U.S. patent number 3,906,946 [Application Number 05/440,134] was granted by the patent office on 1975-09-23 for indwelling vein catheter with concentric puncture needle.
This patent grant is currently assigned to Boehringer Ingelheim GmbH. Invention is credited to Cai Gustav Rabbe Nordstrom.
United States Patent |
3,906,946 |
Nordstrom |
September 23, 1975 |
Indwelling vein catheter with concentric puncture needle
Abstract
An indwelling vein catheter assembly with concentric puncture
needle and wing-like, laterally extending, flexible elements
tangentially attached to the catheter body; these wing-like
elements can be folded around the catheter body to form angularly
offset gripping and guide means which assume safe and smooth
insertion of the catheter into a vein, and in the unfolded position
provide support and steadying means for the inserted catheter.
Inventors: |
Nordstrom; Cai Gustav Rabbe
(Mainz, Rhine, DT) |
Assignee: |
Boehringer Ingelheim GmbH
(Ingelheim am Rhein, DT)
|
Family
ID: |
5871183 |
Appl.
No.: |
05/440,134 |
Filed: |
February 5, 1974 |
Foreign Application Priority Data
Current U.S.
Class: |
604/165.03;
604/177 |
Current CPC
Class: |
A61M
25/0637 (20130101); A61M 5/158 (20130101) |
Current International
Class: |
A61M
25/06 (20060101); A61M 5/158 (20060101); A61M
5/14 (20060101); A61M 005/00 () |
Field of
Search: |
;128/214.4,221,348,DIG.16 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Truluck; Dalton L.
Attorney, Agent or Firm: Hammond & Littell
Claims
I claim:
1. An indwelling vein catheter assembly comprising a catheter
fitting, a catheter attached to and extending forwardly from said
catheter fitting, a puncture needle holder attached to the rearward
end of said catheter fitting, a puncture needle extending forwardly
from said needle holder and concentrically through said catheter
fitting and said catheter, and flexible, laterally extending wing
elements attached to said catheter fitting, each of said wing
elements comprising a relatively thick portion at the end thereof
away from said catheter fitting and said relatively thick portion
of said wing elements tapering off into a relatively thin portion,
each of said thin portions being tangentially joined to the
underside of said catheter fitting, said wing elements being
adapted for symmetrically folding around opposite sides of said
catheter fitting with said relatively thin portions snugly folded
around said catheter fitting and with said relatively thick
portions forming a gripping means for guiding said catheter
assembly during insertion into a vein; said gripping means being in
a plane which is at an angle of 30.degree. to 60.degree. with
respect to a plane defined by the longitudinal axis of the puncture
needle and the point of the puncture needle; and said thin portions
being tangentially joined to the underside of said catheter fitting
at a point which is substantially diametrically opposite to said
thick portions of said wing elements when said wing elements are
symmetrically folded around opposite sides of said catheter
fitting.
2. An indwelling vein catheter assembly comprising a catheter
fitting, a catheter attached to and extending forwardly from said
catheter fitting, a puncture needle holder attached to the rearward
end of said catheter fitting, a puncture needle extending forwardly
from said needle holder and concentrically through said catheter
fitting and said catheter, and flexible, laterally extending wing
elements attached to said catheter fitting, said wing elements
being adapted for folding around opposite sides of said catheter
fitting to form gripping means for guiding said catheter assembly
during insertion into a vein, said wing elements being tangentially
attached to said catheter fitting and, in a symmetrically folded
position about the catheter fitting, form said gripping means in a
plane which is at an angle of 30.degree. to 60.degree. with respect
to a plane defined by the longitudinal axis of the puncture needle
and the point of the puncture needle, and a support means laterally
extending from said puncture needle holder, whereby said wing
elements will be supported by said support means during
insertion.
