U.S. patent number 3,595,230 [Application Number 04/747,502] was granted by the patent office on 1971-07-27 for intravenous catheter placement unit with tubular guide sheath.
This patent grant is currently assigned to Abbott Laboratories. Invention is credited to Dean R. Katerdahl, George M. Suyeoka.
United States Patent |
3,595,230 |
Suyeoka , et al. |
July 27, 1971 |
INTRAVENOUS CATHETER PLACEMENT UNIT WITH TUBULAR GUIDE SHEATH
Abstract
A catheter placement unit including a catheter shield with a
catheter and needle positioned therein and the catheter shield
comprising a flexible tubular hollow body having its distal end
closed by a frictionally engaged end plug and having a slot of
varying width extending through its distal end to a point adjacent
but not through its proximal end for guiding the catheter and
needle preparatory to and during venipuncture.
Inventors: |
Suyeoka; George M. (Chicago,
IL), Katerdahl; Dean R. (Wheaton, IL) |
Assignee: |
Abbott Laboratories (Chicago,
IL)
|
Family
ID: |
25005330 |
Appl.
No.: |
04/747,502 |
Filed: |
July 25, 1968 |
Current U.S.
Class: |
604/192; 206/365;
604/171 |
Current CPC
Class: |
A61M
25/0612 (20130101) |
Current International
Class: |
A61M
25/06 (20060101); A61m 005/00 () |
Field of
Search: |
;128/214.4,221,348,349,DIG.16 ;206/63.2 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Truluck; Dalton L.
Claims
Having described this invention in full, clear, and concise terms,
what We claim is:
1. A catheter placement unit comprising
a catheter having a fin extending therefrom;
a needle movably disposed inside said catheter and having a tab
extending therefrom; and
a tubular shield slidably housing said catheter and said needle,
said shield having slot means therein including a first narrow
slot, and a second slot wider than said first slot and having
shoulders communicating with said first slot,
said catheter fin and said needle tab extending through said slot
means to a position external of said shield, said catheter fin
having a width less than the width of said second slot and movable
from said second slot to said first slot, and said needle tab
having a width to abut said shoulders of said second slot whereby
said needle tab is prevented from movement from said second slot to
said first slot.
2. The invention as recited in claim 1 wherein said slot means
includes a third slot, said shoulders in said second slot include a
first pair of squared shoulders, said second slot has a second pair
of squared shoulders, and a tapered neck communicates with said
second pair of squared shoulders in said second slot and said third
slot whereby said needle tab may be moved into said second slot
from said third slot via said tapered neck and confined therein by
said first and second pairs of squared shoulders.
3. The invention as recited in claim 2 wherein said shield has an
open distal end, and said first, second, and third slots are
disposed in said shield in consecutive, longitudinal alignment from
said distal end.
4. A catheter placement unit comprising
a catheter having a proximal end and a fin extending radially from
said proximal end;
a needle slidably disposed in said catheter having a proximal end
extending beyond said proximal end of said catheter and a tab
extending radially from said proximal end of said needle; and
shield means including a flexible hollow tubular body enclosing
said catheter and said needle and having an open distal end, a
removable end plug frictionally secured in said distal end of said
body having a bore extending therethrough receiving said needle and
said catheter, and guide means in said body to guide movement of
said catheter fin and said needle tab,
said guide means including first slot means communicating with said
distal end of said body and having a first width, and second slot
means communicating with said first slot means and having a second
width greater than said first width, said first and second slot
means being consecutively longitudinally arranged in said body from
said distal end, and
said catheter fin and said needle tab extending through said guide
means to a position external of said body, said catheter fin having
a width less than said second width of said second slot means and
movable to said first slot means from said second slot means, and
said needle tab having a width substantially equal to said second
width of said second slot means whereby said needle tab is confined
in said second slot means.
5. The invention as recited in claim 4 wherein said end plug
includes a first half, a second half and a resilient strip
interconnecting said first and second halves and normally forcing
said first and second halves apart whereby said first and second
halves are held together when frictionally secured in said distal
end of said body and are moved apart when said end plug is pushed
out of said body by said catheter fin to fall free from said
catheter.
6. The invention as recited in claim 4 wherein said guide means
includes third slot means in communication with said second slot
means, and said catheter fin and said needle tab have first
positions extending through said third slot means and are movable
to second positions through said third slot means wherein said
needle tab is confined in said second slot means and said catheter
fin is in position to be moved through said first slot means to
said distal end of said body.
