U.S. patent number 3,831,814 [Application Number 04/844,946] was granted by the patent office on 1974-08-27 for trocar-cannula.
This patent grant is currently assigned to Cutter Laboratories, Inc.. Invention is credited to William F. Butler.
United States Patent |
3,831,814 |
Butler |
August 27, 1974 |
TROCAR-CANNULA
Abstract
A trocar-cannula for piercing a venoclysis diaphragm. A piercing
point is provided on the end of a trocar, providing three large
openings for passage of fluid into the interior of the cannula
tube, as defined by three ribs shaped to provide maximum size of
openings, to minimize cutting or tearing action on the diaphragm,
to maximize stretching action thereon, and to prevent possible
collapse of part of the container from closing off the opening
area. Also, a combination trocar-cannula-drip barrel unit is
shown.
Inventors: |
Butler; William F. (Oakland,
CA) |
Assignee: |
Cutter Laboratories, Inc.
(Berkeley, CA)
|
Family
ID: |
25294028 |
Appl.
No.: |
04/844,946 |
Filed: |
July 25, 1969 |
Current U.S.
Class: |
222/81; 604/274;
604/411 |
Current CPC
Class: |
A61M
5/162 (20130101) |
Current International
Class: |
A61M
5/162 (20060101); A61M 5/14 (20060101); G07f
011/00 () |
Field of
Search: |
;222/81-90,159
;128/214C,347-351,221 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Knowles; Allen N.
Attorney, Agent or Firm: Owen, Wickersham & Erickson
Claims
I claim:
1. A trocar-cannula for piercing a venoclysis diaphragm of a
fluid-containing container, comprising,
a cylindrical tube portion with an integral trocar on one end, said
trocar comprising
a rounded point-like extremity for piercing a venoclysis diaphragm
with a minimum of cutting action,
three ribs joining said extremity smoothly to said tube, said ribs
having smooth outer surfaces free from sharp edges,
said trocar having three openings, one opening between each two
adjacent ribs,
whereby after piercing a said diaphragm, said trocar stretches it
and said fluid passes into said tube through the three openings,
the threefold nature acting to prevent collapse of said container
on more than one said opening and acting to provide the maximum
size opening at all times consonant with the needed strength.
2. The trocar-cannula of claim 1 wherein said trocar tip is
generally pyramidal.
3. The trocar-cannula of claim 2 wherein said openings are
generally triangular.
4. The trocar-cannula of claim 2 wherein said openings are
generally elliptical.
5. The trocar-cannula of claim 1 wherein said trocar ribs are
generally radial with nearly radial sidewalls meeting their outer
surfaces at rounded edges.
6. The trocar-cannula of claim 5 wherein said openings are
generally lozenge-shaped.
7. The trocar-cannula of claim 5 wherein said openings are
generally triangular.
8. A trocar-cannula for piercing a venoclysis diaphragm of a
fluid-containing container, comprising,
a cylindrical tube portion with an integral trocar on one end, said
trocar comprising
a rounded point-like extremity for piercing a venoclysis diaphragm
with a minimum of cutting action,
three narrow generally radial ribs joining said extremity smoothly
to said tube, said ribs having nearly radial sidewalls and smooth
outer surfaces inscribable in a three sided pyramid and with
rounded edges,
said tube being recessed from where said ribs meet it to describe
three generally triangular cylindrical shell segments with
sidewalls generally perpendicular to the outer surface of said
tube, the sidewalls of each said recesses being joined by a face
sloping from the inner to the outer surface of the tube,
thereby providing three generally lozenge-shaped large
openings,
whereby after piercing a said diaphragm, said trocar stretches it
and fluid from said container passes into said tube through the
three lozenge-shaped openings, the threefold nature acting to
prevent collapse of said container on more than one said opening
and acting to provide the maximum size openings at all times
consonant with the needed strength, the walls of the opening being
so shaped as to minimize cutting or tearing action.