3. An indwelling vein catheter assembly comprising a catheter
fitting, a catheter attached to and extending forwardly from said
catheter fitting, a puncture needle holder attached to the rearward
end of said catheter fitting, a puncture needle extending forwardly
from said needle holder and concentrically through said catheter
fitting and said catheter, flexible, laterally extending wing
elements attached to said catheter fitting, said wing elements
being adapted for folding around opposite sides of said catheter
fitting to form gripping means for guiding said catheter assembly
during insertion into a vein, said wing elements being tangentially
attached to said catheter fitting and, in a symmetrically folded
position about the catheter fitting, form said gripping means in a
plane which is at an angle of 30.degree. to 60.degree. with respect
to a plane defined by the longitudinal axis of the puncture needle
and the point of the puncture needle, and a rigid fixed wing
element laterally extending from said puncture needle holder in a
plane which is at an angle of 30.degree. to 60.degree. with respect
to said plane defined by the puncture needle axis and the puncture
needle point.
4. An indwelling vein catheter assembly according to claim 3,
wherein said catheter fitting and said needle holder are rigidly
connected by releasable locking means.
5. An indwelling vein catheter assembly according to claim 3,
additionally comprising an infusion hose fitting attached to the
rearward end of said needle holder at an angle with respect to the
longitudinal axis of the puncture needle.
Description
This invention relates to a novel indwelling vein catheter assembly
structure.
More particularly, the present invention relates to a novel
indwelling vein catheter assembly with concentric puncture needle
and wing-like, laterally extending, flexible elements tangentially
attached to the catheter body; these wing-like elements can be
folded around the catheter body to form angularly offset gripping
and guide means which assume safe and smooth insertion of the
catheter into a vein, and in the unfolded position provide support
and steadying means for the inserted catheter.
BACKGROUND OF THE INVENTION AND THE STATE OF THE ART
In principle, there are two different techniques by which a
flexible catheter can be inserted into a vein, namely
A. by means of a hollow puncture needle which carries the catheter
in its interior space; or
B. by means of a puncture needle arranged concentrically within the
catheter.
The advantages and disadvantages of these two principles or
techniques are discussed, for example, in column 1 of German Patent
No. 1,566,588, as well as on page 2 of German Offenlegungsschrift
No. 1,491,693. In order to overcome or remedy the disadvantages of
the second technique, various improvements in vein catheters with a
concentric internal puncture needle have been proposed.
For instance, German Offenlegungsschrift No. 1,929,050 discloses a
vein catheter with internal puncture needle, where the catheter is
provided with a flexible wing arrangement at the end opposite to
the point of the puncture needle. This known wing arrangement has
the purpose of not only facilitating the positioning of the
catheter in the vein, but also to improve the flexibility and
adhesion adjacent to the point of puncture (see pages 4 and 5).
These improved effects are achieved by virtue of the fact that,
after insertion of the catheter into the vein, the wings can be
caused to form a kind of "roof" (see page 20, FIG. 8) which
provides a steady support.
Furthermore, German Offenlegungsschrift No. 2,116,108 discloses a
vein catheter with concentric internal puncture needle, where the
catheter is composed of a plurality of telescoping concentric tubes
having successively larger diameters; the center tube includes
integral flexible flaps which extend laterally outward in
substantially opposite directions, and the hollow rearward tube
section envelops a unitary fitting. The flaps, when folded against
each other, serve as auxiliary means to facilitate the introduction
of the catheter into the vein; when allowed to extend apart, the
flaps serve as means for fixing the position of the inserted
catheter.
Catheters of this type, however, have substantial disadvantages or
shortcomings. In conjunction with a vein puncture for insertion of
a catheter, it is always necessary to perforate the human skin.
However, the skin offers a widely varying degree of resistance to
puncture, depending on age, occupation, exposure to sunlight,
location of the puncture, etc. The resistance which must be
overcome in order to perforate the skin is often compared with the
force that is necessary to perforate a thick piece of leather.
The catheter assembly described in German Offenlegungsschrift No.
