slot 66. The jacket 58 is telescopically disposed within the outer sleeve 48 subsequent to its placement upon the inner core 60 as best illustrated in FIGS. 3-5.

If desired, a plug 82 having a forwardly tapered male fitting 80 may be press-fit within the coupling socket 76 to prevent inadvertent flow of blood out of the coupling socket subsequent to venipuncture. The male fitting 80 is provided with axially disposed raised portions (not shown) as is conventional with standard luer fittings and the coupling socket 76 preferably comprises luer dogs (not shown) so that the fitting 80 and the coupling socket 76 cooperate to form a standard LUER-lok assembly. Also, the plug 82 is provided with axially disposed ribs 84 which facilitate manipulation and removal of the plug 82 from the socket 76 when desired. Clearly, a fluid delivery tube, such as tube 210 (FIG. 19) may be coupled into the guide core 60 in place of the plug 82 as will be subsequently more fully described.

A stylet needle generally designated 86 comprises, at the forward end 90 thereof, a relatively short, hollow or cannulated tubular steel needle having a central bore 89 (best shown in FIG. 3) and a sharpened bevel point 88 which is capable of penetrating the skin, the subcutaneous tissue and a body cavity such as a blood vessel of a patient. In the assembled relation illustrated in FIG. 3, it can be observed that the needle 86 projects a short distance beyond the tip 41 of the catheter 44 for purposes of insertion of the catheter 42 into the blood vessel. The proximal end 91 of the needle 86 is curved through essentially 90.degree. and terminates in a looped end or tail 92. Thus, a tortuous passageway 98 is formed rearward adjacent the proximal end 91 of the needle 86.

A resilient flexible tab, generally designated 94, surrounds the looped end or tail 92 of the needle 86 immediately above the proximal end 91 thereof. The tab 94 is preferably substantially transparent and is fluid-sealed around a substantial portion of the tail 92. The terminal end 93 is disposed within an interior cavity 96. Thus, when the tab 94 is squeezed between the fingers, air will be forced out of the cavity 96 through the tortuous passageway 98 and out through the end 88 of the needle 86. Subsequent to venipuncture, the pressure on the tab 94 may be released and the resiliency or memory of the material comprising the tab will cause the cavity 96 to expand to its original, non-collapsed position thereby aspirating blood from the vein of the patient to the cavity 96 interior of the tab 94 and thus visually demonstrating a successful venipuncture.

If desired, the tab embodiment generally designated 104 illustrated in FIG. 6 may be substituted for the tab 94. In the embodiment of FIG. 6, the tab material is bonded to the needle 86 at 106 which needle terminates at 108, a short distance into the tab. A substantially transparent chamber 110 is disposed in the tab 104 above the end 108 of the needle 86. The chamber 110 communicates with the exterior of the tab 104 through a bleeder opening 112 which provides an air passageway into and out of the chamber 110. Thus, when a successful venipuncture is performed, blood will flow through the needle 86 by reason of the normal blood pressure and capillary action to the chamber 110 where it can be readily observed. Air which exists in chamber 110 will be exhausted through the bleeder opening 112. However, the opening 112 is sufficiently constricted so as to substantially inhibit any outflow of blood.

The needle 86 may be modified (as shown in FIG. 7), if desired, to provide a peripheral aperture 120 adjacent the curved proximal end 91 thereof. The aperture 120 is disposed in the surface of the needle 86 which is essentially parallel to the bore 78 adjacent the outside angle created by the curved end 91. When an aperture 120 is provided in the needle 86, the guide core 60 is provided with an internal protuberance or seal 122 which, in the assembled position, substantially occludes the aperture 120 in the needle 86. When desired, the needle 86 may be retracted slightly rearwardly so that the shank 90 thereof will rest upon the nub 122, accommodating, thereby, free flow of fluid through the bore 78 of the core 60 and the hollow 89 of the needle 86 through the aperture 120.

FIG. 8 illustrates another presently preferred needle embodiment generally designated 126 which may be used with the infusion assembly of FIGS. 1 and 2. Needle 126 may be essentially identical to the needle 86 except needle 126 is provided with a heel 128 adjacent the curved portion 130 thereof which is rearwardly offset along the axis of the core 60. The heel portion 128 restrains the needle 126 within the jacket 58 to inhibit inadvertent protraction and retraction of the needle 126 relative to the guide core 60.

