Abstract:
A bariatric adapter for a portable patient-transport gurney provides a wider, secure and comfortable surface for carrying larger patients. The adapter may be constructed in multiple segments so that adjustments of the gurney (e.g., elevating head/torso support or leg supports) can still be used. The adapter does not require modifications to the gurney, so it can be removed when not needed. However, smaller patients may also find the wider bed more comfortable, so it may be left attached for all users.

Description:
CONTINUITY AND CLAIM OF PRIORITY 
       [0001]    This is an original U.S. patent application. 
       FIELD 
       [0002]    The invention relates to medical transportation equipment. More specifically, the invention relates to adapters to extend the bariatric-patient carrying capacity of existing stretchers, cots and gurneys, and to improve the comfort of all patients being transported. 
       BACKGROUND 
       [0003]    Equipment for transporting injured, sick or disabled people is subject to a variety of design constraints that are often in conflict. For example, a patient&#39;s injury may be exacerbated if the patient cannot be held securely in a particular position or orientation, but the adjustability to permit such secure transport may make the equipment heavy or bulky, so that it cannot be maneuvered from place to place, or may require a larger team of attendants to operate and move it. Imposing the further requirements that the equipment be rugged, relatively lightweight, and that it not occupy an excessive proportion of the limited space available in an emergency vehicle, results in serviceable but constrained designs. 
         [0004]    One challenge emergency medical responders are encountering more frequently is that of dealing with larger patients (regardless of whether those patients meet the medical definition of obesity). The portable gurneys used to carry patients to and from an ambulance may have service weight limits of 700 pounds (318 kg), but a typical gurney is only 23 inches (58 cm) wide—much too narrow to carry a 500 pound (230 kg) patient, even though such a patient would not exceed the weight limit. The alternative is to deploy a special bariatric-patient gurney, but these contraptions are much more expensive, heavier, and often must be used with ramp and winch systems, which embarrass and humiliate the patient by treating him as a “wide load” to be yarded around with heavy equipment. 
         [0005]    An adapter to improve the bariatric-patient handling capacity of a standard gurney may extend the usefulness of such a gurney, and do so without requiring permanent modifications thereto. In addition, features to suit the adapter to use in an ambulance or medical services van may allow an ordinary EMS vehicle and crew to serve a wider range of patient sizes with care, comfort, security and dignity. 
       SUMMARY 
       [0006]    Embodiments of the invention enlarge the horizontal carrying surfaces of a portable gurney (cot, stretcher) to accommodate larger patients (those whose weight is below the service limit of the gurney, but whose bulk makes use of the gurney alone unstable or uncomfortable). Features of the invention allow it to be attached to the gurney when needed (and removed when not needed) so that the gurney&#39;s normal configuration and function are not affected. Furthermore, an embodiment may be stored securely when not in use, without consuming excessive space in an ambulance or other emergency-services vehicle. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0007]    Embodiments of the invention are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean “at least one.” 
           [0008]      FIG. 1  shows a simplified gurney with an embodiment of the invention partially installed thereon. 
           [0009]      FIG. 2  shows a top perspective view of a sample embodiment of the invention. 
           [0010]      FIG. 3  shows a bottom perspective view of the sample embodiment of the invention. 
           [0011]      FIG. 4  is a perspective view of an anti-shift peg (shown inverted from its usual position). 
           [0012]      FIG. 5  is a cross-section view of an anti-shift peg, also showing a portion of the box section of an embodiment and a portion of the patient-support surface of a standard gurney. 
           [0013]      FIG. 6  is an exploded view of one segment of an embodiment. 
           [0014]      FIG. 7  shows a mounting panel for attaching an embodiment to an EMS vehicle when not in use. 
           [0015]      FIG. 8  is a flow chart outlining a method for preparing an embodiment of the invention for use. 
           [0016]      FIG. 9  shows a cross section of bolsters and mattress pad. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    Embodiments of the invention are planar adapters that increase the size (surface area) of the patient bed of a portable gurney. The adapters are designed to work with popular EMS (“Emergency Medical Services”) equipment and to improve the security and comfort of larger patients being transported on such a gurney. In addition, the adapters have features that improve their function and utility in the context of emergency-response medical service. 