2,116,108 does not include any means which would, under these
circumstances, prevent the point of the puncture needle from being
forced coaxially into the surrounding catheter during perforation
of the skin. As indicated above, it is necessary to exert a
considerable force in order to perforate the skin. If this force is
applied to the two flaps of the catheter assembly described in the
German publication in an attempt to puncture the skin and insert
the catheter into a vein, the result can only be that the puncture
needle is forced into the catheter wall and toward the rear, so
that no puncture of the vein is possible.
The cone which is supposed to fix the position of the catheter with
respect to the puncture needle in the device of the German
publication can, moreover, not be forced into the counterpart so
firmly that a vein puncture would become possible, because such a
firmly seated cone can scarcely be loosened after the vein puncture
has been effected without moving the very sharp point of the
puncture needle then located in the vein lumen. Every movement of
the needle in this phase of the procedure represents a considerable
risk of injury to the wall of the vein, and an accidental
perforation of the wall results in undesirable perivascular
hemorrhages and at the same time makes the application of an
infusion at this point more complicated.
Finally, it is also not possible to render the catheter assembly of
German Offenlegungsschrift functionally more operative by fixing
the location of the puncture needle with respect to the catheter by
means of a so-called rotatable Luer-Lok (registered tradmark)
closure, because the needle is eccentrically positioned in the
cone, so that no rotary motions are possible.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide an improved
structure for vein catheter assemblies comprising a catheter with a
concentric puncture needle, which enables the user to effect the
vein puncture with significantly greater assurance and safety.
Another object of the present invention is to provide an improved
vein catheter assembly which substantially reduces the chances of
accidental perforation of wall of the vein after introduction of
the catheter.
Still other objects and advantages of the invention will become
apparent as the description thereof proceeds.
THE INVENTION
I have discovered that the above objects are achieved by changing
the structure and location of the wing-like or flap elements of the
prior art devices (hereinafter referred to as "wings" for short),
which serve as holding means for the inserted catheter and as
auxiliary gripping means during insertion of the catheter.
More particularly, I have discovered that the handling and
manipulation of indwelling vein catheters with a concentric
perforating needle can be facilitated and made safer by arranging
the wings on the catheter assembly in such a way that they can be
folded together around the outside of the body of the catheter
assembly at the end opposite to the point of the puncture needle,
so as to form gripping means for use during the perforating and
insertion procedure; after the catheter has been inserted and
properly seated in the vein, the wings are unfolded again and then
come to be flat against the skin area adjacent to the point of
puncture and thereby form support means for the catheter so as to
help prevent it from moving. In contradistinction from the prior
art structure, the wings in accordance with the present invention
are not arranged symmetrically with respect to a plane defined by
the longitudinal axis of the puncture needle and a line passing
from the eccentric point of the puncture needle parallel to the
longitudinal axis to the rear thereof, but rather in such a way
that, when folded together during the puncture and insertion phase,
they form an angle of about 30.degree. to 60.degree. with the said
plane. This particular angle is fixed by a Luer-Lok closure located
between the catheter fitting and the cannula carrier.
The attached drawings show the improved structure of the catheter
assembly according to the present invention. In these drawings
FIG. 1 is a cross-sectional view of the catheter assembly along a
plane passing between the wings in the folded state (plane E-F in
FIG. 3).
FIG. 2 is a rear view of the catheter assembly with the wings in
the unfolded position.
FIG. 3 is a rear view of the catheter assembly with the wings in
the folded position.
FIG. 4 is a partial cross-sectional top view of the catheter
assembly with the flexible wings in the unfolded position and the
connecting hose for the infusion device attached.
FIG. 5 is a perspective view of the catheter assembly.
FIG. 6 is a detailed view of X of FIG. 5.