7. The invention as recited in claim 6 wherein said second slot
means has squared edges, and said third slot means has a first neck
therein to define an area for maintaining said needle tab in said
first position and communicates with said second slot means through
a second tapered neck.
Description
BACKGROUND OF THE INVENTION
In the use of long intravenous catheters, problems have been
encountered in providing a catheter which can be safely and easily
positioned in a vein. Modern practice has tended toward the use of
a concentric needle and catheter assembly which is inserted into a
vein whereby the catheter may be advanced into the vein after
venipuncture while the needle is withdrawn from the vein. Two
general types of concentric intravenous catheters have evolved, the
first type being known as the "needle outside," and the second type
being known as the "needle inside."
Turning to a consideration of needle-inside type long intravenous
catheters, the primary disadvantages are the flexibility of a long
slender needle and the difficulty in maintaining the sterility of
the catheter. These disadvantages are somewhat self-explanatory,
but a further consideration is desirable to appreciate the novelty
of this invention.
When it is desirable to use long flexible needles in order that the
catheter be properly placed in the vein, these needles must be
handled at a hub provided at one end. By grasping one end of the
needle, accurate positioning of the opposite end is extremely
difficult and the flexibility of the needle further makes the
needle difficult to control. To solve this problem various devices
have been heretofore used to grasp the needle at an intermediate
point, but this increases the possibility of contamination.
An additional disadvantage is the danger of contamination involved
in inserting a manually manipulated instrument into the body; this
problem is increased when the needle-catheter is grasped
intermediate its length.
Heretofore, the sterility problem attendant with the use of long
needles was dealt with by using an aseptic venipuncture technique.
Also, the sterility has been improved by packaging the catheters in
plastic envelopes and by using various flexible sheaths to surround
the catheter during venipuncture. These devices are not entirely
satisfactory since the catheter and needle must be moved relative
to one another after venipuncture and the flexible sheaths inhibit
the advancement of the catheter.
SUMMARY OF THE INVENTION
This invention broadly relates to catheters of the needle-inside
type. More specifically, the invention relates to a combined
catheter shield and catheter placement unit adapted for use with
catheters of the needle-inside type. Although this invention
relates particularly to the needle-inside type, it also solves many
problems which are common to the needle-outside type.
The present invention treats the primary disadvantages by combining
the previously used devices in a novel manner. That is, an
enclosing sheath with a supporting structure intermediate the
catheter length is provided wherein the resulting novel structure
allows movement of the catheter and needle either simultaneously or
separately and during positioning of the catheter, and wherein the
catheter can be readily freed of the needle and sheath after
positioning.
Briefly, the present invention provides a flexible but rigid
tubular sheath with slots which slots receive fins attached to a
needle and a catheter enclosed in said sheath which are to be
grasped to move the needle and the catheter. A series of slots is
provided in the sheath which will lock the needle in place in the
sheath and allow advancement of the catheter until the catheter is
completely free of the sheath and the needle. Additionally, the
sheath is provided with an end plug to support the needle and
catheter during venipuncture which plug is freely removable from
the catheter when the catheter is free of the sheath.
Accordingly, it is a primary object of this invention to provide a
catheter sheath which maintains the sterility of a catheter and
needle assembly, which supports the catheter-needle assembly during
venipuncture and which is automatically separated from said
catheter when the catheter is advanced into position in the
vein.
Still another object is to provide a catheter placement unit
wherein a needle and catheter may be moved to a venipuncture
position and the catheter may thereafter be advanced to
automatically separate the catheter from the needle and sheath.
Other objects and advantages will become apparent from a reference
to the drawings and the descriptions thereof. In the drawings, like
numerals designate like elements and in the drawings:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view partly in section showing the catheter
placement unit of this invention;
FIG. 2 is a top view of the catheter placement unit of this
invention;
FIG. 3 is an end view of an end plug according to this
invention;
FIG. 4 is a side view of an end plug according to this
invention;
FIG. 5 is a side view of a catheter with appurtenances according to
this invention;
FIG. 6 is a side view of a needle with appurtenances according to
this invention;
FIG. 7 is a view of a catheter with appurtenances in place in a
patient's vein;
FIG. 8 is a partial top view of a shield according to this
invention;
FIG. 9 is a sectional view along lines 9-9 of FIG. 8;
FIG. 10 is a partial side view of a needle according to this
invention;
FIG. 11 is a sectional view along lines 11-11 of FIG. 10;
FIG. 12 is a partial side view in partial section of a catheter
according to this invention;
FIG. 13 is an end view along lines 13-13 of FIG. 12.