         [0018]      FIG. 1  is a simplified overview drawing showing a sample standard gurney  100 , comprising inter alia a wheeled frame  110 , a scissor-action mechanism  120  for raising and lowering the patient, a frame  130  and three adjustable segments: head support  140 , abdomen support  150  (mostly obscured in this view) and leg support  160 . Hook-and-loop fasteners are visible on head and leg supports at  145  and  165 ; in use, a padded mattress would normally be placed on the supports and secured with these fasteners. Note that the patient-support surfaces of this standard gurney have regular perforations (e.g.,  148 ) to reduce weight and improve air circulation. 
         [0019]    An actual gurney would be somewhat more complex than this figure suggests: it may have power or hydraulic lifts, wheel locks, IV stand supports, or other features that are not of consequence to embodiments of the invention. 
         [0020]      FIG. 1  also shows an embodiment of the invention, including a head/torso support section  170 , an abdomen support section  180  and a portion of a lower-extremity support section  190 . Head/torso support section  170  is shown displaced vertically from its normal installed position, while abdomen support section  180  is shown installed, and lower-extremity support  190  is installed, but several subcomponents are omitted in this view to allow the following points to be observed: 
         [0021]    First, the sections of an embodiment are generally wider than the corresponding patient support surfaces of the standard gurney. For example, a standard gurney may be roughly rectangular, with a width of approximately 23 inches (58 cm) and a length (fully extended) of approximately 80 inches (203 cm). Embodiments may be somewhat wider, at perhaps 26 inches (66 cm), up to perhaps 36 inches (91 cm). A wider surface is preferable from a patient comfort perspective, but the gurney and attachment must still pass easily through standard doors. For this reason, a width less than the common door width of 30 inches (76 cm) is preferred. 
         [0022]    However, note that the upper and lower ends of the embodiment are tapered, and may be no wider than (or even narrower than) the standard gurney at the ends. Extra width at these locations contributes little to patient comfort, while the tapers may significantly improve the maneuverability of the gurney around corners and through doorways. The overall length of an embodiment may be approximately the same as the length of the standard gurney for which it is designed. 
         [0023]      FIG. 1  also shows several of the side bolsters that are present in an embodiment ( 173 ,  176 ,  183  and  186 ). These bolsters may be made of a firm, resilient material such as a dense polyurethane foam, preferably covered by a tough, waterproof material such as a marine-grade vinyl. 
         [0024]      FIG. 2  is a top perspective view of a representative embodiment of the invention. This embodiment includes three independent segments: a head/torso support segment  270 , an abdomen support segment  280 , and a lower-extremity support segment  295 . Each segment is constructed similarly, with an upper support sheet (e.g.  291 ) of a material such as aluminum, steel or plastic plate; secured to a tubular frame (e.g.  290 ) that surrounds and substantially follows the perimeter of the upper support sheet. Each segment has pads or bolsters  273 ,  283 ,  293  at each lateral side, oriented lengthwise along the patient support surface. The head/torso segment  270  and lower-extremity segment  295  include portions (e.g.,  292 ) where the top sheet is cut away from the tubular frame, exposing the frame to be used as a hand-hold for steering the gurney. In addition, each segment has an opening (e.g.,  297 ) in the top patient-support surface through which a securing belt (attached to the standard gurney below) may be passed. 
         [0025]    The embodiments of  FIGS. 1 and 2  are constructed in three separate sections because the standard gurney for which they are designed has independently-adjustable head and foot sections. (A center section is also present on some standard gurneys; this section may also be adjustable.) The head section may be raised to allow the patient to sit up, or the foot may be raised to help improve patient circulation and/or increase blood pressure. By constructing the bariatric adapter in corresponding sections, each section can be attached to its corresponding segment of the standard gurney, and the standard gurney&#39;s adjustment features will still function normally. A simpler embodiment consisting of a single segment, but constructed similarly to what is described below, may be less expensive to make, but is less useful (it may prevent adjustments that the standard gurney is capable of, and may be less convenient to store when not in use). 
