Abstract:
An O-ring is provided for use in an adjustable surgical wound protector having a solid cross-section including a cross-sectional center that is spaced from a central longitudinal axis and a resilient configuration for squeezing into an oblong shape that is insertable into a surgical incision. At least one recess is defined in the O-ring that is selectively sized and shaped to enable a snap-action rolling of the O-ring about the cross-sectional center in predetermined increments. The recess may comprise various cross-sectional shapes, such as, at least one circumferential groove, a plurality of circumferentially positioned recesses, or be shaped such that the O-ring comprises a cruciform cross-section. An improved incrementally adjustable apparatus for protecting an incised wound from exposure to bacterial and other harmful contaminants is also provided including a pair of resilient O-rings connected to opposite ends of an impermeable pliable sleeve. One of the O-rings is formed to engage the inner edge of the wound with a portion of the sleeve above the wound capable of being rolled onto the other ring to draw the remaining sleeve portion contiguous with the sides of the wound.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to surgical wound protectors, and more particularly to an adjustable surgical wound protector for use in protecting incised cavity walls of various thicknesses from harmful contaminants during surgery. 
     BACKGROUND OF THE INVENTION 
     The sides of a wound during surgery are inherently susceptible to bacterial infection if touched by contaminated substances such as diseased body parts and fluids as they pass through the wound. Therefore extreme care must be exercised to insure that the exposed sides of an incision are completely covered by a material impervious to solids and fluids containing bacteria and other contaminants before surgery proceeds. 
     Various techniques have been used to insulate any incised tissue from exposure. One form of protection for relatively large incisions typically employs soft cotton sponges held against the sides of the wound by metal retractors to minimize contamination as well as to give the surgeon better access into the operating site. Another form of wound protector, particularly suitable for surgery, is disclosed in U.S. Pat. No. 3,347,227 to Harrower. Harrower discloses a surgical incision protector consisting of a pair of flexible rings joined by a thin, tubular-shaped sheet of flexible material. Harrower&#39;s rings have sufficient preforming to give a generally oval shape, be resilient and flexible, and so as to be easily flexed for insertion through a wound opening. The thin sheet is preferably made of plastic and must be impermeable to fluids and bacteria, physiologically inert, unaffected by autoclaving or sterilization, free of electrostatic hazard, resistant to melting, non-flammable, and somewhat elastic. Each of Harrower&#39;s flexible rings has a substantially circular cross-section. Harrower&#39;s incision protector is assembled by securing each end of the tubular sheet of flexible material to a ring, so that each ring is positioned at an end of the thin sheet of tubular material. In use, one ring is squeezed into an oblong shape, inserted through the peritoneum, and allowed to expand to the preformed shape over the inside edge of the wound. The other ring overlaps the outside edge causing the sleeve to stretch into contiguous contact with the entire surface of the sides and inner and outer edges of the wound. To obtain a form-fitting contiguous contact with the sides of the wound, the circumference of both rings in their preformed shape are slightly larger than that of the incision, and the extended length of the sleeve between the rings is slightly greater than that of the wall thickness. To accommodate variations in wound size, Harrower&#39;s wound protectors are manufactured in numerous combinations and permutations of both circumference and length. 
     U.S. Pat. No. 3,347,226 to Harrower describes an adjustable wound protector which reduces, to a degree, the number of sizes required. It requires a number of predetermined lengths similar to U.S. Pat. No. 3,347,227, except the circumference of the wound protector is adjustable, before being installed in the wound, by the rings having telescoping ends, and the side of the sleeve having overlapping lengthwise edges. Any overlapping excess may be cut off. The rings have a maximum adjustable circumference slightly larger than that of the largest incision anticipated so that they are sure to overlap the inner and outer edges of the wound. However, a sleeve length must be selected which will closely conform to the wall thickness at the wound. 