PREFERRED EMBODIMENT
Referring to the drawings, the novel shield and the intravenous
catheter is shown as comprising the following major elements:
2-shield
4-end plug
6-catheter
8-catheter fin
10-catheter hub
12-needle
14-needle hub
16-needle thumb tab
18-air filter
The assembly of these components can best be seen by reference to
FIG. 1. In this figure, the end plug 4 is shown as a tubular
element with a flanged end 21, a tapered end 20, and an aperture
22. The end plug 4 fits within shield 2 and engages the catheter 6
having needle 12 concentrically arranged therein. The exact
construction of the end plug 4 will be described in detail
hereinafter with reference to other figures. As a result of the
engagement of catheter 6 and needle 12 in aperture 22, they are
supported and guided by end plug 4 when said catheter and needle
are slidably moved therethrough. This is important since the long
flexible needle is thereby steadied and rendered manipulatable
without danger of contamination or breakage during venipuncture. A
correlative advantage is the fact that the end of the shield 2
containing end plug 4 aids in maintaining the integrity of the
entire device during storage and shipment.
Returning to FIG. 1, the tubular shield 2 is seen to completely
enclose the catheter 6 and has extended tubular portion 3 connected
to extended tubular portion 7 of lesser diameter than tubular
portion 3 by tapered tubular portion 5. The shield extends from the
distal end, i.e., the catheter end engaged by end plug 4 to the
proximal end, i.e., the end of catheter 6 which is provided with
catheter hub 10. The catheter hub 10 carries a catheter fin 8 for a
purpose to be described more fully hereinafter. Needle 12 is
concentrically arranged within catheter 6 in the usual "needle
inside" catheter arrangement. As seen in FIG. 1, the needle tip 24
extends beyond the catheter at its distal end. Needle 12 has a
needle hub 14 with an upstanding needle thumb tab 16 at its
proximal end. Needle hub 14 is engaged within catheter hub 10. The
open end of needle hub 14 is closed by an air filter 18. This
filter is a hollow tubular element having one end closed at flange
19. Flange 19 contains a fiberglass mesh component which allows air
to be expelled from the hollow needle 12 through the hollow needle
hub 10, however, the structure of the mesh is such as to prevent
flow of blood therethrough when flashback occurs during
venipuncture. In order to accommodate the upstanding catheter fin 8
and needle thumb tab 16, the shield 2 is slit longitudinally as is
best seen in FIGS. 2 and 8.
In FIG. 2, reference numeral 52 generally designates a series of
slots of varying width in one side of shield 2. Reference 26
designates a small slot formed in one side of tubular plastic
shield 2; small slot 26 extends from the distal end of the shield 2
which end carries end plug 4 to a point about half the length of
the shield. The small slot 26 is normally urged in a closed
position due to the inherent resiliency of the plastic shield 2. As
the small slot 26 continues into the second half of the shield
length a first tapered neck 27 is provided and then an intermediate
slot 28; next a first large slot 29 is provided followed by a
second tapered neck 30 leading to a second large slot 31 which
extends almost to the end of the shield. This second large slot 31
is followed by a third tapered neck 32 and then a third large slot
33. The function of the slots is to allow controlled movement of
catheter fin 8 and needle thumb tab 16 which thereby move the
catheter 6 and needle 12 respectively within the shield 2. To
understand the purpose of the slots, it is necessary to consider
the overall operation and use of the instrument.
In practice, a catheter is inserted into a vein for the purpose of
inserting a treating fluid into the body. In accordance with
conventional needle-inside catheter practice, a needle is
concentrically arranged within the catheter so that venipuncture
can be made and the catheter can be moved forward while the needle
is removed. When the catheter is in place and the needle removed,
administration equipment is connected to the catheter hub. Now, the
improvement of this invention can be appreciated. The shield
enables the assembled needle and catheter to be manipulated and
handled without contamination, and the end plug provides a
stabilizing force intermediate the needle length. Of course, the
shield 2 and end plug 4 must be removed after venipuncture to
enable the easy and efficient administration of treating fluid. In
using the novel placement unit of this invention, the needle thumb
tab 16 initially extends from shield 2 through the third large slot
33. Prior to use, needle thumb tab 16 is held in place by the third
tapered neck 32, and air filter 18 extends from the shield 2. Also
catheter fin 8 initially extends through the second large slot 31.