         [0026]      FIG. 3  is a lower perspective view of the embodiment of  FIG. 2 . The three sections  270 ,  280 ,  295  are visible, as are the side bolsters  273 ,  283 ,  293 , tubular frame  290  and portions of the underside of the upper support sheet  291 . However, this view is dominated by the three box-section support structures  300 ,  310  and  320 , which are attached to the corresponding tubular frames and top sheets. The box-section supports provide strength and rigidity to each segment, allowing the segment to support a portion of the patient&#39;s weight and to transmit the force effectively to the standard gurney below. The box sections may be made from folded and welded sheet metal material such as aluminum or steel, molded from a suitable polymer, or laid up from a fiberglass or carbon-fiber material. The choice between these materials may be made based on availability, durability, price, weight, and other considerations, in the exercise of ordinary engineering judgment. 
         [0027]    Each segment of the bariatric adapter is designed to rest upon a corresponding portion of the standard gurney. However, it is essential that the adapter not shift or slide relative to the gurney surface, lest the gurney tip over or the patient be dropped. Embodiments of the invention resist shifting or sliding by using anti-shift features that are visible in  FIG. 3 : each of the circular posts or pegs (one of which is circled at  330 ) is positioned so as to mate with a depression or hole in the upper surface of the standard gurney. When so mated, the pegs resist shifting forces, which are experienced locally as shear stresses. 
         [0028]    Some embodiments may include openings on the angled sides of the box-section supports, as shown at  370 ,  380  and  390 . The purpose of these openings will be discussed below. 
         [0029]      FIG. 4  is a detail view of one implementation of anti-shift peg. This figure shows the peg upside clown from its normal orientation on the underside of a box section support. The peg is generally cylindrical, with a largest-diameter portion  410  that spreads compression and torque forces over a larger area of the box section. Each adapter section is spaced apart from the underlying gurney surface by approximately the thickness of  410  and a resilient flange or washer  420 . Flange  420  may be made of a material like rubber or neoprene, and may be sandwiched between  410  and  440 , or may simply rest upon  410  (reference character  430  shows that it may be possible to lift flange  420  off the lower ledge, for example, to replace the flange. The resilient material provides padding between the lower surface of an embodiment and the upper surface of the standard gurney, to accommodate slight misalignments between the two surfaces, and to prevent excessive wear on the gurney upper surface clue to concentration of forces around the anti-shift pegs. 
         [0030]    A smaller-diameter portion  440  forms the peg that mates with a corresponding hole or depression in the standard gurney patient-carrying surface, and bears any shear forces that act to slide the adapter segment horizontally across the gurney surface. A tapered or beveled end portion  450  makes it easier to align the adapter segment with the holes or depressions in the gurney surface; and if the gurney has depressions (rather than holes), the bevel may allow secure, complete seating despite debris that may be in the gurney depression. A screw or bolt  460  may be used to secure the anti-shift peg to the bottom of the box-section support, as discussed below. 
         [0031]      FIG. 5  shows a cross-section of an anti-shift peg (generally  400 ) attached to a box-section support (cross section  510 ) by screw or bolt  460 . The differing diameters of the peg  410  and pad  420  are visible here, and it can be seen that box-section support  510  is spaced apart from the patient-carrying surface of the gurney,  520 , by the thickness of  410  and  420 . Holes in the patient carrying surface of the gurney often have formed, radiused edges as shown at  530  to increase the strength of the surface. 
         [0032]    Referring again to  FIG. 3 , note that this embodiment has two threaded receptacles ( 340 ,  350 ,  360 ) in each box section support to accept a screw inserted from below the standard gurney surface. The screws (which preferably have large, finger-operable knobs on their ends) hold the adapter against the standard gurney surface, keeping the anti-shift pegs engaged in their corresponding holes. Other embodiments may use a solid rod extending from the bottom of the adapter, through the standard gurney upper surface and secured by a hairpin cotter clip or “R-clip,” or a pivoting claw-type latch that grasps a frame rail of the standard gurney. 
         [0033]    Note that the lower box-section support raises the bariatric adapter frame above the surface of the standard gurney by approximately the height of the box section (plus, inter alia, the thickness of the largest-diameter portion of the anti-shift peg and the rubber flange or washer, as discussed above). The box section height is preferably chosen so that the tubular frame of the adapter rests upon frame rails or hand rails of the standard gurney, to distribute the weight of the patient more effectively across the support surfaces of the gurney. 