9. A trocar-cannula for piercing a venoclysis diaphragm to enable
passage of fluid therethrough, comprising,
a cylindrical tube having spaced from one end a disc-like flange,
said tube on the opposite side from said end narrowing to a smaller
exterior diameter while maintaining the same inner diameter,
and,
a trocar integral with said tube on the end of the smaller diameter
portion, said trocar comprising
a rounded point-like extremity for piercing a venoclysis diaphragm
with a minimum of cutting action,
three narrow radial ribs joining said extremity smoothly to said
tube, each of said ribs having nearly radial sidewalls generally
parallel to the radial plane through the center of the rib, and
outer surfaces inscribable in a cone, meeting said sidewalls at
rounded edges,
said tube being recessed on each side from where said ribs meet it
to describe three triangular cylindrical-shell segments, each with
two sidewalls each perpendicular to planes perpendicular to the
radial plane through the rib which it joins, the two sidewalls
being joined by a face with a sloping surface, sloping away from
said extremity from the inner to the outer surface of the tube,
thereby providing between said ribs and said shell segments three
large generally lozenge-shaped openings,
whereby after its extremity pierces a said diaphragm, said trocar
ribs stretch it and said fluid passes into said tube through the
three lozenge-shaped openings.
Description
This invention relates to a novel trocar-cannula for piercing a
venoclysis diaphragm.
Now that venoclysis diaphragms are made from plastic, it has become
important to prevent the point which cuts through them from tearing
or cutting the diaphragm to a point where there is leakage around
the cannula. It has also become important to prevent closure of the
area of the openings into the cannula, by collapse of the wall of
the container. Furthermore, it is important to obtain maximum
delivery for any given diameter of cannula.
All these objectives are simply stated, but are not so easily
achieved. However, these problems are solved by the apparatus of
this invention, which employs a trocar with a generally rounded
extremity serving as the "point" for piercing and with three
openings defined by three ribs and recessed end portions of the
tube, with the rib walls rounded and shaped to provide narrow areas
of contact while at the same time avoiding any cutting edges. These
features that solve the problem are all absent from the prior art
devices, where reliance was made on sharp edges with cutting
functions and where insufficient attention was given to the dangers
that might be produced by collapse of the wall of the container or
by insufficient feed of fluid.
Other objects and advantages of the invention will appear from the
following description of a preferred form thereof.
In the drawings:
FIG. 1 is an enlarged head-on view of a trocar-cannula embodying
the principles of the invention.
FIG. 2 is a view in section taken along the line 2--2 in FIG.
1.
FIG. 3 is a fragmentary view in elevation of the end portion of the
trocar-cannula as viewed along the arrows 3--3 in FIG. 2.
FIG. 4 is a fragmentary view in elevation and partly in section on
a somewhat reduced scale showing how the trocar-cannula of FIGS.
1-3 is used to pierce a venoclysis diaphragm, broken lines showing
the position after piercing.
FIG. 5 is a view similar to FIG. 1 of a modified form of
trocar-cannula also embodying the principles of the invention.
FIG. 6 is a view similar to FIG. 3 of the trocar-cannula of FIG.
5.
FIG. 7 is a view in section taken along the line 7--7 in FIG.
6.
FIG. 8 is a view similar to FIGS. 1 and 5 of another modified form
of trocar-cannula, also embodying the principles of the
invention.
FIG. 9 is a view similar to FIGS. 3 and 6 of the trocar-cannula of
FIG. 8.
FIG. 10 is a view in section taken along the line 10--10 in FIG.
9.
FIG. 11 is a view in elevation and in section of a combination
trocar-cannula-drip barrel unit, also embodying the principles of
the invention.
FIGS. 1-3 show a trocar-cannula 10 that embodies the principles of
the invention, having a trocar 11 at one end and a cylindrical
cannula tube 12 at the other end. Spaced from the end 13 of the
cannula 12 is a disc-like flange 14, against which a flexible tube
or conduit shown in broken lines in FIG. 4 may be pushed,
encircling the cannula 12 and conveying liquid therefrom. On the
other side of the disc flange 14, the exterior diameter of the
cannula tube 12 is narrowed at an exteriorly sloping portion 16,
while the interior diameter remains the same, thereby providing a
thinner and narrower wall portion 17 where less strength is needed.
This thinner wall portion 17 is integrally joined to the trocar or
three-segmented portion 11.
