Note: Descriptions are shown in the official language in which they were submitted.
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STAPLE AND STAPLE APPLICATOR FOR USE IN
SKIN FIXATION OF CATHETERS
BACKGROUND OF THE INVENTION
This invention relates to medical staples and stapling devices. More
particularly, the invention relates to a staple in combination with a
flexible, digitally
manipulable, anvilless staple applicator that is useful for affixing catheters
to the skin and for
other medical procedures.
Medical stapling devices have been routinely in use for some time. They are
designed chiefly to replace the suturing process because of the significantly
less time used in
stapling. A variety of devices are known. For example, Green, U.S. Patent No.
5,158,567,
describes an anvilless surgical stapler with articulated handles and a
slidable staple cartridge
mounted in a block at the distal end of the handles. Samuels, U.S. Patent No.
4,399,810,
describes a skin clip applied with an articulating device containing a
substantial number of
staples. The staples are closed by a lateral pressure from the articulating
applier. U.S. Patent
Nos. 4,719,917 and 4,526,174 disclose other medical staples.
In surgical and anesthetic practice, it is common to place indwelling
catheters
for vascular access. These catheters require fixation to the skin to maintain
their position,
thus avoiding potential injury to the patient or withdrawal of the catheter.
Currently, fixation
to the skin is accomplished by suturing the catheter hub to the underlying
skin. A needle and
suture are passed through the skin and hub eye, or eyes, and tied into a knot.
This procedure includes an attendant risk of needle stick. To avoid that risk
would require the use of a stapler kit, which is far too costly to justify its
use for one or two
staples. The use of a stapler would save considerable time over suturing,
especially when
considering the daily frequency of catheter fixations in clinical situations,
but the cost of a
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stapler kit is orders of magnitude greater than that for a suturing kit.
SUMMARY OF THE INVENTION
The present invention allows fixation of catheters to the skin in a less time-
consuming and safer manner than either suturing or the use of traditional
medical staplers.
The cost of the materials is anticipated to be, for practical purposes,
approximately the
equivalent of suturing.
The present invention is a method of stapling and a device for performing that
method. The device comprises an applicator assembly, preferably made of
sterilizable,
medical grade plastic, and is disposable. A staple is fabricated from
stainless steel or other
commonly used FDA approved staple material, and is inserted into the
applicator to form the
assembly. The applicator has no anvil and is both flexible and digitally
manipulable.
The staple includes a crown portion with legs obliquely positioned
at the ends of the crown. The legs terminate in points capable of piercing the
skin. In the preferred embodiment of the invention, a single staple is mounted
in
the applicator.
The applicator is shaped generally like an inverted "U. " with an
open bottom to permit the exiting of a closed staple attached to the skin. The
inner faces of the applicator include a stabilizing channel and grooves that
retain
the staple during both storage and application, and guide it during the
application
process. The outside faces of the two opposing arms of the applicator are
preferably a relatively non-slip surface to facilitate a digital grasp of the
applicator and to permit digital deformation of the applicator, which in turn
deforms the staple.
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In its preferred use, an applicator with staple is positioned to cause one
of the two staple legs to traverse the catheter hub eye and both staple legs
to pierce the
skin when lateral forces are manually applied to the applicator arms. Closure
of the
staple then results in fixation of the catheter to the skin. The applicator
can
subsequently be slid off the staple, which is no longer held by the applicator
due to
the change in staple configuration relative to the released applicator.
In an alternate embodiment, two or more applicator and staple
combinations are joined together to provide a device that can be used when two
or
more staples are necessary.
In accordance with another aspect of the present invention, there is
provided an assembly for applying a single surgical staple, comprising:
a surgical staple configured to have a crown portion with two ends and two
legs disposed at each of said ends, said legs terminating at distal ends with
piercing
points, each of said legs comprising at least two segments disposed angularly
to each
1 S other; and
a flexible, anvilless, digitally manipulable staple applicator with inner and
outer faces,
said applicator being comprised of a backbone and two arms extending
from said backbone and including means for retaining, guiding, and stabilizing
said staple,
whereby said staple is releasably mounted in said retaining, guiding,
and stabilizing means.
In accordance with another aspect of the present invention, there is
provided a dual applicator for holding two surgical staples, each of said
staples having
a crown portion and two legs, said dual applicator comprising:
two anvilless, digitally manipulable staple applicators with inner and outer
faces, each of said applicators being comprised of a backbone and two arm
portions
extending from said backbone,
each of said applicators including means for retaining, guiding, and
stabilizing
one of said staples, in which said one staple is releasably mounted; and,
whereby said dual applicator is formed by joining said two applicators.