     U.S. Pat. No. 5,524,644, issued to Crook discloses an incrementally adjustable apparatus for protecting an incised wound from exposure to bacterial and other harmful contaminants. Crook provides a pair of resilient O-rings that are connected to opposite ends of an impermeable pliable sleeve. One of the O-rings is formed to engage the inner edge of the wound with a portion of the sleeve which is capable of being rolled onto the other ring to draw the remaining sleeve portion contiguous with the sides of the wound. Significantly, Crook relies upon flat surfaces on the rolled ring, that form an oblate cross-section, to provide a gripping surface to turn the ring about its annular axis. 
     SUMMARY OF THE INVENTION 
     In one preferred embodiment, an O-ring is provided for use in an adjustable surgical wound protector comprising a solid cross-section including a cross-sectional center that is spaced from a central longitudinal axis and a resilient configuration for squeezing into an oblong shape that is insertable into a surgical incision. At least one recess is defined in the O-ring that is selectively sized and shaped to enable a snap-action rolling of the O-ring about the cross-sectional center in predetermined increments. The recess may comprise various cross-sectional shapes, such as, at least one circumferential groove, a plurality of circumferentially positioned recesses, or be shaped such that the O-ring comprises a cruciform cross-section. 
     In one preferred embodiment of the invention, an O-ring is provided for use in an adjustable surgical wound protector that comprises a circular torus having a solid cross-section including a cross-sectional center that is radially equidistant from a central longitudinal axis. This O-ring also comprises a resilient configuration that is suitable for squeezing into an oblong shape that is insertable into a surgical incision. Advantageously, two recesses are formed in the O-ring that are selectively sized and shaped to enable a snap-action rolling of the O-ring about the cross-sectional center in predetermined increments. The circular cross-section of the O-rings preferably comprises four quadrants, with the material defining two diagonally opposed quadrants being removed, leaving two diagonally opposed recesses. The solid portion of each O-ring defines a first solid quadrant and a diagonally opposed second solid quadrant, with the first solid quadrant including a curved outer surface, a curved annular surface, and a sinusoidal surface, and the second solid quadrant also including a curved outer surface, a curved annular surface, and a sinusoidal surface. The first and second curved annular surfaces are preferably disposed at substantially the same radial distance from the central longitudinal axis, and are vertically oriented so as to be substantially parallel with the central longitudinal axis. The sinusoidal surfaces extend transversely relative to the central longitudinal axis. 
     An improved adjustable surgical wound protector is also provided that comprises an elongate open-ended tube formed of a pliable material that is impervious to solid and fluid contaminants for inserting lengthwise into a surgical incision. Two O-rings are one each secured around the open ends of the tube. The O-rings have a resilient configuration for overlapping the inner edge of the wound and for squeezing into an oblong shape that is insertable with a lengthwise portion of the sleeve adjacent to one of the O-rings in the surgical incision. Advantageously, at least one of the O-rings comprises at least one recess for enabling selected snap-action rolling of the at least one O-ring for rolling the remaining lengthwise portion of the sleeve on itself about the O-ring to shorten the sleeve in predetermined increments and to resist subsequent lengthening, whereby the sleeve length can be adjusted before or after placement in the wound. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features and advantages of the present invention will be more fully disclosed in, or rendered obvious by, the following detailed description of the preferred embodiment of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts and further wherein: 
     FIG. 1 is a perspective, partially broken away view of an incrementally adjustable surgical wound protector formed in accordance with the present invention; 