If desired, the self-sealing jacket 134 illustrated in FIGS. 9-11 may be substituted for the jacket 58. The jacket 134 is substantially the same as jacket 58 except jacket 134 comprises a raised puncture site 136 the proximal end 138 of which is disposed flush with the end 54 of the outer sleeve 48 (FIG. 2) and the distal end 139 of which seats contiguous adjacent the end 52 of the slot 50 in the outer sleeve 48. Thus, the raised puncture site 136 is disposed within and substantially fills the slot 50 in the outer sleeve 48. The increased thickness of the jacket 134 at the puncture site 136 maximizes the self-sealing capacity of the jacket 134 when the needle 86 or 126 is removed therefrom.

FIGS. 12 and 13 illustrate another presently preferred infusion assembly embodiment generally designated 150. The infusion assembly 150 is substantially the same as the infusion assembly 30 and like parts are given corresponding numbers throughout.

Referring primarily to the differences in the embodiment comprising FIGS. 12 and 13 your attention is directed to the outer sleeve generally designated 153 which differs from the outer sleeve 48 in that a transverse aperture 152 communicates the hollow 56 of the outer sleeve with the exterior thereof. As is illustrated particularly in FIG. 16, the aperture 152 preferably extends through diametrically opposed sides of the outer sleeve 153 and is located adjacent the axial midpoint of the sleeve. Clearly, any suitable number of apertures could be provided in the outer sleeve 153 at essentially any desired location.

It should also be observed that the catheter 42 is in no way secured to the tapered projection 44 or elsewhere on the outer sleeve 153. On the contrary, the catheter 42 has an enlarged conical shape at the proximal end 157 which is bonded or otherwise secured to the male fitting 62 at the leading end of the inner core generally designated 155 (see FIGS. 13 and 15).

The inner guide core 155 differs from the guide core 60 in that a transverse aperture 154 is disposed laterally therethrough as best illustrated in FIGS. 15 and 16. It is essential that apertures 152 and 154 are coaxially disposed when the infusion assembly 150 is in the assembled position. With apertures 152 and 154 aligned, it is possible to connect an adapter or coupling generally designated 156 (FIGS. 16 and 17) into the assembly as shown in FIG. 14. The coupling 156 preferably comprises a cylindrical fitting 158 terminating in a forward, essentially planar front face 162 which is continuous with a forwardly projecting shank 170. The shank 170 tapers forwardly at 172 to define a diametrally reduced throat 174. The throat 174 defines the base of an annularly enlarged crown 176 which tapers forwardly to the terminal end 168 thereof. The cylindrical fitting 158 has a central bore 160 (FIG. 16) which is reduced in dimension to define an internal abutment surface 166 and is continuous with diametrically reduced axial bore 164 communicating the bore 160 with the exterior at the end 168 of the coupling 156. The bore 160 selectively receives in press-fit or luer lock relation a mating coupling (not shown) from conventional fluid delivery apparatus (not shown) or the leading end of a conventional syringe, e.g., syringe 222 in FIG. 19.

The coupling 156 is selectively capable of penetrating the self-sealing jacket 58 through apertures 152 and 154 in the outer sleeve 153 and the inner core 155 respectively. Thus, if desired, fluid may be communicated to the catheter 42 through either the hollow 78 of the core 155 or through the bore 164 of the coupling 156 or both simultaneously.

If desired, the embodiment of FIG. 18 may be used in place of the embodiments of FIGS. 1 and 12. The embodiment of FIG. 18 comprises a novel guide core generally designated 186 which comprises a forwardly tapered projection 188 which is diametrically reduced at 190 and integrally secured thereat to the catheter 42. The cylindrical body 192 of the guide core 186 is provided with spaced annular flanges 194 which define a seat for the self-sealing jacket 58. The guide core 186 is provided with a central bore 200 comprising a fluid passageway from the proximal end 198 of the guide core 186 to the catheter 42. The central bore 200 may be provided with conventional luer dogs (not shown) and may accommodate conventional fittings adjacent the proximal end 198 thereof so that delivery tubes and/or syringes or the like may be connected thereto. The guide core 186 is provided with an axial slot (not shown) disposed in the cylindrical body 192 accommodating passage of the needle 86 through the jacket 58 to the interior of the guide core 186 and the catheter 42. If desired, transverse apertures for receiving coupling 156 (FIG. 17) may also be located at predetermined locations in the periphery of the guide core 186.

