U.S. patent number 3,668,050 [Application Number 05/017,431] was granted by the patent office on 1972-06-06 for surgical drape.
This patent grant is currently assigned to Kimberly-Clark Corporation. Invention is credited to Harold F. Donnelly.
United States Patent |
3,668,050 |
Donnelly |
June 6, 1972 |
SURGICAL DRAPE
Abstract
Disposable surgical drape comprising a fibrous base sheet having
a primary operative area; a sheet of fluid impervious plastic film,
such as polypropylene film, laminated to the base sheet in the
primary operative area; and a sheet of fluid absorbent plastic foam
material, such as a thin sheet of polyurethane foam, laminated to
the outer surface of the film.
Inventors: |
Donnelly; Harold F. (Appleton,
WI) |
Assignee: |
Kimberly-Clark Corporation
(Neenah, WI)
|
Family
ID: |
21782552 |
Appl.
No.: |
05/017,431 |
Filed: |
March 9, 1970 |
Current U.S.
Class: |
128/849; 128/853;
128/852 |
Current CPC
Class: |
A61B
46/00 (20160201) |
Current International
Class: |
A61B
19/00 (20060101); A61B 19/08 (20060101); A61f
013/00 (); B32b 003/26 (); B32b 027/40 () |
Field of
Search: |
;161/190,159,160,165,249,39,156,112,169,164,145,247,251,72,270
;128/132,132D |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Burnett; Robert F.
Assistant Examiner: Cosby; C. B.
Claims
1. An improved disposable surgical drape comprising the combination
of a flexible fibrous nonwoven base sheet having a primary
operative area, a flexible fluid impervious plastic film bonded to
one surface of said base sheet and covering said primary operative
area, and a sheet of fluid absorbent flexible open-cell plastic
foam material united to the outer surface of said film, said foam
material having a surface frictional coefficient of at least about
20.degree., said film and said foam both being stable at
temperatures up to at least about 160.degree. F. to permit
sterilization of the surgical drape, the combination in said
primary operative area of said base sheet of plastic film bonded
thereto and plastic foam united to said film providing a fluid
absorbent surface with frictional resistance to sliding movement of
instruments and the like resting thereon when the drape is
positioned on a patient, and a fluid barrier to prevent fluids
absorbed by said foam material from striking
2. An improved surgical drape as set forth in claim 1 wherein said
plastic film is selected from the group consisting of polyethylene
film, polypropylene film, polyvinyl chloride film, and
polyethylene
3. An improved surgical drape as set forth in claim 1 wherein said
plastic foam material is selected from the group consisting of
polyester
4. An improved surgical drape as set forth in claim 1 wherein said
sheet of
5. An improved surgical drape as set forth in claim 1 wherein said
plastic
6. An improved surgical drape as set forth in claim 1 wherein said
plastic film is adhesively bonded to said plastic foam material and
to said
7. An improved surgical drape as set forth in claim 1 wherein said
plastic foam material is colored to minimize glare in said primary
operative area.
8. An improved surgical drape as set forth in claim 1 wherein said
drape sheet is a laparotomy sheet having an operative opening in
the fenestration area thereof, and said film is laminated to said
base sheet
9. An improved surgical drape as set forth in claim 1 wherein said
drape sheet has a Stoll abrasion of at least about 200 cycles dry
and at least
10. An improved surgical drape as set forth in claim 1 wherein said
sheet of foam material has an absorbency of at least about 150
percent and at
11. In a disposible surgical drape, the combination comprising a
strong flexible fibrous nonwoven base sheet having a primary
operative area and an area outside said primary operative area, and
a flexible film-foam laminate bonded to the top surface of the base
sheet and covering said primary operative area with a film adjacent
said base sheet and the surface of the foam exposed, said film-foam
laminate including a layer of flexible fluid impervious plastic
film united to a sheet of flexible fluid absorbent open-cell
plastic foam material having a surface frictional coefficient of at
least about 20.degree., said plastic film and said plastic foam
material both being stable at temperatures up to about 160.degree.