In this initial state, catheter hub 10 engages needle hub 14 so
that movement of one fin or tab causes movement of the other.
Preparatory to venipuncture, the user pushes the needle thumb tab
16 forward through third tapered neck 32 into second large slot 31;
thereby forcing the entire assembled needle and catheter forward,
and causing the needle tip 24 to slightly extend from the distal
end of the shield. Thereafter, catheter fin 8 is moved into
intermediate slot 28 and needle thumb tab 16 is positioned in first
large slot 29, by pushing the needle thumb tab 16 forward through
second tapered neck 30. This may be accomplished in a single
movement. At this point it is to be noted that needle thumb tab 16
has a width which is approximately the same as first and second
large slots 29 and 31. The needle thumb tab 16 is able to move
through second tapered neck 30 because it is tapered and as it
moves therethrough the resilient walls of shield 2 are spread
apart. This is the mechanism also for pushing the catheter fin
through those slots that are not as wide as said catheter wing.
However, once needle thumb tab 16 reaches first large slot 29 it is
confined by the relatively squared edges of said slot and can only
be moved by considerable effort in forcing the shield sides apart.
Thus, needle thumb tab 16 is not intended to be subsequently moved
once it is positioned in first large slot 29. As noted above, when
needle thumb tab 16 is positioned in first large slot 29, the
catheter fin 8 is simultaneously positioned in intermediate slot 28
and the concentric needle and catheter are moved further through
aperture 22 in end plug 4 so that about one-third the length of
said catheter and needle now extend from shield 2. Now venipuncture
may be accomplished with the needle steadied by end plug 4, and the
catheter may be advanced after the needle penetrates into the vein.
The advance of the catheter is accomplished by grasping catheter
fin 8 with the fingers of one hand and using the other hand to hold
the shield 2. For maximum efficiency the other hand may engage
shield 2 adjacent first large slot 29 thereby ensuring that the
needle will remain stationary due to the engagement of the needle
wing 16 in first large slot 29, but this is not generally required
since first large slot 29 closely engages needle thumb tab 16 and
immobilizes the needle. Continuing in the description, catheter fin
8 is forced forward through first tapered neck 27 into small slot
26. Since the needle 12 is now held immobilized in the shield the
catheter 6 will be advanced into the vein and separated from the
needle 12. In order to free the catheter and catheter hub from
shield 2, the end plug 4 is adapted to be pushed out of the shield
and to fall free of the catheter, thus leaving the catheter in the
vein and the catheter hub free for attachment to administration
equipment as seen in FIG. 7.
The end plug is designed so as to be freely removable from the
catheter 6 after it is forced out of the end of the shield 2. The
construction of the end plug is shown in FIGS. 3 and 4. End plug 4
comprises a first half 35 and a second half 37 attached by a strip
39. First half 35 is provided with a lug 41 and second half 37 is
provided with a cavity 43 aligned with lug 41. When the halves are
placed in abutting relationship, lug 41 engages cavity 43 to
prevent relative movement of the halves (see FIG. 3). Since the two
halves are connected by resilient strap 39, they normally are
forced apart as shown in FIG. 4 due to the resiliency of strip 39.
Therefore, unless some restraining force is applied to the halves
to force the halves into the position of FIG. 3, they will assume
the position of FIG. 4. The advantage of this characteristic is
that the end plug 4 when positioned in shield 2 forms an integral
plug, but as soon as it is pushed out, it flies apart and falls
free of catheter 6.
The details of construction of the catheter can be seen in FIGS. 5,
7, 12 and 13. As above-described, FIG. 7 shows the catheter in
place in a vein. The catheter 6 comprises a hollow transparent or
translucent plastic tube of any suitable length. The plastic
catheter may comprise a length of extruded plasticized polyvinyl
chloride, polypropylene or other synthetic plastic. One typically
used catheter of the intermediate length is approximately 5 inches
long, although the length can vary greatly and is in no way
critical to the success of this invention. At the proximal end, the
catheter 6 is provided with a catheter hub 10 having a catheter fin
8. The distal end should preferably be tapered to facilitate
insertion. The catheter hub and fin are molded as an integral unit
of a plastic such as acrylonitrile-butadiene-styrene, polypropylene
or equivalent plastics. The catheter hub 10 is formed in a tiered
arrangement with sections of smaller and larger diameter. Referring
to FIG. 12, a connection section 38 of smallest diameter is seen to
form a connection between catheter hub 10 and catheter 6. At this
connection section 38 the catheter and catheter hub may be joined
by any suitable method. For example, the said hub can be molded
around the catheter end to form a weld or a solvent may be used to
tackify the plastic and form a bond. A tapering section 40 is
provided adjacent the connection section 38 of small diameter.
