Patent Publication Number: US-2017348173-A1

Title: Surgical support and cover therefor

Description:
The present invention relates to a surgical support for positioning and cushioning part of a patient&#39;s anatomy. 
     Supports are widely used in surgery to position and maintain a particular part of the patient&#39;s anatomy. This may involve supporting a chosen part of the body stably, as where a headrest is used to raise the head and maintain its orientation, or maintaining a certain bodily configuration, as where a support placed beneath the torso of a prone patient is used to provide convex curvature of the spine in order to facilitate spinal surgery. 
     By their nature such supports exert pressure on the body. Prolonged use can lead to complications such as pressure sores. To ameliorate this, surgical supports are provided with cushioning. One known type of surgical support uses a base part of rubber foam to form the support&#39;s gross shape and a layer of memory foam moulded on the base part to provide cushioning. The memory foam is able to deform to accommodate the shape of the supported body part and so helps to distribute pressure more evenly over it. The relatively stiff base maintains the supports overall shape and so ensures a degree of stability. For best effect the memory foam is in contact with the patient&#39;s skin—this helps to avoid pressure sores and accumulation of sweat. Further, if the memory foam is covered, for example, by a textile cover, this can sometimes inhibit lateral spreading of the surface of the memory foam when pressure is applied, thereby rendering it non-conformal, or not as-conformal as may be needed. Typically, therefore, no cover is used and such supports thus need to be discarded and replaced after a single use for the sake of hygiene and safety. 
     A hospital or operating theatre thus needs a considerable inventory of supports. They are bulky items and there are consequent expense, inconvenience and undesirable environmental implications in their manufacture, transportation, storage and disposal. 
     Various aspects of the invention are set forth in the appendant claims. 
     In accordance with a first aspect of the present invention, there is a surgical support comprising a base shaped to support a part of a patient&#39;s anatomy, a removable cover which has an inner surface and an outer surface and is adapted to fit over the base with its inner surface toward the base, and a cushioning pad secured at the outer surface of the cover and positioned to be interposed between the patient and the base in use. 
     According to another aspect of the invention, there is provided a surgical support comprising a base shaped to support a part of a patient&#39;s anatomy, a removable cover which has an inner surface and an outer surface and is adapted to fit over the base with its inner surface toward the base, and a cushioning pad manufactured of memory foam secured to the outer surface of the cover, the cushioning pad being positioned to be interposed between the patient and the cover in use 
     By virtue of the present invention, the pad is in direct contact with the patient, to provide the required cushioning and protection, because it is at the outer surface of the removable cover. The cover and pad can be disposable items but because the relatively bulky base does not need to be replaced after each use the problems of cost, storage and disposal are greatly reduced. 
     In accordance with another aspect of the present invention there is a cover for a surgical support, the cover comprising flexible sheet material for fitting over a base of the surgical support, the sheet material having an inner surface for placement against the base and an outer surface, and a cushioning pad secured at the outer surface of the cover. 
     In accordance with another aspect of the present invention there is a cover for a surgical support, the cover comprising flexible sheet material for fitting over a base of the surgical support, the sheet material having an inner surface for placement against the base and an outer surface, and a memory foam cushioning pad secured at the outer surface of the cover. 
     In certain embodiments the cushioning pad comprises memory foam. 
     The cover may comprise flexible sheet material. It may be provided with a retainer arrangement for retaining the cover in place upon the base in use. The retainer arrangement may comprise elastic or a drawstring extending around at least part of the cover&#39;s periphery. The cover may comprise a textile material. 
     Moulded rubber foam is a suitable material for the base, although other materials could be selected. In certain embodiments the base provides a support surface for supporting the part of the patient&#39;s anatomy and the pad of foam is shaped to complement the support surface. 
     The surgical support is typically to be placed upon an operating table in use and to that end, in certain embodiments, comprises an underside adapted to rest stably on a table. The underside of the base may be substantially flat. 