In accordance with another aspect of the present invention, there is
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provided an assembly for applying a surgical staple, comprising:
a staple applicator with an exterior and an interior, the applicator including
first and second digitally manipulable arms with inner and outer surfaces, the
first arm
being movable toward the interior of the applicator;
a surgical staple disposed between and operatively connected to the inner
surfaces of the digitally manipulable applicator arms, the staple terminating
with
spaced apart piercing points; and
at least one staple holder associated with the interior of the applicator and
in
which the surgical staple is mounted, whereby digital manipulation of the
first
applicator arm toward the interior of the applicator reduces the space between
the
staple piercing points.
In accordance with another aspect of the present invention, there is
provided an assembly for applying a surgical staple, comprising:
a staple applicator with an exterior and an interior, the applicator including
first and second digitally manipulable arms with inner and outer surfaces, the
first arm
being movable toward the interior of the applicator;
a surgical staple disposed between and operatively connected to the inner
surfaces of the digitally manipulable applicator arms, the staple terminating
with
spaced apart piercing points; and
at least one staple holder associated with the interior of the applicator and
in
which the surgical staple is mounted, whereby digital manipulation of the
first
applicator arm toward the interior of the applicator reduces the space between
the
staple piercing points.
In accordance with another aspect of the present invention, there is
provided an assembly for applying a surgical staple, comprising:
an anvilless staple applicator with an exterior and an interior, the
applicator
including an upper portion connecting two digitally manipulable arms with
inner and
outer surfaces;
a surgical staple disposed in the interior of the applicator and having an
upper
portion and legs terminating with spaced apart piercing points, wherein the
upper
portion of the staple is oriented toward the upper portion of the applicator
and the
staple legs are operatively connected to the inner surfaces of the digitally
manipulable
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applicator arms; and
at least two staple holders associated with the interior of the applicator and
in
which the surgical staple is mounted, whereby digital manipulation of the arms
moves
the staple piercing points toward each other to secure the staple.
In accordance with another aspect of the present invention, there is
provided use of an assembly for applying a surgical staple for fixing a
catheter to skin,
the assembly comprising:
a staple applicator with an exterior and an interior, the applicator including
first and second digitally manipulable arms with inner and outer surfaces, the
first arm
being movable toward the interior of the applicator;
a surgical staple disposed between and operatively connected to the inner
surfaces of the digitally manipulable applicator arms, the staple terminating
with
spaced apart piercing points; and
at least one staple holder associated with the interior of the applicator and
in
which the surgical staple is mounted, whereby digital manipulation of the
first
applicator arm toward the interior of the applicator reduces the space between
the
staple piercing points.
Accordingly, there are several objects and advantages to my invention.
One advantage provides a means for securing a catheter to the skin using a
surgical
staple and applicator in a less time-consuming procedure than suturing.
Another advantage permits securing the catheter to the skin with less
risk of needle stick injury when compared to the traditional method of
suturing.
An object of the invention is to provide a stapler for affixing a catheter
to the skin that is, relative to other staplers, less expensive to
manufacture, easy to
distribute and store in a clinical environment, and is both simple and
reliable to use.
Still another object of the invention is to provide the availability of a
small number of staples when the use of a traditional stapler kit is not
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economical .
These and other objects and advantages will become apparent in
conjunction with the detailed description and the following drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows a surgical staple in the open position.
Figure 2 shows the staple in the closed position.
Figure 3 is a perspective view of a staple applicator and staple.
Figure 4 is a cross section of one embodiment of the applicator
and staple.
Figure 5 is an elevation view of the applicator with the staple in
the open position.
Figure 6 is an elevation view of the applicator containing the
staple in the closed position.
Figure 7 is a perspective view of the applicator and staple adjacent
to, and prior to the clamping of, the skin and hub eye.
Figure 8 is a perspective view of the applicator and staple after
clamping the skin and hub eye.
Figure 9 is an elevation view of the applied staple after the legs of
the applicator have been released.
Figure 10 depicts a standard staple remover, which is part of the
pnor art.
Figure 11 is a cross section of a staple being removed.
Figure 12 is an alternate embodiment of the invention, with two
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applicators joined together.