     FIG. 2 is a perspective view of an O-ring formed in accordance with a preferred embodiment of the present invention; 
     FIG. 3 is a cross-sectional view of the O-ring shown in FIG. 2, as taken along lines  3 — 3  in FIG. 2, and including a portion of the interior side surface of the O-ring; 
     FIG. 4 is a side elevational view of the O-ring shown in FIG. 2; 
     FIG. 5 is a broken away, cross-sectional view of the incrementally adjustable surgical wound protector shown in FIG. 1, as taken along lines  5 — 5  in FIG. 1, illustrating the interconnection between the O-ring and sleeve; 
     FIGS. 6-9 illustrate in sequence, the operation of the incrementally adjustable surgical wound protector shown in FIG. 1; 
     FIG. 10 is a perspective view of one alternative embodiment of O-ring; 
     FIG. 11 is a side elevational view of the O-ring shown in FIG. 10; 
     FIG. 12 is a cross-sectional view, taken along line  12 — 12  in FIG. 11; 
     FIG. 12A is a cross-sectional view similar to that shown in FIG. 12, but illustrating an alternative cruciform cross-section having radiused end surfaces; 
     FIG. 13 is a perspective view of another embodiment of O-ring; 
     FIG. 14 is a side elevational view of the O-ring shown in FIG. 13; 
     FIG. 15 is a cross-sectional view, as taken along lines  15 — 15  in FIG. 14, showing an alternative cruciform cross-section; 
     FIG. 15A is a cross-sectional view similar to that shown in FIG. 15, but illustrating an alternative cruciform cross-section having radiused end surfaces; 
     FIG. 16 is a perspective view of yet another alternative embodiment of O-ring; 
     FIG. 17 is a side elevational view of the O-ring shown in FIG. 16; 
     FIG. 18 is a cross-sectional view, as taken along line  18 — 18  in FIG. 17, showing an embodiment of recess used in connection with the present invention; 
     FIG. 19 is a perspective view of a further alternative embodiment of O-ring; 
     FIG. 20 is a side elevational view of the O-ring shown in FIG. 19; 
     FIG. 21 is a cross-sectional view, as taken along the line  21 — 21  in FIG. 20; 
     FIG. 22 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 23 is a front elevational view of the O-ring shown in FIG. 22; 
     FIG. 24 is a cross-sectional view, as taken along lines  24 — 24  in FIG. 23; 
     FIG. 25 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 26 is a front elevational view of the O-ring shown in FIG. 25; 
     FIG. 27 is a cross-sectional view, as taken along lines  27 — 27  in FIG. 26; 
     FIG. 28 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 29 is a front elevational view of the O-ring shown in FIG. 28; 
     FIG. 30 is a cross-sectional view, as taken along lines  30 — 30  in FIG. 29; 
     FIG. 31 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 32 is a front elevational view of the O-ring shown in FIG. 31; 
     FIG. 33 is a cross-sectional view, as taken along lines  33 — 33  in FIG. 32 
     FIG. 34 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 35 is a front elevational view of the O-ring shown in FIG. 34; 
     FIG. 36 is a cross-sectional view, as taken along lines  36 — 36  in FIG. 35; 
     FIG. 37 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 38 is a front elevational view of the O-ring shown in FIG. 37; 
     FIG. 39 is a cross-sectional view, as taken along lines  39 — 39  in FIG. 38; 
     FIG. 40 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 41 is a front elevational view of the O-ring shown in FIG. 40; 
     FIG. 42 is a cross-sectional view, as taken along lines  42 — 42  in FIG. 41; 
     FIG. 43 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 44 is a front elevational view of the O-ring shown in FIG. 43; 
     FIG. 45 is a cross-sectional view, as taken along lines  45 — 45  in FIG. 44; 
     FIG. 46 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 47 is a front elevational view of the O-ring shown in FIG. 46; 
     FIG. 48 is a cross-sectional view, as taken along lines  48 — 48  in FIG. 47; 
     FIG. 49 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 50 is a front elevational view of the O-ring shown in FIG. 49; 
     FIG. 51 is a cross-sectional view, as taken along lines  51 — 51  in FIG. 50; 
     FIG. 52 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 53 is a front elevational view of the O-ring shown in FIG. 52; 