F. to permit sterilization of the surgical drape, the combination
of said nonwoven base sheet and laminate bonded thereto providing a
fluid absorbent surface in said primary operative area with
frictional resistance to sliding movement of instruments and the
like resting thereon when the drape is positioned on a patient, and
a fluid barrier to prevent fluids absorbed by said foam material
from striking
12. In a disposable surgical drape, the combination as set forth in
claim 11 wherein said film-foam laminate is over only said primary
operative area of said base sheet, and the area outside said
primary operative area
13. In a disposable surgical drape, the combination as set forth in
claim 12 wherein said film-foam laminate is over only said primary
operative area of said base sheet providing a fluid absorbent and
frictional surface, and said base sheet is water rellant such that
on the surface of said base sheet outside said primary operative
area water runs off rather
14. A disposable surgical drape having a primary operative area
with a fenestration and a drape area outside said primary operative
area, said drape area comprising a strong flexible fibrous nonwoven
material, and said primary operative area comprising a flexible
film-foam laminate, said laminate being bonded to the top surface
of the nonwoven material with the film adjacent said material and
the surface of the foam exposed, said film-foam laminate including
a layer of flexible fluid impervious plastic film united to a layer
of flexible fluid absorbent open-cell plastic foam material and
having an abrasion resistant surface with a frictional coefficient
of greater than about 20.degree., said plastic film said plastic
foam material and said nonwoven material all being stable at
temperatures up to about 160.degree. F. to permit sterilization of
the surgical drape, and both layers of said laminate extending
around said fenestration and to the edge of said fenestration to
provide a fluid absorbent surface with frictional resistance to
sliding movement of instruments and the like resting thereon when
the drape is positioned on a patient, and a fluid barrier to
prevent fluids absorbed by said foam
15. A disposable surgical drape having a primary operative area
with a fenestration and a drape area outside said primary operative
area, said drape area comprising a strong flexible fibrous nonwoven
material, and said primary operative area comprising a flexible
film-foam laminate, said laminate being bonded to the top surface
of the nonwoven material with the film adjacent said material and
extending to the edge of the fenestration and the surface of the
foam exposed, said film-foam laminate including a layer of flexible
fluid impervious plastic film united to a layer of flexible fluid
absorbent open-cell plastic foam material and having an abrasion
resistant surface with a frictional coefficient of greater than
about 20.degree., said plastic film said plastic foam material and
said nonwoven material all being stable at temperatures up to about
160.degree. F. to permit sterilization of the surgical drape, the
united film and foam layers providing a laminate which is strong,
has an abrasion resistant surface even when exposed to the liquids
and physical contact and manipulation encountered in the primary
operative area during an operation, has a fluid absorbent surface
with frictional resistance to sliding movement of instruments and
the like resting thereon when the drape is positioned on a patient,
and provides a fluid barrier extending to the edge of the
fenestration to prevent fluids absorbed by said foam material from
striking through the drape around the fenestration.
Description
DESCRIPTION OF THE INVENTION
The present invention relates generally to surgical drapes and,
more particularly, to an improved construction for the operative
areas of surgical drapes, such as the fenestration area of
laparotomy sheets for example.
It is a primary object of the present invention to provide an
improved surgical drape having an operative area which is strong
and fluid impervious with an outside surface which is absorbent and
which has a high frictional coefficient to provide good non-slip
characteristics.
It is another object of the invention to provide an improved
surgical drape which has a high abrasion resistance.
It is still another object of the invention to provide an improved
disposable surgical drape of the foregoing type which is stable
under the conditions encountered in sterilization treatments,
either by steam or by ethylene oxide and the like.
A further object of the invention is to provide an improved
disposable surgical drape of the type described above which
prevents the passage of bacteria through the operative area of the
drape.
A still further object of the invention is to provide such an
improved surgical drape which has all of the aforementioned
characteristics and yet can be produced at a cost sufficiently low
to permit disposal of the drape after a single use.
Other objects and advantages of the invention will be apparent from
the following detailed description taken in connection with the
accompanying drawings in which:
FIG. 1 is a plan view of a laparotomy sheet embodying the
invention;
FIG. 2 is a section taken along line 2--2 in FIG. 1; and
FIG. 3 is a schematic side elevation of a preferred system for
producing the material used in the laparotomy sheet of FIGS. 1 and
2.
While the invention is susceptible of various modifications and
alternative forms, certain specific embodiments thereof have been
shown by way of example in the drawings which will be described in
detail herein. It should be understood, however, that it is not
intended to limit the invention to the particular forms disclosed,
but, on the contrary, the intention is to cover all modifications,
equivalents, and alternatives falling within the spirit and scope
of the invention.
A wide variety of surgical drapes are in common use today as a
means of preventing contamination during surgical operations. The
trend today is toward the use of disposable drapes, and there has
been a continuing effort to develop improved materials which will
provide the desired combination of properties required for surgical
drapes, and yet can be produced at a cost which is low enough to
permit disposal of the drapes made therefrom after a single use.
For certain types of drapes, such a variety of different properties
are required that it has been difficult to develop a material which
satisfies all the requirements and which can be produced
economically enough to be considered disposable. For example, the
material in the fenestration area of a laparotomy sheet, i.e., the
area in which the operation is performed, must satisfy the
following requirements;
1. The material must be strong and abrasion resistant even when
exposed to the liquids and physical contact and manipulation
encountered during the operation.