In all these figures like reference numerals identify like parts of
the catheter assembly. Thus, 1 identifies the internal puncture
needle, 2 is the catheter telescopically carried by the puncture
needle, 3 is the catheter fitting, 4 is the puncture needle holder
with Luer-Lok cone, 5 is an inclined stud for the rear closure cap,
6 is the closure cap, 7 is a fixed wing against which the flexible
wings are folded, 8 are the flexible wing elements, 9 is the
protective cap for the puncture needle when the device is not in
use, 10 is the connecting hose for the infusion device, 12 are the
connecting portions between the wing elements 8 and the body of the
catheter assembly, and 13 are the gripping portions of the wing
elements 8.
FIG. 1 shows particularly clearly the fixed connection between the
catheter and the concentric puncture needle formed by the Luer-Lok
cone, as well as the angle .alpha..sub.1 (about 45.degree. )
between the longitudinal axis of the catheter assembly and the
inclined closure stud 5.
FIG. 2 shows the relative position of the two wing elements in the
unfolded position, the fixed wing 7, and the closure stud 5.
FIG. 3 shows how the wing elements 8 are folded around the body of
the catheter assembly and against the fixed wing 7 during the
puncture and insertion procedure.
FIG. 4 also illustrates the connection between the puncture needle
holder and the catheter fitting, as well as the position of the
unfolded flexible wings in relation to the catheter assembly
body.
FIG. 5 shows the plane passing through the puncture needle axis and
the point of the puncture needle (identified by letters ABCD) and
the angle .alpha..sub.2 (here about 45.degree.) between said plane
and the wings in the folded position. It also shows the flexible
wings in the folded and unfolded positions, as well as how the
wings fold around the needle holder 4. Finally, it also shows the
relatively thin portion 12 and the relatively thick portion 13 of
one of the wing elements.
FIG. 6 shows how the plane ABCD passes through the longitudinal
axis of the puncture needle and also contains the line which
extends from the point of the puncture needle rearwardly.
The catheter fitting 3 as well as the two wings 8 extending
therefrom are advantageously made of flexible plastic material. The
wings are preferably connected with or fastened to the catheter
fitting tangentially, that is, over a very small area, so as to
avoid the formation of lumps and ridges at the point of juncture
and thereby assure a smooth contact area with the skin. The wings
may also be fastened to the underside of the catheter fitting by
means of small hinges. It is most advantageous to fashion the wings
in such a way that the outer, relatively thick portions (13)
thereof which form the gripping means in the folded position taper
off into relatively thin portions (12) which are tangentially
joined to the catheter fitting. The length of the tapered thin
portion may be different for each wing element, especially if the
angle .alpha..sub.2 is to be about 30.degree. to 60.degree. and if,
additionally, a rotation of the inserted catheter in the vein lumen
is to be avoided. The thin, tapered section for each wing should be
so designed that when the thicker end portions of the wings are
folded together the thin portions snugly fit around the catheter
fitting. For this purpose the thick portion of the wings tapers off
in concave fashion to follow the contour of the catheter fitting
(see FIG. 5), so that when the thick portions of the wings are
folded together, the thin portions form a continuous, virtually
seamless surface with the outside of the needle holder 4. The thin
portions are tangentially joined to the underside of the catheter
fitting at a point which is substantially diametrically opposite to
the thick portions of the wing elements when the wing elements are
symmetrically folded around opposite sides of the catheter
fitting.
The above-described structure of the wings has the important
advantage that they not only provide in the unfolded position firm
support means for the inserted catheter, as in the prior art
structure, but in the folded position also provide auxiliary
insertion guide means which are much superior to analogous prior
art structures. By virtue of the inclination of the gripping means
formed by the folded wings with respect to plane ABCD and thus the
point of the insertion needle (angle .alpha..sub.2), a
physiologically correct position of the manipulator's hand is
provided, whereby the adroitness of the insertion of the catheter
and the precision of the vein puncture is materially increased. At
the same time the risk of an accidental perforation of the vein
wall adjacent or opposite to the point of catheter insertion and
consequential hemorrhages in the adjacent tissue is avoided.