     FIG. 54 is a cross-sectional view, as taken along lines  54 — 54  in FIG. 53; 
     FIG. 55 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 56 is a front elevational view of the O-ring shown in FIG. 55; 
     FIG. 57 is a cross-sectional view, as taken along lines  57 — 57  in FIG. 56; 
     FIG. 58 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 59 is a front elevational view of the O-ring shown in FIG. 58; 
     FIG. 60 is a cross-sectional view, as taken along lines  60 — 60  in FIG. 59; 
     FIG. 61 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 62 is a front elevational view of the O-ring shown in FIG. 61; 
     FIG. 63 is a cross-sectional view, as taken along lines  63 — 63  in FIG. 62; 
     FIG. 64 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 65 is a front elevational view of the O-ring shown in FIG. 64; 
     FIG. 66 is a cross-sectional view, as taken along lines  66 — 66  in FIG. 65; 
     FIG. 67 is a perspective view of yet a further alternative embodiment of O-ring; 
     FIG. 68 is a front elevational view of the O-ring shown in FIG. 67; and 
     FIG. 69 is a cross-sectional view, as taken along lines  69 — 69  in FIG.  68 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     This description of preferred embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. In the description, relative terms such as “horizontal,” “vertical,” “up,” “down,” “top” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing figure under discussion. These relative terms are for convenience of description and normally are not intended to require a particular orientation. Terms including “inwardly” versus “outwardly,” “longitudinal” versus “lateral” and the like are to be interpreted relative to one another or relative to an axis of elongation, or an axis or center of rotation, as appropriate. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. The term “operatively connected” is such an attachment, coupling or connection that allows the pertinent structures to operate as intended by virtue of that relationship. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function, including not only structural equivalents but also equivalent structures. 
     Referring to FIG. 1, an incrementally adjustable surgical wound protector  5  comprises a thin flexible sleeve  8  positioned between a first O-ring  10  and a second O-ring  12 . Sleeve  8  comprises a tube having a uniform circumference along its length, an upper end edge  16 , and a lower end edge  18 . Upper end edge  16  of sleeve  8  is fastened or bonded to a surface portion of first O-ring  10  by sealing, e.g., thermally, ultrasonically or, with proper pretreatment, adhesives, but without (i) the portion of sleeve  8  adjacent to upper end edge  16  being wrapped around the circumference of first O-ring  10 , or (ii) overlapped upon itself. Likewise, lower end edge  18  of sleeve  8  is fastened or bonded to a surface portion of O-ring  12  by sealing, e.g., thermally, ultrasonically or, with proper pretreatment, adhesives, but without (i) the portion of sleeve  8  adjacent to lower end edge  18  being wrapped around the circumference of O-ring  12 , or (ii) overlapped upon itself (FIGS.  5 - 9 ). Sleeve  8  may also be attached to O-rings  10 , 12  by adhesive, but with less than satisfactory results. 
     Sleeve  8  is preferably formed from a material that is impervious to solids and/or fluids containing bacteria and other harmful contaminants, e.g., a polymer or elastomeric material of the type known in the art. The materials and dimensions of wound protector  5  are selected to ensure stability of the wound protector when installed. A preferred polymer material suitable for sleeve  8  is a heat-sealable 2-mil aromatic polyether polyurethane film, such as the PT6100 series manufactured by Deerfield Urethane, Inc., under the tradename DUROFLEX, that may be produced in seamless tubular form or by a flat sheet in a cylindrical form with the meeting margins along the side overlapped and sealed. Other materials that may be used with good effect include, polyolefins and other like plastomers and elastomers that are suitable for use in medical applications. A nominal sleeve length suitable for surgery is typically from about 100 to about 200 mm. Sleeve diameters will vary according to the length of the surgical incision. 