FIGS. 19-22 illustrate still another presently preferred embodiment of the invention. In FIG. 19, the infusion assembly 30 is illustrated in the assembled condition with the stylet needle 86 and finger tab 94 removed. The catheter 42 has been previously located in a vein (not shown) in the arm 199 of a patient. A piece of adhesive tape 201 has been placed across a portion of the arm 199 adjacent the puncture site as is conventional. The infusion assembly is connected to a leading end 210 of a fluid delivery tube, generally designated 209 by a coupling generally designated 202. The coupling 202 comprises a forwardly tapered male fitting 204 which is adapted to fit within the central bore 78 of the guide core 60 (see FIG. 2). The fitting 204 is integral with an annular collar 206 and laterally opposed wings 208 which accommodate easy manipulation of the fitting 204 for attachment purposes. The connection 202 is centrally hollow (not shown) to communicate fluid from the delivery tube 209 to the interior of the catheter 42.

An intermediate portion of the tube 209 is provided with a novel guide core 218, shown in FIG. 21. The inner guide core 218 has a forward projection 212 adapted to be press-fit into the leading end 210. The inner core 218 is provided with a central bore 215 which extends through the entire length thereof and which is adapted to receive the leading end 220 of a coupling (not shown) connecting the core 218 to a trailing end 240 of the delivery tube 209.

The inner core 218 may be provided with a transverse aperture 216, best shown in FIG. 20, and telescopically carries thereupon the self-sealing jacket 58. Thus, an adapter or coupling 156 (FIG. 17) may be selectively inserted into the inner core 218 through the jacket 58 to accommodate connection of the leading end 224 of a conventional syringe 222 or the like. Clearly, if desired, another fluid delivery tube could be connected to the guide core 218 through the coupling 156 instead of the syringe.

The trailing end 240 of the delivery tube 209 is connected in a conventional manner to the neck 246 disposed in the tapered surface 244 of a conventional fluid dispensing bottle 242 or the like. Although a fluid dispensing bottle 242 is illustrated in FIG. 19, it should be appreciated that any fluid dispensing apparatus such as plastic bottles, and other dispensing containers may be used.

Referring now to FIG. 22, a Y-shaped adapter 226 is illustrated which may be used to connect the trailing end 240 of the delivery tube 209 to the leading end 210 thereof. The adapter 226 comprises a main branch 228 which is interiorly connected at one end in press-fit relation to a coupling (not shown) having a peripherally enlarged flange 230. The flange 230 is integrally connected to the trailing end 240 of the delivery tube 209. The other end of the main branch 228 (not shown) is similarly coupled to the leading end 210 of the delivery tube 209. A secondary branch 232 opens exteriorly at the end 235 and is provided thereat with a resilient self-sealing cup 234 formed of latex rubber or the like. The latex cup 234 is sealed to the branch 232 at the interface between the edges 236 of the cup 234 and the periphery of the branch 232. The cup 234 is adapted to be penetrated at 238 by the coupling 156 (see FIG. 17). Thus, a plurality of fluids may be communicated at once through the delivery tube 209.

In the method of using the presently preferred embodiments of the invention reference is made particularly to the embodiments of FIGS. 12-17 and 19, it being understood that the remaining disclosed embodiments are used in a like manner.

With the apparatus in the assembled condition of FIG. 12, the plug 82 is removed and a fluid delivery tube is connected to the core 155. If desired, fluid may be then communicated into the core adjacent the needle 86.