Tapering section 40 tapers both internally and externally. Large
section 42 is also provided with a slight internal taper to engage
and guide another section of the needle hub 14. A flange or luer
lock 45 is provided at the proximal end of the catheter hub 10,
which flange serves to facilitate connection with administration
equipment, not shown.
The needle 12, needle hub 14, and needle thumb tab 16 are shown in
FIGS. 6, 10, and 11. The needle 12 is a hollow metal needle of
conventional construction which may be formed of stainless steel or
equivalent materials. At the distal end of needle 12 a needle point
24 is provided with a beveled or lancet point having any suitable
geometry, e.g. an oval or diamond shape, in the plane of the bevel.
At the proximal end of the needle 12 a needle hub 14 is provided
which may be formed of molded plastic and attached to the needle
junction at 46 with an epoxy resin in a conventional manner, or by
swagging or welding. The needle thumb tab 16 is molded in one piece
with the needle hub. Following junction 46 is enlarged section 48
of needle hub 14 which engages inside luer taper 42 of catheter hub
10. Following enlarged section 48 of needle hub 14 is flange 50
molded integrally with needle hub 14 and thumb tab 16 and which
keeps the needle assembly centered in shield 2.
The shield 2 is shown in FIGS. 8 and 9. FIG. 9 shows that the
shield 2 is a tubular hollow element with a series of slots 52 of
varying width as explained with reference to FIG. 2, extending
through substantially all of the shield length. The series of slots
52 extends along an axis parallel to the axial axis of the shield
2. The tubular shield may be molded or extruded using plastics such
as polyethylene, propionate, polypropylene or equivalent materials.
The slots may be formed by stamping out the extruded tube or molded
directly into a molded tube. When the slots are stamped out the
resiliency of the plastic forces the tube to the position of FIGS.
2 and 8. Turning to FIG. 8 a top view of the shield showing the
varying width of the slots is illustrated. Small slot 26 extends
through about half the length of the shield and ends in first
tapered neck 27 which neck leads to intermediate slot 28.
Intermediate slot 28 communicates with a pair of squared shoulders
of first large slot 29, and slot 29 communicates through another
pair of squared shoulders with second large slot 31 through second
tapered neck 30. Next, third tapered neck 32 connects with third
large slot 33. In the distal end the natural resiliency of the
plastic must be utilized to close the shield.
The purpose of the slots has been described above, but a general
review of the manner of using the novel catheter assembly is
considered warranted. The entire assembly which may be packaged in
a sealed envelope to insure sterility during shipment is initially
received in the assembled relationship shown in FIGS. 1 and 2. Upon
removing the outer protective envelope, the device is prepared for
venipuncture by pushing the needle thumb tab 16 with the thumb
forward. This forces needle thumb tab 16 past retaining third
tapered neck 32 and into second large slot 31. Now needle thumb tab
16 is grasped and moved forward to the dotted line shown in FIG. 1.
In this position the needle thumb tab 16 is engaged in first large
slot 29. Since said tab 16, needle hub 14, and flange 50 are molded
in a single piece, the entire needle with appurtenances is thereby
moved forward and a further portion of the needle extends through
end plug 4. Additionally, since the needle and appurtenances are
engaged with the catheter and catheter appurtenances the described
movement of the needle simultaneously moves the catheter and
catheter hub forward until the catheter fin is positioned, as shown
in dotted lines in FIG. 1, in intermediate slot 28. Now the needle
is inserted into a vein thereby simultaneously inserting the
concentric catheter. Venipuncture is accomplished by gripping the
entire assembly and pushing the extending needle and catheter
through the skin into the vein. Now the catheter can be moved
relative to the needle and shield while the needle remains
stationary in the shield by pushing the catheter fin 8 forward.
Continued movement of the catheter pushes out end plug 4 when
catheter hub 10 abuts said end plug, thereby allowing the catheter
8 and catheter hub 10 to be completely removed from engagement with
the needle 12 and shield 2. Since the end plug 4 falls away, the
catheter is entirely free and can be taped to the skin and
connected to administration equipment. As seen in FIG. 7, the fin 8
lies on the skin and tape is applied to the skin across said
fin.
While certain illustrative terms have been used in describing this
invention, no limitation is to be implied from the terminology or
examples given herein.
* * * * *