    
    
     
       Specific embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:— 
         FIGS. 1 to 3  are each sectional views, taken in a longitudinal plane, of a surgical support of known type; 
         FIGS. 3 to 6  are each sectional views, taken in a longitudinal plane, of a surgical support embodying the present invention; 
         FIG. 7  represents a base of the surgical support of  FIGS. 3 to 6  viewed from above and to one side, a cover being omitted; 
         FIG. 8  is similar to  FIG. 7  but shows the surgical support with the cover in place; and 
         FIG. 9  shows an alternative embodiment of the invention in kit form. 
     
    
    
     The surgical support  10  represented in  FIGS. 1 to 3  belongs to the prior art. It comprises an ergonomically shaped base  12  which forms the gross shape of the support. In this example the base  12  is moulded from rubber foam rigid enough to substantially maintain its shape in use. The base  12  has an upper face which supports a part of the patient&#39;s body in use and this face is covered by a layer of memory foam  14 , which serves to cushion the patient&#39;s body and help to distribute pressure over it. The surgical support  10  may for example be placed upon the operating table during an operation to maintain the patient in a desired position. The example illustrated is a head support. It can be placed upon an operating table to maintain the head&#39;s position. In some cases it may be desirable to alter the inclination of the surgical support  10  and  FIGS. 2 and 3  show an optional wedge  16  for this purpose, placed beneath the base  12 . 
     The memory foam  14  is permanently secured to the base  12 . For the reasons explained above, the known surgical support  10  is a single use item. 
     The surgical support  20  represented in  FIGS. 3 to 8  embodies the present invention. It comprises an ergonomically shaped base  22  which once more defines the gross shape of the support and is sufficiently rigid to substantially maintain its shape under the weight of the supported body part. The base  22  may be moulded from rubber foam or other suitable material. Its underside  23  is adapted to rest upon a supporting table such as an operating table, being flat in the illustrated embodiment. 
     Carried upon the base  22  is a cover  24  comprising flexible sheet material. The particular sheet material used may be chosen according to specific requirements but textiles are suitable. The cover  24  may be impermeable to fluids, to resist contamination of the base  22  with bodily fluids and other matter, but in the illustrated embodiment it is made of porous textile. An arrangement is provided for retaining the cover  24  on the base  22 . In the illustrated embodiment this takes the form of an elasticated hem or drawstring which extends around the cover&#39;s periphery and is schematically represented at  26  in  FIGS. 4 to 6 . The cover  24  overlies the entirety of support surface  28  of the base  22  and thus prevents direct contact of the patient with the base  22  in use. It also extends beneath the support so that by drawing the cover&#39;s periphery together the drawstring or elasticated hem  26  keeps the cover in place in use, although it can easily be removed thereafter. 
     The cover  24  has an inner surface  30  which, in use, faces toward and contacts the base  22 . It also has an outer surface  32  upon which is carried a pad  34  of memory foam. 
     The memory foam, in a preferred embodiment of the invention, comprises combustion Modified Polyurethane visco-elastic foam (grade VE50/055), having a density of 48-52 kgm −&#39; and a hardness of 46-64 N. 
     The pad  34  may take various forms according to the specific purpose of the surgical support  20 . In the illustrated example it comprises a pad which is initially flat but which conforms to the shape of the support surface  28  under the weight of the supported body part. The pad  34  could instead be pre-formed to match the contours of the base  22 . The pad  34  covers only part of the support surface  28  in this embodiment but in others it may cover the entirety of the support surface. The plan shape of the pad  34  complements the shape of the base  22  and its position is such that the pad  34  is interposed between the supported part of the patient&#39;s anatomy and the base in use, to provide the desired cushioning effect. 
     Memory foam has particularly advantageous properties. It is able to deform under pressure, shaping itself to a supported body part and so distributing pressure over it, and following removal of the pressure it recovers its original shape over a period of time—a property sometimes referred to as “viscoelasticity”. Known polyurethane memory foam, especially low resilience polyurethane foam (LRPu) may be used in the present invention. Some memory foams are able to deform permanently or semi-permanently subject to body pressure and heat and these too may be used in embodiments of the invention. 