The technician or other user of the apparatus initially grasps the tab 94 between the fingers and squeezes the sides together to expel air within the tab 94. The needle cover 32 is removed and the needle is placed within the lumen of a vein according to conventional venipuncture techniques. The success of the venipuncture can be visually demonstrated by releasing pressure on the tab 94 and aspirating blood from the vein into the tab 94.

Thereafter, the needle 86 may be removed by withdrawing the needle 86 from the catheter 42 through the self-sealing jacket 58. Fluid will then immediately pass into the vein through the catheter 42. When desired, after the needle 86 has been removed, the fluid coupling 156 may be forced to the interior of the guide core 155 by penetrating the jacket 58 as illustrated in FIGS. 14 and 16. Either before or after penetration of the jacket 58 by the coupling 156, another fluid delivery tube (not shown) may be suitably connected to the coupling 156 so that when penetration is complete, the fluid passing through the coupling 156 will be communicated through the catheter 42 to the vein simultaneously with the fluid passing directly through the bore 78 of the core 155.

Similarly, if a core 218 (FIG. 21) is disposed intermediate of a fluid delivery tube, the fluid coupling 156 may be disposed therein to accommodate injection of medication or other fluids into the fluid delivery tube. It should be appreciated that the needle 86 may be properly placed directly within the patient's vein to withdraw a small blood sample or the like. The needle 86 may also be caused to penetrate the wall of a catheter tube to obtain a sample when the catheter tube is already indwelling. When a properly sized catheter tube is not initially indwelling, the needle can be used to cause a venipuncture and to place the catheter tube within a vein. When the catheter tube is formed of self-sealing material, the needle may be removed while the catheter tube remains indwelling.

From the foregoing it is apparent that the novel invention described accommodates removal of the stylet needle and subsequent fluid delivery through a catheter without the interchange of coupling parts and, significantly, provision is made for the simultaneous administration of a plurality of fluids through the same catheter. The unique stylet needle and integral tab make it possible to visually observe the completion of a successful venipuncture through aspiration of blood into a transparent reservoir.

FIGS. 23, 24, and 25 illustrate another presently preferred infusion assembly embodiment, indicated generally at 242 in FIG. 23. The infusion assembly 240 is substantially the same as the infusion assembly 30 of FIG. 1 and similar parts have been given similar reference numbers.

Referring primarily to the differences in the embodiment of FIGS. 23 through 25, the outer sleeve 244 comprises a central bore 246 having an inwardly and forwardly tapering throat 248 at the distal and therefore terminating in a bore 250 of reduced diametral dimensions, as best seen in FIG. 25. Moreover, the axially disposed slot 252 is terminated short of the proximal end 254 of the outer sleeve 244 and is provided with an outwardly and rearwardly inclined surface 256 and has a portion 258 of enlarged transverse dimension adjacent the distal end of slot 252.

The catheter 42 is similar to that of FIGS. 13 and 15 having an enlarged conical shape at the proximal end 157 which is fixedly secured, by bonding or the like, to male guide core fitting 260. The male guide core fitting 260 is externally dimensioned to fit snugly within the bore 246 and throat 248 of outer sleeve 244, as seen in FIG. @%, AND IS PROVIDED WITH A PLANAR SURFACE @"@ AT THE PROXIMAL END THEREOF FOR ABUTMENT BY THE DISTAL END OF THE SELF-sealing jacket 58. As shown in FIG. 25, the proximal end 254 of the outer sleeve 244 extends beyond the proximal end of the self-sealing sleeve 58 so that bore 246 of outer sleeve 244 forms a socket 264 for receiving the male fitting 80 of plug 82 or a fluid delivery tube, such as tube 210 of FIG. 19. A gap exists at 265 between the forward end of the sleeve 58 and the male fitting 260 so that, after removal of the needle, the sleeve 58 may be displaced in a forward direction within outer sleeve 244 by applying force on the trailing end thereof to position the needle perforation in the sleeve 58 next to the inside wall of outer sleeve 244 and thereby positively insure that no leakage will occur through the perforation.