         [0034]      FIG. 6  is an exploded view of the head/torso section of an embodiment of the invention. This view shows the tubular segment frame  630 , top support sheet  640 , box-section lower support  600 , and side bolsters  673  and  676 . The top sheet, frame and lower support may be joined together by welds, adhesive, or rivets (as suggested by the holes shown in this figure). Several disassembled anti-shift pegs are visible, and a threaded T-nut (or flanged nut) structure identified at  650  may be attached to the box-section lower support to accept the releasable engagement screws that hold the segment to the corresponding portion of the gurney. Note that the box section support, when covered by the top sheet, forms a hollow compartment. A door or covering  645  may be provided in the top sheet to access this compartment. This may provide useful storage for adapter accessories, such as patient safety belt extensions or extra securing screws. 
         [0035]      FIG. 7  shows a mounting panel that may be supplied with an embodiment to facilitate storage of the embodiment segments on a side wall of an ambulance or EMS vehicle when the embodiment is not in use. Segments of an embodiment can be hung against the wall where they take up little space and do not interfere with patient-care activities inside the vehicle. 
         [0036]    The hanger (generally  700 ) is a mostly-planar sheet  710  with two horizontal channels  720  and  730  raised above its surface. Upper channel  720  may be smaller, since it only needs to provide relief for threaded fasteners (nuts, etc.) installed behind sheet  710 . Lower channel  730  extends further out from the base plane, and mounting features similar to (or in some embodiments, identical to) the anti-shift features on a patient support segment are attached to its upper surface ( 740 ). These mounting pegs mate with corresponding holes in the box-section support of a segment (see, e.g.,  FIG. 3 :  370 ,  380  and  390 ), and provide vertical support for the segment. Horizontal support to keep each segment from falling off the hanger may be provided by bolts or similar fasteners, which may be secured to the threaded fasteners at  750 . In this figure, two patient support segments  270  and  280  are shown in place, and held against the hanger by finger-manipulable fasteners  760  and  770 . Since the lower channel  730  extends further out from the mounting plane, an embodiment may use the space in the channel for storage, by providing an opening or door  780 . 
         [0037]      FIG. 8  outlines steps involved in preparing an embodiment for use. To transport a large patient, the attendants may extend or flatten the bed of the standard gurney ( 810 ) and remove the mattress pad (typically by disengaging hook-and-loop fasteners) ( 820 ). Next, segments of the embodiment are disengaged from the carrier or mounting brackets ( 830 ), and each segment is mated to its corresponding gurney section by inserting the anti-shift pegs into the depressions or holes ( 840 ). Then, the segments are secured in place by engaging the threaded fasteners, inserting R-clips, latching the pivoting-claw latches, or activating such other locking mechanisms as may be provided with the embodiment ( 850 ). Now, patient-securing belts are fed through the openings in the embodiment segments, so that the patient can be strapped in if necessary ( 860 ). Finally, the mattress pad is replaced on top of the segments of the embodiment ( 870 ). Note that because the patient-carrying surfaces of an embodiment are displaced slightly from the surfaces of the standard gurney, they will move differently when the head and/or foot sections are adjusted. For this reason, it is preferable to secure the mattress pad on only one end (otherwise, the pad may crease or bunch up). Preferably, an embodiment has a hook-and-loop fastener only on the lower-extremity support segment; the middle and upper end of the mattress pad is left free to slide up as the head/torso support section is adjusted. 
         [0038]      FIG. 9  is a cross-section showing a preferred relationship between the bolsters  983 ,  986  of an embodiment and the mattress pad  910  of a standard gurney, placed over the surface of an embodiment as discussed with reference to  FIG. 8 . Even if a patient&#39;s body (represented here by oval  900 ) is wider than the mattress and bolsters, the higher profile and firmer construction of the bolsters provides a significantly improved feeling of security for the patient. Patients who report feeling like they may roll or slide off a standard gurney (even though, statistically speaking, that is unlikely) prefer being transported on a cot equipped with an embodiment of the invention. 
         [0039]    Features and design details of the present invention have been described largely by reference to specific examples and in terms of particular implementations. However, those of skill in the art will recognize that improved bariatric-patient transport capabilities can also be achieved by adapter designs that implement the goals described differently than the reference embodiments discussed. Such variations and alternate designs are understood to be captured according to the following claims.