2. The material must be fluid impervious, both to prevent the
liquids encountered during operating procedures from striking
through the sheet, and to prevent the passage of bacteria through
the sheet.
3. The material must have a high frictional coefficient to prevent
the dislodgment of surgical instruments, supplies, and the like
from the surface of the sheet during the operation.
4. The material must be stable at the conditions encountered in
sterilization treatments either by stream or by ethylene oxide or
the like.
5. The material must be fluid absorbent to minimize fluid run-off
during the operation.
6. The material must have good draping characteristics.
All the above requirements must be satisfied in a material which
can be produced at a cost low enough to render the material
disposable.
In accordance with the present invention an improved disposable
surgical drape which satisfies all the foregoing criteria comprises
the combination of a fibrous sheet having a primary operative area,
a fluid impervious flexible plastic layer laminated to the base
sheet in the primary operative area, and a sheet of fluid absorbent
flexible plastic foam material on the outer surface of the film.
Thus, the illustrative laparotomy sheet shown in FIG. 1 includes a
base sheet 10 comprising outer layers of cellulose wadding and
inner layers of highly drafted fibers disposed angularly to each
other. A spaced-pattern of adhesive is disposed between each fiber
layer and its adjacent wadding layer with the fibers in each fiber
layer partially embedded in and held by the adhesive of its
adjacent adhesive layer and partially embedded in and held by the
adhesive in the other adhesive layer where it extends between the
fibers of its adjacent fiber layer and with a portion of the
adhesive in both adhesive layers joined where the adhesive patterns
are superimposed. This material is described in more detail in
Sokolowski et al. U.S. Pat. No. 3,484,330, and assigned to the
assignee of the present invention.
In keeping with the present invention, a sheet of fluid impervious
plastic film 11 is laminated to the top surface of the base sheet
10 over the primary operative area of the sheet, which in the
exemplary embodiment is the fenestration area of a laparotomy
sheet. A laparotomy sheet is an elongated, generally rectangular
sheet used to cover all but the operative field of a patient during
thoracic or abdominal surgery, and is typically about 6 to 8 feet
in length and about 3 to 6 feet in width. The film 11 may be bonded
to the fibrous base sheet 10 by any suitable means, such as by
means of an adhesive or by extruding the film directly on the base
sheet 10. The film 11 provides a fluid impervious barrier on the
top surface of the operative area of the sheet 10, so that any
fluids which contact this area cannot strike through the sheet. It
also prevents the transfer of bacteria through the sheet to insure
sterile conditions in the operative area. The film must be capable
of remaining stable under the conditions encountered in the
particular treatment to which the laparotomy sheet is subjected to
render it sterile, e.g., temperatures of about 270.degree. F. for
steam sterilization, or about 160.degree. F. for sterilization by
means of ethylene oxide or the like.
Examples of suitable films are polyethylene, e.g., 2-mil antistatic
polyethylene film manufactured by Clopay Film Corp.; antistatic
polypropylene, e.g., "Extrel II" available from Extrudo Film Corp.;
polyethylene methylacrylate co-polymer film manufactured by Edison
Plastics Company; and vinyl chloride films. The film should be
substantially free of pinholes, and thus must generally be at least
0.15 mil thick, to provide the desired sterility barrier.
To provide a fluid absorbent outer surface on the drape, while at
the same time providing a high frictional co-efficient, a sheet of
fluid absorbent flexible plastic foam material 12 is laminated to
the outer surface of the fluid impervious film 11. The foam
material 12 may be bonded to the film 11 by any suitable means,
such as by means of an adhesive, by fusing, or by extruding the
film 11 directly on the foam material 12.
The absorbency of the absorbent open-cell foam 12 prevents
excessive fluid runoff, and yet the absorbed fluids cannot strike
through the drape because of the intermediate layer of fluid
impervious film 11. The relatively high frictional coefficient of
the foam material provides a substantially non-slip surface which
prevents the accidental dislodgment of surgical instruments and the
like. In addition, the foam 12 should have a low glare, which may
be achieved by using a colored foam. Examples of suitable foams are
40 mil polyester polyurethane foam, available from Reeves Bros. or
Tenneco Chemicals, Inc., having a density of 1.75 lbs./ft..sup.3,
and polyether polyurethane foams. The foam thickness should
generally be in the range of from about 25 mils to about 100 mils,
and the absorbency of the foam sheet should be at least about 150
percent and at least about 3 gm. per 4 .times. 4 inches sample,
preferably at least 575 percent and at least 4.5 gm. per 4 .times.
4 inches sample. The foam sheet should also have a frictional
coefficient of at least about 20.degree..