The stylet needle 86 is formed with a pair of opposing, right-angle bends 266 and 268 adjacent the proximal end 270 thereof and the end 270 is press-fit into the bore 272 of a needle jacket 274. The bore 272 of needle jacket 274 extends axially completely through the jacket 274 and a slot 276 adjacent the distal end of the jacket 274 communicates the slot 276 with the exterior of jacket 274 to receive the portion 278 of needle 86 between bends 266 and 268. Adjacent the proximal end of jacket 274, the bore 272 has a socket 280 of enlarged diametral dimensions to receive the male fitting 282 of a plug 284 which is preferably transparent. The plug 284 is formed with a bore 286 extending axially there through which has a portion 288 of reduced diametral dimension communicating with the proximal end of the plug 284.

To assemble the infusion unit 242, as shown in FIGS. 23 and 25, the stylet needle 86 is inserted through the self-sealing sleeve 58 and catheter 42. When a venipuncture is performed, blood will flow through needle 86 and into bore 286 of plug 284 due to natural blood pressure to indicate a successful venipuncture. Thereafter, the needle 86 may be removed. Either before or after the venipuncture has been performed, plug 82 may be removed from the proximal end of outer jacket 244 and replaced by a fluid delivery tube, such as tube 210 of FIG. 19. In addition, if desired, plug 284 may be replaced by a fluid delivery tube, such as tube 210, prior to the venipuncture to provide fluid at the tip of the stylet needle 86 at the instant of venipuncture.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore to be embraced therein.

Claims

What is claimed and desired to be secured by United States Letters Patent is:

1. A stylet catheter assembly comprising:

an essentially linear catheter tube of pliable material defining the major axis of the assembly and having a forward tip to be introduced into the vein of a patient;

an exterior female fitting in the nature of a substantially rigid sleeve attached to the trailing end of the catheter tube, said fitting comprising a hollow bore which opens at the trailing end thereof and an exposed side wall having an elongated opening in the side wall;

an elastomeric hollow self-sealing jacket generally axially situated within and essentially contiguous to the hollow bore of the fitting, the jacket being laterally exposed to the exterior at said elongated opening;

a circuitously shaped elongated piercing means axially coextensively disposed within the catheter tube and comprising a forward sharpened end extending beyond the forward tip of the catheter tube and a handle at the trailing end of the piercing means, an intermediate portion of the piercing means angularly extending through the jacket and through the side wall of the fitting at the elongated opening and;

separate hollow guide means situated within the female fitting adjacent the trailing end of the catheter tube through which the piercing means extends, which guide means restricts to and fro displacement of the piercing means within the catheter tube to movement along said major axis.

2. In an assembly as defined in claim 1 wherein said jacket comprises an outwardly projecting thickened portion which essentially fills the elongated opening in the fitting and through which the piercing means passes.

3. In an assembly as defined in claim 1 wherein said angularly extending portion of the piercing means comprises a curvilinear configuration.

4. In an assembly as defined in claim 1 wherein the angularly extending portion of the piercing means comprises a laterally offset portion defining a heel in the piercing means to gently resist movement of the piercing means into or out of the jacket.

5. In an apparatus as defined in claim 1 wherein the piercing means comprises a needle and wherein the handle comprises a resiliently flexible tab and forms an enclosure around the terminal end of the needle, the tab being essentially transparent at least adjacent the location of the enclosed terminal end of the needle so that the tab may be finger-compressed prior to venipuncture to expel air from the enclosure and released after venipuncture to aspirate blood through the needle to evince completion of a proper venipuncture.

6. In an apparatus as defined in claim 1 wherein the piercing means comprises a needle and wherein the handle comprises a tab which is provided with a visually observable fluid reservoir communicating with the proximal end of the needle and also with the exterior of the tab through a small opening whereby blood will flow into the reservoir and become visually observable upon the completion of a successful venipuncture.

7. The catheter assembly of claim 1 wherein the piercing means comprise a hollow needle and the handle comprises an interior hollow pocket for causing flashback.

8. The catheter assembly of claim 1 wherein the jacket is interposed between the sleeve and the guide.

9. The catheter assembly of claim 1 wherein the jacket and the guide are serially disposed within the sleeve along said axis.

10. The catheter assembly of claim 1 wherein the handle is partially hollow for accommodating aspiration and flashback and partially solid for accommodating venipuncture.