Figure 13 is a perspective view of the alternate embodiment.
Figure 14 is a perspective view of another alternate embodiment.
Figure 15 is a cross section of one of the tabs in Figure 14.
Figure 16 is yet another embodiment, with deeper grooves.
Figure 17 is another embodiment of the dual applicator assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to Fig. 1, a staple 10 is constructed of stainless
steel, titanium, or other similarly deformable material which retains the
shape to
which it has been deformed. The staple 10 includes a crown portion 20 and
opposingly disposed legs 22. In the preferred embodiment, the crown 20 is
generally horizontal and connected to legs 22 at each end. Legs 22 are
preferably
identical and comprised of three segments, 24, 26, and 28, terminating in skin
piercing point 29. The three leg segments 24, 26; 28 are offset by three
oblique
angles A, B, and C, which are approximately 120 degrees each.
Fig. 2 depicts the staple in its closed, deformed configuration.
After the staple has been completely closed and the applicator withdrawn,
angle
A between crown 20 and leg segment 24 should be approximately a 90 degree
right angle.
Figures 3, 4, and 5 depict an anvilless applicator 30 holding a
staple 10 in the open position. The applicator comprises a top or backbone
portion 32 and two arms 34. The inside face 33 of backbone 32 includes a
stabilizing block 40 with stabilizing channel 42 that prevents the staple from
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rotating about point 25 between leg segments 24 and 26.
The inside faces 35 of the applicator arms 34 contain guidance and
retaining grooves 44 into which staple leg points 25 are slidably and
releasably
mounted. Grooves 44 terminate in a curved portion 46, so that contact between
the staple and the applicator is maintained while the staple is compressed
during
application. The staple should be mounted and retained in the applicator with
a
slight degree of snugness, so the staple does not fall out prior to use. At
the same
time, the staple should be easily releasable from grooves 44 and channel 42
once
the staple has been applied. The outside face of the applicator arms 34
includes a
means for digitally holding and compressing the applicator arms 34. In the
present invention, that means is preferably a series of ribs 52 on each
applicator
arm 34. Other cupped, polygonal, non-uniform, or rough surfaces are equivalent
to the ribs, as those of skill in the art will appreciate.
It should be noted that the present invention comprises a Class I
medical device, e.g., a skin stapler with removable staples and nonabsorbent
legs. Under FDA regulations, a Class I medical device does not require pre-
notification of, or approval from, the FDA. Thus, this invention can be
practiced
with little or no regulatory costs or delays.
Prior to using the present invention, a transcutaneous vascular
catheter is placed in the patient in the usual manner (not shown). Referring
now
to the additional figures, the applicator 30 containing a staple 10 is held
between
the thumb and second finger of the operator's dominant hand. The open staple
points 29 are held away from the operator. The operator's other hand is used
to
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manipulate the catheter hub 60 and underlying skin 62, so the skin 62 is
tented
(see Fig.7) and positioned to receive staple 10. The applicator and staple
assembly is positioned so one staple piercing point 29 traverses the eye 64 of
catheter hub 60 and both points 29 come to rest on the base of the tented
skin.
The tented skin 62 has been manipulated to rest between the open staple legs
22
through a combination of tenting by the non-dominant hand and positioning of
the applicator 30 and staple 10 by the dominant hand.
The staple is closed by squeezing the applicator arms 34 with
one's fingers, which generates a closing force F (see Fig. 8). This causes the
piercing points 29 to penetrate the skin. The medial progress of the
applicator
arms 34 is arrested by the ends of crown 20 at approximately a ninety degree
angle D(see Figs.S and 6). After the applicator arms 34 are released (see Fig.
9),
there is a small, almost imperceptible, spring-like rebound of the staple legs
22.
For practical purposes, the angle between the staple crown 20 and legs 22
remains approximately 90 degrees.
A staple used in the described embodiment must have at least two
leg segments that form an angle whose intersecting point is outside the ends
of
crown portion 20. Such a configuration would be analogous to leg segments
24,26 meeting at point 25, which is outside the end of staple crown 20--a
necessary configuration so that the applicator arms 34 can provide a lateral
force
to secure the staple to the skin. While the preferred embodiment contemplates
a
staple like that shown in Fig. 1, it is possible to employ other, differently
shaped
staples that come within the scope of the patent. Indeed, the applicator and
staple
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could be configured so that the applicator backbone and arms would begin the
application with angle D at approximately 90 degrees.