     First O-ring  10  and second O-ring  12  each are formed so as to engage the inner edge of a surgical incision, with a portion of sleeve  8  above the incision and capable of being incrementally rolled toward the other O-ring to draw the remaining portion of sleeve  8  contiguous with the sides of the incision. O-rings  10  and  12  are preferably formed from an elastomeric medical grade material of sufficient hardness to retain O-rings  10  and  12  expanded in place around the inner and outer edges of the surgical incision. The material must be compliant enough to allow O-ring  10  or  12  to be turned by the fingers over 180 degrees about its center. For this purpose, urethane is a preferred elastomeric material. O-rings  10 , 12  may be formed from other resilient materials, such as medical grade, polyvinylchloride, silicon, natural rubber, or other elastomeric or rubber-like materials, with good effect. 
     Referring to FIGS. 1-5, O-rings  10 , 12  preferably comprise a circulartorus, i.e., a solid formed by the rotation of a circle about an axis that lies in the plane of the circle, but without cutting the circle. O-rings  10 , 12  are formed from a solid, initially circular cross-section torus having a cross-sectional center  20  that is radially equidistant from a central longitudinal axis  24  of the O-ring. The circular cross-section of each O-ring  10 , 12  may be divided into four quadrants (FIGS. 3, and  5 - 9 ). Material defining two diagonally opposed quadrants is removed, leaving two diagonally opposed recesses  26  and  28  (best shown in FIG.  3 ). 
     The solid portion of O-rings  10 , 12  that remains defines a first solid quadrant  30  and a diagonally opposed, second solid quadrant  33 . First solid quadrant  30  includes a curved outer surface  36 , a curved annular surface  38 , and a sinusoidal surface  40 . Second solid quadrant  33  includes a curved outer surface  46 , a curved annular surface  48 , and a sinusoidal surface  50 . Curved annular surfaces  38 , 48  are at substantially the same radial distance from central longitudinal axis  24 , and are vertically oriented so as to be substantially parallel and substantially coaxial with central longitudinal axis  24 . Sinusoidal surfaces  40 , 50  extend transversely relative to the central longitudinal axis  24  of O-rings  10 , 12  (FIGS.  2  and  3 ). 
     Of course, it will be understood that the term “O-ring” is not limited to circular structures or classic toroidal shapes, but also includes structures that are not circular, e.g., rectilinear, oval/elliptical, hexagonal, octagonal, etc., as long as such rings comprise a resilient configuration capable of being squeezed into an oblong shape that is suitable for insertion into a surgical incision. 
     By way of example, a urethane O-ring  10 , 12  for use with a sleeve having a diameter of about 109 mm, has a diameter of about 7.9 mm, with a radial depth of diagonally opposed recesses  26  and  28  of approximately 4.0 mm. Of course, the sizes of the O-rings and sleeves will vary according to incision size and peritoneum wall thickness. The personal preference of the surgeon will also affect the choice of both O-ring and sleeve size for a particular surgical procedure. Each end of sleeve  8  is sealingly fastened or bonded around an O-ring  10 , 12 , e.g., to a curved outer surface  46 , such that when the sleeve is fully extended, O-rings  10 , 12  are positioned in spaced-apart relation to one another (FIGS.  1  and  5 ). 
     The cross-sectional shape of O-rings  10 , 12  provides stability in a plane perpendicular to central longitudinal axis  24 , and provides an over-center “snap-action” or “snap-roll” when O-ring  10 ,  12  is rolled about itself and sleeve  8 , thereby providing incremental shortening in predetermined increments and resistance to lengthening after shortening. More particularly, by strategically removing portions of O-rings  10 , 12  so as to form recesses  26 , 28 , the rate of twist necessary to create the over-center “snap-action” can be gauged and set. Typically, about 33% to about 70% of the mass of the O-ring must be either removed or redistributed in order to obtain a “snap-action” that is suitable for hand twisting. Thus numerous O-rings (FIGS.  12 - 39 ), having differing amounts, locations, and shapes of material removed from their cross-section maybe used in connection with the present invention. 