In the case of catheter assemblies which incorporate the prior art
wing structure, on the other hand, that is, where the wings are
arranged symmetrically with respect to the plane above referred to,
there is great danger of accidental vein perforation during the
insertion procedure because, if the manipulator is a right-handed
person, the point of the insertion needle unavoidably drifts to the
left, and in the case of a left-handed person to the right. This
needle drift cannot be observed or corrected, however, since the
insertion needle is invisible beyond the point of insertion.
Moreover, the wings are in a physiologically unfavorable position,
which makes the insertion of the catheter into the vein more
difficult.
In contrast thereto, if the wings in the folded position are
inclined with respect to plane ABCD by an angle of about 30.degree.
to 60.degree., preferably 45.degree., as in accordance with the
structure of the present invention, this needle drift is
compensated and the needle follows the desired path along the
middle of the vein lumen.
Another advantageous embodiment of the catheter assembly pursuant
to the present invention provides, in addition to the two flexible
wings 8, another unilateral, rigid wing extension 7 which is
preferably made of hard plastic and is rigidly attached to or made
a unitary part of needle holder 4, and is inclined with respect to
plane ABCD by angle .alpha..sub.2. When the flexible wing elements
are folded together in this embodiment, their outer portions 13
come to lie flat against the sides of the rigid wing extension 7,
as shown in FIG. 3, so as to form gripping and guide means which
can be held between the thumb and forefinger of the manipulator
during the insertion procedure. Once the catheter has been inserted
into the vein and the flexible wings have been unfolded against the
adjacent skin area to form the supporting and securing means, one
hand can be used to withdraw the puncture needle by means of the
rigid wing extension without changing the position of the catheter
within the vein, while the other hand can be used to press the
unfolded flexible wing elements against the skin of the patient. In
this embodiment, where the folded flexible wings and the rigid wing
extension together stand at an angle of 30.degree. to 60.degree.,
preferably 45.degree., with respect to plane ABCD during the
insertion procedure, it is also advantageous to provide a solid
connection between the catheter and the rear end of the puncture
needle through the needle holder, for instance by means of a
locking cone (Luer-Lok cone). This arrangement substantially
facilitates a smooth and safe insertion of the catheter into the
vein, because the two components are thereby joined into a single
unit and the angle .alpha..sub.2 of about 45.degree. is fixed. By
virtue of the locking connection the catheter and its flexible
wings are brought into a symmetrical position with respect to the
rigid wing extension (see FIGS. 2 and 3), so that the flexible
wings can be folded around the catheter fitting and snugly against
opposing surfaces of the rigid wing extension. The rotation of the
puncture needle in the locking cone after insertion of the catheter
into the vein is a simple procedure and can readily precede the
above-described withdrawal of the puncture needle from the
catheter.
Since in most cases a vein extends substantially parallel to the
skin surface, it is additionally of advantage to assure easy
handling if the catheter is flat on the bottom and can thus be
inserted virtually parallel to the skin. This feature can be
achieved by attaching the closure stud 5 at an angle of about
30.degree. to the needle holder 4 (see angle .alpha..sub.1, in FIG.
1) and having its longitudinal axis coincide with plane ABCD (see
FIG. 3).
Finally, it is further advantageous, for the purpose of connecting
the vessel containing the infusion liquid, to interpose between the
said vessel and the catheter a hose which is made of considerably
softer plastic or rubber than the catheter itself, instead of
connecting the infusion device directly to the catheter. By virtue
of this arrangement no pushing or pulling motions are transmitted
to the inserted catheter, which means greater safety and provides
for secure indwelling of the catheter in the desired position
within the vein lumen. For reasons of safety it is highly desirable
if the flexible, soft hose is rigidly connected by means of the
locking cone (Luer-Lok cone).
While the present invention has been illustrated with the aid of
certain specific embodiments thereof, it will be readily apparent
to others skilled in the art that the invention is not limited to
these particular embodiments, and that various changes and
modifications may be made without departing from the spirit of the
invention or the scope of the appended claims.
* * * * *