At the end of the trocar 11 is a rounded point-like extremity 20
which serves to pierce the venoclysis diaphragm 21 (FIG. 4), but,
due to its rounded shape, does this with a minimum of cutting or
tearing action, though there is, of course, some cutting. Three
narrow radial ribs 22, 23, 24 join this extremity 20 smoothly to
the tube portion 17. The ribs 22, 23, 24 are made as narrow as is
feasible, but their outer surfaces and edges are rounded so as to
prevent any cutting action, as would occur from a sharp edge; as a
result movement of the trocar 11 into the diaphragm 21, after
piercing by the extremity 20, results mostly in spreading and
stretching the diaphragm wall rather than tearing or cutting it, so
that when the trocar 11 is fully inserted (FIG. 4) the diaphragm
wall ends up encircling the tubular portion 17, going, of course,
no further than the flange.
The sidewalls 25, 26 of the ribs 22, 23, 24 are generally radial
and are perhaps better described as parallel to the radial plane
which bisects their ribs 22, 23, 24 so that each rib 22, 23, 24 is
generally rectangular in cross-section, except for the interior
wall 27 which may be slightly concave. Again, the edges are rounded
and not sharp.
Moreover, the end of the tubular portion 17 is itself cut back by
three recesses 28, 29, 30 with converging walls 31, 32, and again
the side walls 31, 32 of these recesses 28, 29, 30 lie generally
radially, so that they are perpendicular to all planes
perpendicular to the radial plane through the ribs 22, 23, 24. The
walls 31, 32, in each recess converge but do not meet at a sharp
point, but rather meet at a short cylindrical arc 33, on the
interior surface, whice is joined to the exterior surface by a
smooth bevel or sloping face 34.
As a result, three large openings (shown in FIGS. 1-4 as generally
lozenge-shaped) are provided with approximately the maximum size of
opening that can be obtained while still getting the strength
necessary for entry of the trocar 11 into the diaphragm.
Due to the three-fold nature of the structure, collapse of the
walls 35 of the venoclysis bag 36 (FIG. 4) against the device 10 is
not able to block off the full area of the openings as they might,
for example, if there were only two such openings diametrically
opposite each other. At the most, one of these openings could be
blocked off, and the blocking off of one would insure that the
other two would be rather wide-open.
In using the trocar-cannula 10, the extremity 20 is forced through
the diaphragm 21. Instead of the extremity 20 beginning a cutting
action that is carried out by sharp ribs, along with tearing, the
cutting action stops just beyond the rounded extremity 20 itself,
and the remaining action of the rounded ribs 22, 23, 24 is a
stretching action, which minimizes tear, and therefore minimizes
leakage around the cannula.
FIGS. 5, 6, and 7 show a modified form of the invention differing
principally in the shape of the openings through the trocar. Most
of the parts of the device are the same, but here a trocar 40 is
provided with ribs 41, 42, and 43 and with openings 44, 45, and 46
which are generally in the form of a three-sided pyramid. Thus, the
shape of the trocar 40 is, in this instance, generally that of a
pyramid, with the outer ribs 41, 42, and 43 providing smooth
surfaces but with the openings 44, 45, 46 extending directly into
the pyramid face instead of being formed in the manner shown in
FIGS. 1 through 4.
FIGS. 8 through 10 show a trocar 50 that is generally similar to
the trocar 40 of FIGS. 5 through 7, except that the openings are
generally elliptical or circular, depending on the way in which
they are viewed. Thus, there are ribs 51, 52, and 53 with
elliptical openings 54, 55, and 56.
FIG. 11 shows how the principles of the invention can be used to
make a combination trocar-cannula-drip barrel 60. The trocar itself
is substantially identical to that shown in FIGS. 1-4 but instead
of merely terminating in the end 13 of the tube 12, it terminates
in a drip barrel 61. The drip barrel 61 empties into a filter unit
62. The unit 60 itself may be made of transparent plastic with a
flexible housing 63. This complete combination unit 60 enables the
user to dispense with the separate units and the connections
heretofore that had to be used between them.
To those skilled in the art to which this invention relates, many
changes in construction and widely differing embodiments and
applications of the invention will suggest themselves without
departing from the spirit and scope of the invention. The
disclosures and the description herein are purely illustrative and
are not intended to be in any sense limiting.
* * * * *