11. The catheter assembly of claim 1 wherein the jacket comprises a thick radially projecting portion disposed within the side wall opening of the female fitting.

12. The catheter assembly of claim 1 wherein said side wall opening of the female fitting comprises a ramp surface for directing displacement of the piercing means.

13. A stylet catheter assembly comprising a hollow catheter tube, an outer sleeve integral with the catheter tube, an internal guide core disposed within the sleeve, a penetrable self-sealing inner jacket interposed between the outer sleeve and the guide core, and a stylet comprising a hollow needle which comprises an elongated linear leading portion extending through and beyond the catheter tube and a curvilinear terminal portion which projects through the jacket and out the side of the sleeve, a handle secured behind the curvilinear terminal portion, the stylet being adapted to (1) selectively penetrate the inner jacket through openings in the outer sleeve to a position telescopically within the catheter for insertion of the catheter into the lumen of a vein and (2) be completely removed from the catheter after venipuncture with negligible loss of blood the curvilinear portion of the needle further comprising an aperture disposed adjacent the linear portion and the inner guide core further comprising an inwardly-projecting protuberance which, when the needle is in a predetermined position, obstructs the aperture therein and, when the needle is moved from the predetermined position, maintains the aperture in an unobstructed location thereby providing fluid communication through the aperture and the needle.

14. A stylet catheter assembly comprising a concentric arrangement of parts comprising:

a pliable substantially linear catheter tube which defines an axis;

a substantially rigid female sleeve fitting attached to the proximal end of the catheter tube;

a generally hollow guide core disposed concentrically within the female fitting and having an annular wall with a forward distal central bore the axis of which is common with the axis of the catheter tube, the guide core having a side slot and a side aperture adjacent but spaced one from the other, each being essentially transverse to said axes;

a resilient elastomeric sleeve disposed concentrically within the female sleeve fitting between the fitting and the guide core so as to seal the slot, aperture and hollow of the guide core.

15. In an assembly as defined in claim 14 further comprising a hollow fluid coupling comprising a forwardly-tapered outwardly-projecting leading end removably inserted through an aperture in the female fitting the aperture in the guide core and the elastomeric sleeve in fluid-sealed relation the hollow fluid coupling also comprising a female connection adapted to receive conventional male infusion connectors whereby infusion of the fluid through the coupling into the catheter is accommodated.

16. In a stylet catheter assembly comprising an internally hollow guide core which has a peripherally disposed elongated side wall opening communicating with the hollow of the guide core to the exterior thereof and an aperture offset from the elongated opening; a fluid impervious resiliently flexible sleeve superimposed upon the guide core in fluid-sealing relation; an elongated hollow catheter tube in coaxial relation with the hollow core; and an outer housing superimposed over the flexible sleeve and guide core, the outer housing having an axially elongated slot which, in the assembled position, is aligned with the side wall opening in the guide core and an aperture aligned with the aperture in the core; and tortuously shaped elongated piercing means extending through the slot, the sleeve, the side wall opening, both apertures and the catheter tube.

17. An intravascular catheter assembly comprising a linearly directed hollow plastic catheter to be placed in the cardiovascular system via venipuncture, the improvement comprising hollow venipuncture structure for intravascular therapy comprising an elongated tortuously configurated shaft comprising a linearly extending portion disposed within the hollow of the plastic catheter, and terminating in an exposed sharp leading tip, an intermediate portion integral with and extending at least partially transverse of the linearly extending portion through a hole in the side of the linear catheter and a handle integral with the intermediate transverse portion, the handle comprising a blood flashback chamber in fluid communication with the interior of the intermediate portion.

18. The improvement of claim 17 wherein the shaft is hollow and the handle comprises a hollow aspirating tab, the hollow of the tab being connected to the hollow of the shaft for at least partial manual evacuation of air from the shaft prior to venipuncture and vacuum driven flashback after venipuncture.

19. The improvement of claim 17 wherein the shaft is hollow and the handle comprises an infusion fitting for placing fluids into a patient through the hollow of the shaft upon venipuncture.

20. The improvement of claim 17 wherein the transverse intermediate portion of the shaft is interposed between two short curved portions.