When the squeezed applicator arms 34 are released, applicator
arms 34 generally regain their original configuration in relation to
applicator
backbone 32. Applicator 30 can then be removed from staple 10, because staple
is no longer held by grooves 44. In the preferred embodiment, it is
contemplated that grooves 44 frictionally hold staple 10 prior to use,
although
only a small force is required to release staple 10 from grooves 44. Here that
force would simply consist of the rebound of plastic applicator arms 34. Also
in
10 the preferred embodiment, stabilizing channel 42 is large enough so that
staple
crown 20 can be loosely contained in the space of channel 42. Thus, in Fig. 9
the
upward force FF required to lift the applicator 30 off staple 10 after use is
simply
the force required to overcome the weight of the applicator 30.
Once the staple is applied, the applicator can be discarded. When
the staple must be removed from the patient, it can be accomplished in a
traditional, prior art manner (see Figs. 10-11) and a dressing applied as
necessary.
For a catheter hub with two eyes, one can approach the problem in
at least two different ways. First, one can use two separate assemblies of a
single
applicator and staple. Alternatively, one can use a second embodiment of the
invention, a dual applicator 100 (Fig. 12) that is made from two separate
assemblies 100A, 100B, with each assembly made of a single staple 110 and
single applicator 130. The assemblies are preferably connected by a plastic
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bridge or joining member 120. The second staple can be applied by rotating the
applicator one hundred eighty degrees with the dominant hand. Thus, a two-eyed
hub can be secured to the skin without setting down the staple applicator. In
a
similar manner, two staples can be used in a situation not requiring a
catheter,
such as for a small wound that would otherwise be closed by suturing.
Another embodiment contemplates three or more staples and
applicators. There are a number of ways to join the applicators. One way would
be to add additional joining members and assemblies in a manner similar to
that
in Fig. 12. The preferred arrangement comprises a series of spoke-like joining
members emanating from a hub or hub-like point 511 (see Fig. 1?) and can be
called the L-shaped or partial "ferns wheel" configuration. Two or more spokes
520, like joining member 120 above, and applicator assemblies 530, can be
added to the device depicted in Fig. 17. In Fig. 17, ribs 552 correspond to
ribs
52 discussed above, and are disposed on the outside face of applicator arms
534.
Another mufti-assembly configuration could contain a substantial
number of staples mounted inside applicators and arranged in a "centipede"
like
strip of 4,10,20,or more assemblies. Each assembly could be joined by a short
connecting piece, like plastic connector or joining member 120 (Fig. 12). Then
the medical care giver could cut off one or two assemblies as necessary.
Numerous other embodiments and uses are contemplated of the
present invention, resulting from the simple geometry underlying the staple
and
staple applicator. As one of ordinary skill in the art can appreciate, grooves
44
and channel 42 function to (1) retain staple 10 in applicator 30 prior to and
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during the use of the invention, (2) guide the staple downward while it is
closing,
and (3) stabilize the staple so that it does not rotate around axis A-A
through
points 25.
Given the nature of the invention, innumerable additional
5 embodiments can be envisioned. Some examples appear in Figures I3-16. In
Fig.
13, stabilizing block 40 and channel 42 of Fig. 3 have been replaced by two
small stabilizing blocks 240 and two corresponding stabilizing channels 242.
Leg
segment intersections 225 (Fig. 13), like intersection points 25 (Fig. 3),
slide in
grooves 244 that retain intersection points 225 and guide the staple in the
10 direction of the skin (not shown). If the intersection points 225 sit
shallowly in
grooves 244, and the staple is elastic enough, the intersection points may
function more like points rather than three dimensional structures. Thus,
without
stabilizing blocks 240 and channels 242, staple 210 might rotate about axis A-
A
(Fig. 13).
The device in Fig. 13 could function with only one thin stabilizing
block 240 and channel 242, or even simply a clip (not shown) attached to inner
backbone face 233 and into which staple crown 220 could fit. An equivalent
structure to a stabilizing block and channel (small or large, one or many)
would
replace block 240 and channel 242 with a slot or hole in applicator backbone
232
into which a pin, hump, or raised portion atop staple crown 220 could be
inserted. In other words, any number of male-female attachments could be used
to interrelate staple crown 220 and backbone 232 of applicator 230.