     An advantage of interposing the memory foam pad  34  between the patient and the cover  24  is that the patient is (or can be) placed in direct contact with the memory foam. Thus, the memory foam pad  34  can act as an absorbent layer, to help keep the patient&#39;s skin and/or hair dry (or drier) over prolonged periods of use. This configuration is generally contraindicated by conventional wisdom in the art whereby possible adhesion of the body to the pad is to be avoided (for example, by clotted blood). 
     However, surprisingly, the advantages of having the patient in direct contact with the memory foam pad greatly outweigh the possible disadvantage of adhesion. Specifically, by placing the patient&#39;s skin/body/hair in direct contact with the memory foam pad, the memory foam pad&#39;s surface is able to deform in various directions, such as in the direction of the thickness of the pad, as well as laterally i.e. spread or compress in the plane of the pad. This has been found to give rise to improved conformity of the pad with the patient&#39;s anatomy, as well as reducing and/or avoiding wrinkling of the pad and/or patient&#39;s skin, which may otherwise lead to pinching, skin creases, pressure sores and the like. Further, the possibility of a wrinkled cover coming into contact with the patient&#39;s skin is also avoided by the placement of the memory foam pad between the patient and the cover, as required by embodiments of the invention. 
     Thus, the invention is contraindicated according to overwhelmingly accepted theatre practices. However, the perceived disadvantages and contraindications of placing the memory foam pad in contact with the patient&#39;s skin have been found, in many cases, to be over-stated, whereas the advantages of the invention (placing the memory foam in contact with the patient&#39;s skin) have been found to more than outweigh any possible disadvantages. 
     A further embodiment of the invention, in kit form, is shown in  FIG. 9  of the drawings in which the cover  24  and memory foam pad  34  are supplied as separate items. This configuration facilitates attaching the cover  24  to the base  22  because it is not necessary, whilst attaching the cover  24 , to correctly align the pad  34  with the base. Thus, in use, the base  24  can be covered  45  with the cover  24 , and positioned on the operating table as required. The memory foam pad  34  can then be affixed to the exterior surface of the cover  24 , for example suing self-adhesive strips  40 . In the illustrated embodiment, the self-adhesive strips  40  are provided in substantially parallel rows on the back face  42  of the memory foam pad  34 , although any configuration or orientation of self-adhesive strip or strips  4  could be used. The or each self-adhesive strip  40  comprises a pressure-sensitive adhesive layer that adheres to the exterior surface of the cover  24 . Prior to use, the or each self-adhesive strip  40  is protected by a peel-off layer  44  to prevent the pad  34  from inadvertently sticking to objects prior to use. The peel-off layers  44  are removed immediately prior to use, then the pad  34  is placed  46  over the cover  24  in a desired position and pressed down to secure the pad  34  to the cover  24 . Some subsequent adjustment may be achieved by moving the cover  24  relative to the base  22 , but this may not always be necessary. 
     Various advantages arise from providing the invention in kit form, such as reduced manufacturing cost (cost savings can be passed onto hospitals); the ability to mix-and-match different covers  24  with different pads  34 ; reduced set-up time as the pad  34  can be placed after the base  22  and cover  24  have been positioned; and improved conformity because the pad can be used to overlie/mask any creases in the cover  24 , rather than possibly puckering the pad, as might otherwise be the case. 
     The kit-form embodiment of the invention is suitably supplied to end users in a sealed and/or hermetically-sealed bag containing one or more covers and one or more pads. 
     The present invention is applicable to supports for many parts of the anatomy—head supports, torso supports, foot supports, leg supports and so on—and accordingly the shape of the base  22  and of the pad  34  may differ altogether from the embodiment represented herein. The base  22  of  FIG. 4  is formed by a single moulding, but in other embodiments it may be comprise two or more parts.  FIGS. 5 and 6  show an example, having a wedge  36  placed beneath the main part of the base  22  to change its inclination. The cover  24 —which is a loose fit—is able to accommodate and cover both the main base part  22  and the wedge  36 . It can assist in maintaining the relative positions of the base  22  and the wedge  36 , resisting the natural tendency of the base  22  to slip down the inclined upper surface of the wedge. The base may have other removable parts. For example a chest support for a prone patient may have removable portions to accommodate the bust of a female patient, enabling it to be used with patients of either gender. Also the support may be shaped and proportioned for use with children. While its principal intended use relates to human patients, there is no reason why it should not be adopted for treatment of animals and the word “patient” may be correspondingly construed. 