     For example, and referring to FIGS. 10-15, rings  10 , 12  may comprise a cruciform cross-sectional profile. In this configuration, the cruciform shape of O-rings  10 , 12  provide stability in a plane perpendicular to central longitudinal axis  24  and also provide the over-center, “snap-action” when rolled about themselves and sleeve  8 . The embodiment disclosed in FIGS. 10-12 include a cruciform cross-section having flat surfaces  60  and  62 . While FIGS. 13-15 show a similar O-ring  10 , 12  having radiused surfaces  65  and  67 . Of course, the end surfaces of the cruciform cross-section O-ring  10 , 12  may also have radiused end surfaces, as shown in FIGS. 12A and 15A. 
     Referring to FIGS. 16-33, O-rings  10 , 12  may also include a plurality of recesses defined into a portion of the ring. More particularly, a plurality of recesses  70  are defined radially inwardly into O-ring  10 , 12 , i.e., toward cross-sectional center  20 , from diametrically opposed positions along the circumference of the O-ring. In this way, recesses  70  extend into O-ring  10 , 12  from each side in an alternating pattern. FIGS. 16-18 illustrate a rectilinearly shaped plurality of alternating recesses  70 , while FIGS. 19-21 illustrate a plurality of round recesses  72  and FIGS. 22-24 illustrate a plurality of round, shallow recesses  72   a  disposed on both sides of O-ring  10 , 12 . 
     Referring to FIGS. 25-33, a sinusoidally defined recess  72   b  may be employed with the present invention. FIGS. 25-27 illustrate such a sinusoidal recess  72   b  disposed on an inner circumferential surface of O-ring  10 , 12 , while FIGS. 28-30 illustrate such a sinusoidal recess  72   b  disposed on an outer circumferential surface of O-ring  10 , 12 . FIGS. 31-33 illustrate a pair of sinusoidal recesses  72   b  positioned in diametrically opposed relation to one another on O-ring  10 , 12 . In each of the foregoing cases, the removal of material from O-ring  10 ,  12  to define recesses  70 ,  72 , or  72   b  provides stability in a plane perpendicular to central longitudinal axis  24 , and provides an over-center “snap-action” when the O-ring is rolled about itself and sleeve  8 . 
     Referring to FIGS. 34-42, O-rings  10 , 12  may also have a continuous recess formed in diametrically opposed portions of O-ring  10 , 12 . More particularly, a top recess  78  and a bottom recess  80  may be formed in O-ring  10 , 12  so as to yield “a bow-tie” cross-sectional profile to O-ring  10 ,  12  (FIGS. 34-36) or may be formed so as to be shallow (FIGS.  37 - 39 ). The removal of material from O-ring  10 ,  12  from diametrically opposed portions in a continuous, or annular fashion, provides stability in a plane perpendicular to central longitudinal axis  24 , and provides an over-center “snap-action” when the O-ring is rolled about itself and sleeve  8 . A plurality of reinforcing ribs  82  may be formed within top recess  78  and/or bottom recess  80  so as to ease manufacture (FIGS.  40 - 42 ). 
     Referring to FIGS. 43-57, O-rings  10 , 12  may also be formed so as to have convex top and bottom walls  86 , 88 , and substantially flat inner and outer, annular side walls  90 ,  92  (FIGS. 43-45) or convex top and bottom walls  86 , 88  and convex inner and outer, annular side walls  94 , 96  (FIGS.  46 - 48 ). The reduction of material from O-ring  10 , 12  coupled with the curvature of either the top and bottom walls  86 , 88  or the annular inner and outer side walls  94 , 96  provides stability in a plane perpendicular to central longitudinal axis  24 , and provides an over-center “snap-action” when the O-ring is rolled about itself and sleeve  8 . 