Figures 14 and 15 show still another embodiment of the present
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invention. Two pairs 341 of tabs 341a and 341b are fastened to inner face 333
of
backbone 332. Each tab holds one end of staple crown 320 and an upper portion
of leg segment 324. Together, the two tabs 341 both guide staple 310 downward
when the applicator arms 334 are squeezed. In addition, the same tabs 341 also
stabilize staple 310, preventing it from rotating about an axis through leg
segment intersection points 325. The same functions can be accomplished by
placing tabs 341 at the top of inner face 335 of applicator arms 334.
Tabs 341 must also retain staple 310 in applicator 330 until the
staple is secured to the skin. In the preferred embodiment discussed above
(e.g.,
Fig. 3), staple 10 is fit with slight frictional resistance into grooves 44.
Figure 15
depicts an alternative that can be used with the embodiment of Fig. 14. Two
small nubs 345a and 345b retain crown 320 of staple 310, so that a small force
must be used to disengage the staple from the tabs by pulling crown 320
through
nubs 345a and 345b. An equivalent structure for accomplishing the same result
would eliminate nubs 345a,b and instead angle tabs 34Ia,b so that tab ends
346a,b are separated by a distance slightly less than the diameter of staple
310.
Thus, one of ordinary skill in the art will understated that a
singular structure may provide more than one function. As described above, for
example, two sets of tabs 341, as depicted in Fig. 14, could provide the
retaining, guiding, and stabilizing functions of the present invention.
Grooves
444 in Fig. 16 do likewise.
In keeping with the numerous structures that can comprise the
present invention, one of ordinary skill will understand that an improvement
of
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the embodiment in Fig. 14 can be created by adding the guidance grooves 44
depicted in Fig. 3. Figure 16 alters that configuration by eliminating the
tabs, so
that grooves 444 accomplish the function of both guiding staple 410 toward its
application while retaining the staple in applicator 430 and preventing
rotation
about intersection points 425 (not shown) where leg segments 424 and 426 meet.
Grooves 444 in Fig. 16 differ from grooves 44 in Fig. 3 in that grooves 444
must be deeper than grooves 44, and points 425 must protrude into grooves 444
deeper than do intersection points 25 into grooves 44. Consequently, in Fig.
16,
grooves 444 of staple 410 retain the staple so it does not fall out of
applicator
430, guide the staple as it changes shape and is secured to the patient, and
stabilizes it against rotation. This differs from the configuration in Fig. 3
in that
leg segments 24,26 of both legs 22 are inserted into groove 44 shallowly
enough
that as a practical matter leg segments 24,26 are secured at intersection
points 25
more as points than as three dimensional structures.
To describe yet another alternative embodiment, the grooves 444
in Fig. 16 are depicted without curves at the bottom of applicator arm 434. As
shown in Fig. 4, the preferred structure terminates grooves 44 with a curved
and/or inwardly facing portion 46. In Fig. 16, grooves 444 terminate before
the
end of applicator arms 434 to ensure that staple 410 does not slide out of
groove
444.
The applicator itself can be configured in still other ways, such as
by using a different finger grip on the outside face of the applicator arms
(e.g.,
finger cups, polygonal ridges, or simply a rough surface that will not slip)
or by
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shaping the applicator backbone in a different manner. As the preceding
discussion demonstrates, there are numerous equivalent structures that can be
utilized in the present invention, which one of ordinary skill will understand
and
appreciate.
Staples of different configuration can be used as long as they
function properly with the applicator. They may, for example, include small
notches at various positions on the staple to facilitate bending during
application,
or they may simply be shaped differently than described above.
As noted above, it is contemplated that the present invention could
be used in a non-catheter situation for small wounds that require only a few
staples, although at some point it becomes more efficient to use a traditional
stapler if the wound is too larger. Conversely, a dual applicator could be
used
for only one staple. The wasted material would be of minimal cost and would
eliminate the need to manufacture and stock two different varieties of the
device.
In the claimed method of medical stapling, it is also contemplated that the
staple
and applicator assembly can be created or fabricated in a number of ways, and
that an emergency might even require one to manually insert a single staple
into
a single applicator. Nor should one be able to defeat the intent of this
invention
by squeezing the applicator with forceps or the like, rather than with one's
own
fingers. One could, however, include short handles attached to the applicator
arms for ease of handling or leverage in squeezing the applicator arms.
Therefore, it will be understood by those of skill in the art that
changes may be made to the present invention in its fabrication and
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configuration, and that the invention may be used differently without
departing
from its spirit. The invention is defined in the following claims.
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