Abstract:
A support surface suitable for use with a stretcher includes multiple foam pads of independent zonal pressure support such that a transfer of force by pressure on one foam pad to an adjacent foam pad is limited.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    (NOT APPLICABLE) 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    (NOT APPLICABLE) 
       BACKGROUND OF THE INVENTION 
       [0003]    The invention relates to a support surface suitable for use with a stretcher and, more particularly, to a support surface that provides patient pressure redistribution by incorporating multiple pads of independent zonal pressure support. 
         [0004]    Conventionally, stretchers are used without pads or may include a single padded layer for increased patient comfort. Such a padded layer, however, provides only minimal support particularly in the patient&#39;s higher pressure areas such as the head or heels. 
         [0005]    Additionally, due to the construction of the pad layer, pressure in one area of the pad necessarily causes tension in another area of the pad, for example, when a more pointed body part such as the patient&#39;s head or heels is supported by the pad, the pad beneath the patient&#39;s head or heels is deflected, thereby also deflecting adjacent areas. This pressure distribution renders the stretcher less comfortable and may actually unintentionally aggravate a wound or injury. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    It would thus be desirable for a stretcher support surface or pad that is constructed to accommodate body areas that require less or more support. Additionally, it would be desirable to provide such a support surface that provides excellent patient pressure redistribution while preventing pressure on one area of the pad to be transferred to an adjacent area of the pad. 
         [0007]    In an exemplary embodiment, a support surface suitable for use with a stretcher includes a base layer and a plurality of foam support zones supported by the base layer. The foam support zones include a head section, a body section, and a foot section separated by a plurality of lateral channels. Densities of the foam support zones vary by section. The lateral channels may extend through the plurality of support zones to the base layer. In one arrangement, the body section includes an upper body section, a middle body section, and a lower body section, where densities of the foam support zones in the upper, middle and lower body sections vary by section. In another arrangement, the foam support zones further include a longitudinal channel dividing the head, body and foot sections into left side and right side head, body and foot sections. Preferably, the longitudinal channel extends through the plurality of support zones to the base layer. 
         [0008]    The density of the head section is preferably lower than the density of the body section, and the density of the foot section is preferably lower than the density of the body section. Moreover, the density of the foot section is preferably lower than the density of the head section. 
         [0009]    The foot section slopes downward, preferably in an arc, from the body section. 
         [0010]    The support surface may additionally include a top layer disposed over the plurality of foam support zones. In this context, the top layer is formed of a visco-elastic foam material. 
         [0011]    In one arrangement, the head section includes a foam block having a lateral slot therein parallel to the lateral channels separating the head section, the body section, and the foot section. The body section may comprise a plurality of foam blocks separated by body lateral channels parallel to the lateral channels separating the head section, the body section, and the foot section. The foot section may comprise a foam block having at least one lateral slot therein parallel to the lateral channels separating the head section, the body section, and the foot section. 
         [0012]    In another exemplary embodiment, a support surface suitable for use with a stretcher includes multiple foam pads of independent zonal pressure support such that a transfer of force by pressure on one foam pad to an adjacent foam pad is limited. 
         [0013]    In yet another exemplary embodiment, a stretcher pad includes a foam base layer, a middle layer, and a foam top layer. The middle layer has a plurality of foam pads defining independent support zones of varying densities. The plurality of foam pads are separated by a plurality of channels such that a transfer of force by pressure on one foam pad to an adjacent foam pad is limited. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    These and other aspects and advantages will be described in detail with reference to the accompanying drawings, in which: 
           [0015]      FIG. 1  is a first perspective view of the support surface described herein; and 
           [0016]      FIG. 2  is an alternative perspective view. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]    With reference to  FIGS. 1 and 2 , a support surface or pad  10  suitable for use with a stretcher is constructed of a plurality of foam layers. A base layer  12  is preferably formed of HR (high resiliency) foam (e.g., 1″ thick) for substantial deep support. An open cell foam middle layer  14  is supported on the base layer  12 , and a top layer  15  preferably formed of a visco-elastic foam material (so called “memory foam”) may be disposed over the middle layer  14 . 