     Additionally, O-ring  10 , 12  may also be formed so as to have nonparallel top and bottom walls  100 , 102 , and convex inner and outer, annular side walls  104 , 106  (FIGS.  49 - 51 ). Alternatively, O-ring  10 , 12  may also be formed so as to have nonparallel, convex top and bottom walls  108 , 110 , and convex inner and outer, annular side walls  112 , 114  (FIGS.  52 - 54 ). Also, an additional annular flat  116  may be included at the transition between convex inner and outer, annular side walls  112 , 114  and convex top and bottom walls  108 , 110  (FIGS.  55 - 57 ). 
     Referring to FIGS. 58-, O-rings  10 , 12  may also include a plurality of through-holes  120  defined radially through O-ring  10 , 12 , i.e., through cross-sectional center  20 , from diametrically opposed positions along the circumference of the O-ring. FIGS. 58-63 illustrate a plurality of rectilinearly shaped through-holes  120 , and double through-holes  122 , respectively, while FIGS. 64-66 illustrate a plurality of round through-holes  124 . In each case, the removal of material from O-ring  10 ,  12  to define through-holes  120 ,  122 , or  124  provides stability in a plane perpendicular to central longitudinal axis  24 , and provides an over-center “snap-action” when the O-ring is rolled about itself and sleeve  8 . 
     Referring to FIGS. 67-69, in some instances, O-rings  10 , 12  may have additional material added to their circumference so as to form bulbous protrusions  128  over their outer surface, so as to redistribute the mass of the O-ring  10 , 12 . This redistribution of mass and concomitant change in the moment of inertia of O-ring  10 , 12  also provides stability in a plane perpendicular to central longitudinal axis  24 , and provides an over-center “snap-action” when the O-ring is rolled about itself and sleeve  8 . 
     Referring again to FIGS. 6-9, when adjustable surgical wound protector  5  is to be used in an abdominal surgical procedure, the abdomen  55  is routinely prepared with antiseptics; the site for the incision is traced on abdomen  55  and covered with a surgical drape; and a muscle-split is made at the site through the peritoneum. One O-ring (identified by reference numeral  12  in FIGS. 6-9) is squeezed lengthwise and inserted into the surgical incision and through the peritoneum, where it is released and returns to its original circular shape. In this position, O-ring  12  is placed within the body cavity and O-ring  10  is positioned outside of the body cavity, with sleeve  8  extending through the body cavity. It will be understood that O-rings  10 ,  12  are completely interchangeable. Outer O-ring  10  is then gripped by the thumb and fingers and turned outwardly, in opposite directions, so as to roll sleeve  8  incrementally, i.e., so as to create repeated over-center “snap-rolls” of the O-ring. As a consequence, sleeve  8  is reeled onto outer O-ring  10  until outer O-ring  10  abuts the outer surface of abdomen  55 . The portion of sleeve  8  that is in the incision, and between O-rings  10 , 12  is drawn into contiguous contact with the sides of the incision so as to provide a self-retaining protective barrier during surgery which is impervious to contaminating solids and fluids. 
     ADVANTAGES OF THE INVENTION 
     Numerous advantages are obtained by employing the present invention. 
     The present invention provides a relatively low cost surgical wound protector of simplified and selectively adjustable design which can be easily installed in a wound and adjusted in place to form fit a wide range of cavity wall thicknesses for protection against harmful contaminants. 
     Another advantage of the invention is the provision of an adjustable wound protector in which relatively few sizes are needed to form fit a wide range of incision sizes and cavity wall thicknesses. 
     Still another advantage of the invention is the provision of a surgical wound protector which can be adjusted after being inserted in a wound to obtain contiguous contact with the sides of the cavity wall. 
     A still further advantage of the invention is the provision of a single, easily manufactured O-ring design that provides for a “snap=action” when rolled in itself so as to reel a sleeve onto the O-ring after being inserted in an incision for securing the sleeve in contiguous contact with the sides of the incision. 
     It is to be understood that the present invention is by no means limited only to the particular constructions herein disclosed and shown in the drawings, but also comprises any modifications or equivalents within the scope of the claims.