     The cover  24  (including its pad  34 ) can be disposable items intended for a single use only. The base  22 , however, can by virtue of the present invention be used multiple times. Thus only a relatively small inventory of the bulky base  22  need be maintained. This reduces purchase costs and storage requirements, since the covers  24  can be relatively cheap and compact. Also where the cushioning of memory foam is not required the base  22  can be used without padding, to further reduce inventory and cost. 
     The following statements are not the claims, but relate to various possible features and/or embodiments of the invention:
     Statement 1. A cover for a surgical support, the cover comprising flexible sheet material for fitting over a base of the surgical support, the sheet material having an inner surface for placement against the base and an outer surface, and a memory foam cushioning pad secured, in use, to the outer surface of the cover such that, in use, the cover is interposed between the base and the cushioning pad.   Statement 2. The cover of statement 1, further comprising self-adhesive means interposed between the memory foam cushioning pad and the outer surface of the cover.   Statement 3. The cover of statement 2, wherein the self-adhesive means comprises one or more strips of pressure-sensitive self-adhesive.   Statement 4. The cover of statement 2 or statement 3, wherein the self-adhesive means comprises a double-sided pressure-sensitive self-adhesive strip affixed on a first side to the memory foam cushioning pad and on a second side to a peel-away protective layer, the peel-away protective layer being removable prior to use to expose the second side for affixing memory foam cushioning pad to the cover.   Statement 5. The cover of statement 2 or statement 3, wherein the self-adhesive means comprises a double-sided pressure-sensitive self-adhesive strip affixed on a first side to the cover and on a second side to a peel-away protective layer, the peel-away protective layer being removable prior to use to expose the second side for affixing cover to the memory foam cushioning pad.   Statement 6. The cover of any preceding statement, further comprising a retainer arrangement for retaining the cover in place upon the base in use.   Statement 7. The cover of statement 6 in which the retainer arrangement comprises elastic or a drawstring extending around at least part of the cover&#39;s periphery.   Statement 8. The cover of any preceding statement, in which the flexible sheet material comprises a textile.   Statement 9. A surgical support comprising a base shaped to support a part of a patient&#39;s anatomy, and a removable cover according to any preceding statement, the removable cover comprising an inner surface and an outer surface and is adapted to fit over the base with its inner surface toward the base, and wherein the memory foam cushioning pad is secured, in use, to the outer surface of the cover, the cushioning pad being positioned to be interposed, in use, between a patient and the cover.   Statement 10. A cover or surgical support according to any preceding statement, wherein the memory foam comprises combustion modified polyurethane visco-elastic foam.   Statement 11. A cover or surgical support according to any preceding statement, wherein the memory foam has a density of substantially 48-52 kgm −3 .   Statement 12. A cover or surgical support according to any preceding statement, wherein the memory foam has a hardness of substantially 46-64 N.   Statement 13. The surgical support of any of statements 9 to 12, in which the base comprises moulded rubber foam.   Statement 14. The surgical support of any of statements 9 to 13, in which the base provides a support surface for supporting the part of the patient&#39;s anatomy and the pad of foam is shaped to complement the support surface.   Statement 15. The surgical support of any of statements 9 to 14, which has an underside adapted to rest stably on a table.   Statement 16. The surgical support of statement 15, in which the underside of the base is substantially flat.   Statement 17. A kit comprising cover, and memory foam cushioning pad according to any of statements 1 to 8.   Statement 18. The kit of statement 17, further comprising a base according to any of statements 9 and 13 to 16.   Statement 19. The kit of statement 17 or statement 18, further comprising a sealed outer bag for sealingly enclosing the cover and memory foam cushioning pad prior to use.   Statement 20. A surgical support substantially as herein described with reference to, and as illustrated in, accompanying  FIGS. 4 to 9 .   Statement 21. A cover for a surgical support substantially as herein described with reference to, and as illustrated in, accompanying  FIGS. 4 to 9 .