         [0018]    The middle layer  14  includes a plurality of foam pads that define independent support zones of varying densities. As shown, the plurality of pads define a head section  16 , a body section  18 , and a foot section  20  separated by a plurality of lateral channels  22 . In a preferred arrangement, the lateral channels  22  extend through the respective sections or “foam support zones”  16 ,  18 ,  20  to the base layer  12 . The foam support zones  16 ,  18 ,  20  may additionally include a longitudinal channel  24  dividing the head  16 , body  18 , and foot  20  sections into left and right side head, body and foot sections as shown. The longitudinal channel preferably also extends through the support zones  16 ,  18 ,  20  to the base layer  12 . 
         [0019]    In a preferred construction, densities of the foam support zones vary by section  16 ,  18 ,  20 . That is, the density of the head section  16  is preferably lower than the density of the body section  18 , and the density of the foot section  20  is also preferably lower than the density of the body section  18 . Moreover, the density of the foot section  20  is preferably lower than the density of the head section  16 . The head  16  and foot  20  sections are generally softer than the body section  18  since the head and heels exert a higher pressure on the support surface  10 . 
         [0020]    With continued reference to  FIG. 1 , the body section  18  includes an upper body section  18   a,  a middle body section  18   b  and a lower body section  18   c.  Densities of the foam support zones in the upper  18   a,  middle  18   b  and lower  18   c  body section preferably also vary by section. The variances in the zones/sections of the stretcher have been specified in an attempt to manage the anatomic characteristics of the average human body. An example would be that generally the sacral and scapulae carry the bulk of the weight in a back lie orientation. These areas therefore require a stackup that reacts(supports the body) quicker than the upper thigh for instances which can be allowed to sink deeper before the real support layers begin to hold the body more substantially. 
         [0021]    As shown, the head section  16  is formed of a foam block  26  having a lateral slot  28  parallel to the lateral channels  22 . The lateral slot  28  in the foam block  26  of the head section  16  preferably extends about halfway into the foam block  26 . The foam block  26  is preferably formed of a soft foam treated with tighter shallower cuts to create initial very soft immersion. That is, when cuts are made into the top of a foam block, the surface between the cuts collapse easier than the same type of foam without the cuts. Additionally, the amount of space between the cuts contributes to the overall softness/firmness of that particular area. Deeper closer cuts are softer than shallow widely spaced cuts. 
         [0022]    The body section  18  includes a plurality of foam blocks  30  (six shown in  FIGS. 1 and 2 , preferably about 3″ thick progressively supportive foam pads) separated by body lateral channels  22 ′ parallel to the lateral channels  22  separating the head section  16 , the body section  18  and the foot section  20 . The foot section  20  is constructed of a foam block  32  having at least one lateral slot  34  therein parallel to the lateral channels  22 . As shown in  FIGS. 1 and 2 , the foam block  32  of the foot section  20  is provided with two lateral slots  34 . The lateral slots  34  are shown in a keyhole shape to facilitate a downward orientation of the foot section  20  relative to the body section  18 . That is, the foot section  20  preferably slopes downward in an arc from the body section  18 . The downward slope serves to shift heel pressure toward the patient&#39;s calves, resulting in increased comfort. Additionally, the lateral slots  34  serve to better distribute pressure in the patient foot area. The foot section  20  foam allows excellent immersion. 
         [0023]    The assembly may additionally include a top cover formed of a suitable material such as 4-way stretch polycarbonate and a bottom cover formed of a suitable material such as non-slip vinyl (not shown) surrounding the support surface. 
         [0024]    In use, the lateral channels  22 ,  22 ′ and lateral slots  28 ,  34  along with the longitudinal channel  24  serve to break tension through the supportive layers and create independent/separate progressively supportive pressure displacement areas across the entire length and width of the support surface  10 . The foam support zones address load requirements (firmness and support characteristics) to localized areas of the pad  10 . The top layer  15  provides an excellent interface and relaxed continuity to the underlying support pads. The base layer  12  provides a firm foundation of support and continuity to the pad. The channels and slots additionally provide for better air circulation within the pad, resulting in a cooler and more comfortable surface. 
         [0025]    While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.