In order to prevent sparking due to the build-up of static
electrical charges on the drape, which can be hazardous with the
potentially explosive gases that are often present in the operating
room, the foam 12 should also be antistatic. It is not necessary
for the intermediate film 11 to be antistatic unless the specific
design of the drape is such that the film 11 is exposed in a
certain area, e.g., around the operative opening in the
fenestration area of a laparotomy sheet.
the final drape sheet should have a Stoll abrasion of at least
about 200 cycles, and preferably at least 500 cycles, both dry and
wet. The outer layer of foam provides sufficient absorbency to
prevent excessive fluid run-off, and yet the intermediate layer of
fluid impervious film prevents the liquid from striking through the
sheet, as well as providing a bacteria barrier. Moreover, the
relatively high frictional coefficient of the foam provides good
non-slip characteristics to prevent dislodgment of surgical
instruments, supplies and the like from the surface of the sheet
during the operation. Furthermore, the sheet has good draping
characteristics, can be easily sterilized, and can be produced at a
cost low enough to render the drape disposable.
One preferred method of producing the illustrative drape material
is illustrated in FIG. 3. In this process, the plastic film is
unwound from a roll 20 and passed through the nip formed by an
adhesive print roll 21 and a rubber pressure roll 22 so as to apply
a predetermined pattern of adhesive to one side of the plastic
film. The adhesive-coated film is then passed around the rubber
pressure roll 22 and laminated to the underside of a web of
flexible plastic foam 23 unwound from a roll 24. In order to insure
intimate engagement and bonding between the adhesive-coated side of
the plastic film and the plastic foam 23, the two webs are passed
through a nip formed by a rubber roll 25 and a rubber squeeze roll
26 which press the two webs together, after which the composite
laminated material is wound up on a roll 27.
Suitable adhesives for use in the process illustrated in FIG. 3 are
aqueous emulsion adhesives, such as "Polycryl 7F8," manufactured by
Polymer Industries, Inc.; "Jedbond 83-117," manufactured by Jedco
Chemical Company; and "EA-8981", manufactured by the Chemical
Division of Borden Inc. The adhesive is suitably applied to the
film at a loading of 2 to 10 grams per square yard and may be
applied at room temperature. The pressure used to laminate the
adhesive-coated film to the foam material is relatively light, and
is just sufficient to make good contact between the film and
foam.
After the film-foam laminate is formed, it is laminated to the base
sheet 10 by any suitable technique, either manual or automatic, and
either as a separate operation for each separate article or as a
continuous operation similar to that illustrated for the film and
foam materials in FIG. 3. When the film 11 is attached to the base
sheet 10 by adhesive bonding, the same adhesives mentioned above,
for use in forming the film-foam laminate, may be used.
In one example of the invention, a web of antistatic polyethylene
film, 2 mils in thickness, was coated with an aqueous emulsion
adhesive (Polycryl 7F8, made by Polymer Industries, Inc.) at a
loading of 5 grams per square yard at room temperature, using a
printing roll having a surface roughened by sandblasting. The
adhesive-coated side of the film was then laminated to a web of
polyester polyurethane foam, 40 mils in thickness, and the two webs
were pressed together at a pressure of one pound per lineal inch.
Next the film-foam laminate was laminated to a tissue-fiber base
sheet of the type described in the aforementioned Sokolowski et al.
U.S. Pat. No. 3,484,330, which has been treated to render it water
repellant the lamination was accomplished by first coating the film
side of the foam-film laminate with the same adhesive mentioned
above, and then manually pressing the two materials together. The
entire process was carried out at room temperature.
The resulting material was tested for abrasion resistance,
absorbency, and frictional coefficient, with the following
results:
Stoll Abrasion Absorbency Frictional Coefficient
__________________________________________________________________________
Dry Wet % Gm./4".times.4" Angle (degrees) 1,100 5,000 + 583 4.48
30.degree.
__________________________________________________________________________
The properties referred to above were determined as follows:
Abrasion Resistance:
Run on a Stoll abrasion tester with an Appleton Wire Works
54.times.34 mesh chrome screen, loaded with 1 lb. for 0-1,000
cycles, 2 lbs. for 1,001-1,500 cycles, 4 lbs. for 1,501-2,000
cycles and 8 lbs. for 2,001-2,500 cycles.
Absorbency: Sample 4.times. 4 inches immersed in 30.degree. C.
water and then drained for 30 seconds. Weighed before immersion and
after draining to determine gms. water absorbed, and percent weight
gain.
Frictional Coefficient:
Stainless Steel surgical instrument placed on surface to be tested,
which in turn is attached to an adjustable inclined plane. Angle of
plane is adjusted until instrument begins to slip, which angle is
the recorded frictional coefficient.
* * * * *