Patent Publication Number: US-6907632-B2

Title: Tactical stretcher

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to stretcher type devices used to transport accident victims, in particular, to stretcher type devices used to transport injured victims who have been exposed to hazardous materials. 
     The transportation of injured victims exposed to hazardous materials poses unique challenges for emergency service personnel. The victim must be removed safely and quickly from the area of the hazardous material. Then, the victim must be decontaminated. The purpose of decontamination is to remove the hazardous material from the exposed victim and to dilute the chemical to the point where it no longer poses threat of injury or harm to an individual. Finally, the victim must be transported to appropriate medical treatment facilities by ambulance, helicopter, or other appropriate means. 
     Current procedures require that an exposed, injured victim be moved from the location of exposure to a decontamination point using a stretcher type device. At the decontamination point, the victim may be transferred to a decontamination table. Following decontamination, the victim is transferred to a second uncontaminated stretcher type device. 
     Although attempts have been made to decontaminate an injured victim without the necessity of transferring the victim to a decontamination table and/or a second uncontaminated stretcher type device thereafter to reduce further injury, further improvements in prior art stretcher designs are still needed to meet this desire. 
     SUMMARY OF THE INVENTION 
     The stretcher of the present invention meets this need. It eliminates the need to transfer a patient from a first stretcher to a decontamination table and/or a second uncontaminated stretcher type device. The stretcher of the present invention is made of materials which do not react with hazardous materials and which may be easily decontaminated when the patient is decontaminated. Additionally, the stretcher of the present invention has fewer parts than similar prior art stretchers, thereby reducing the number of unions or joining points at which contaminates may reside and/or enter into the interior of the stretcher&#39;s frame. Having fewer joining points therefore reduces the difficulty of decontaminating the stretcher. Furthermore, reducing the number of parts increasing manufacturing efficiency by reducing cost and the amount of assembly required. 
     In one embodiment of the invention provided is a folding stretcher comprising a frame constructed of a pair of tubular poles, spreader assemblies connected between the poles for securing the stretcher in a folded or unfolded position, the folded position having reduced width. Swedged handles are integrally formed at ends of the poles. A bed is attached to the poles by a sleeve at each side of the bed. 
     In another embodiment of the invention provided is a folding stretcher comprising a frame constructed of a pair of tubular poles and having a chemical resistant finish. Spreader assemblies are connected between the poles for securing the stretcher in a folded or unfolded position, the folded position having reduced width. Stirrups are provided to the poles. Hinges are provided at the middle of each pole&#39;s length. The hinges are adapted to reduce the length of the frame by half. Swedged handles are integrally formed at ends of the poles. A bed having restraint straps is attached to the poles by a sleeve at each side of the bed. 
     In still another embodiment of the invention, a process of decontaminating an injured person contaminated by exposure to a hazardous material at a contaminated site is provided. The method comprises placing the contaminated person on a stretcher having a frame constructed of a pair of tubular poles, spreader assemblies connected between the poles for securing the stretcher in a folded or unfolded position, the folded position having reduced width. The stretcher further includes swedged handles integrally formed at ends of the poles, and a bed attached to the poles by a sleeve at each side of the bed. The method further comprises transporting the contaminated person to an area away from the contaminated site and free of hazardous material, and decontaminating the contaminated person with water or other decontaminating solvents appropriate to the specific hazardous material while the contaminated person is on the stretcher. 
     These and other features and objects of the present invention will be apparent in light of the description of the invention embodied herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following detailed description of the embodiments of the present invention can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which: 
         FIG. 1  is a top view of one embodiment of a stretcher frame according to the present invention in a substantially unfolded position. 
         FIGS. 2   a  and  2   b  are exterior and interior side views, respectively, of one embodiment of a stretcher frame according to the present invention in an unfolded position. 
         FIG. 3  is an end view of one embodiment of a stretcher frame according to the present invention in an unfolded position. 
         FIG. 4  is a view of a portion of one of the poles of a stretcher frame according to the present invention showing a swedged handle. 
         FIG. 5  is a bottom view of one embodiment of a stretcher according to the present invention in a fully unfolded position. 
         FIGS. 6   a  and  6   b  are top and side views, respectively, showing half of a hinge according to the present invention for the stretcher poles. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION 
     It is noted that the drawings of the invention are not to scale. The drawings are intended to depict only typical embodiments of the invention, and therefore should not be considered as limiting the scope of the invention. 
     By “hazardous materials” we mean materials such as hazardous, dangerous, or unsafe chemicals, radioactive or poisonous elements, human body fluids, chemicals constituting a fire hazard, when appropriate, chemicals used to decontaminate victims, such as a weak acid wash used to decontaminate victims contaminated with an alkaline solution, and the like. 
       FIG. 1  shows the top of one embodiment of a folding stretcher frame  10  in a substantially unfolded position.  FIG. 1  shows two pairs of tubular poles  15  with integral handles  20 . Each pair of poles  15  is connected with hinges  25 , such that they may be folded in half to make the stretcher frame more compact for transporting and storage. The pairs of poles  15  are connected to each other with spreader assemblies  30 . The spreader assemblies  30  include spreader bars  35  pivotally attached at one end to poles  15  and pivotally attached at the other end to coupler  40 . The spreader assemblies  30  are positionable in either a folded compact position that situates poles  15  substantially together or an extended position that spreads poles  15  apart and holds the stretcher frame  10  in a fully unfolded position (FIG.  5 ). 
       FIGS. 2   a  and  2   b  show outside and inside side views, respectively, of the stretcher frame  10  of FIG.  1 . The poles  15  are connected by hinge assembly  25 . Each pole  15  has an integral handle  20 . There are stirrups  45  attached to each tubular pole  15  between the hinges  25  and the integral handle  20 . It is to be appreciated that the stirrups  45  act as feet which support the stretcher frame  10  above a surface when the stretcher is placed on the surface. The stirrups  45  are rotatably attached to the poles  15 , via pins  29 , such that when the stretcher frame is not used in the illustrated fully extended position, the poles  15  may be turned inward such as illustrated by  FIG. 3 , positioning pins  105  of hinges  25  substantially downwards, thereby permitting the stretcher frame to fold in half for storage. 
     In the embodiment illustrated by  FIG. 2   b , the stirrups  45  are attached to poles  15  via bolts  27 . Bolting the stirrups  45  to poles  15  permits the stirrups  45  to be unbolted and removed, thereby conveniently facilitating the slipping off the poles  15  a stretcher bed  60  ( FIG. 5 ) when worn or damaged, and also the slipping on the poles  15  a replacement bed. A more detailed discussion regarding the stretcher bed  60  is provided in a later section in reference to FIG.  5 . 
     In an alternative embodiment, the stirrups  45  are made fast to the poles  15 , such as by welding, and the spreader assemblies  30  are removably attached thereto, such as via bolting. In this embodiment, the bed  60  may also be conveniently slipped off the poles  15  and replaced by removing the spreader assemblies  30 , and folding the stirrups  45  compactly against the poles  15 . 
       FIG. 3  shows the end of the stretcher frame  10 . Each spreader assembly  30  includes spreader bars  35  that are pivotally attached at one of their ends to poles  15 . The other ends of the spreader bars  35  are pivotally attached to a coupler  40 . This pivotal attachment of each spreader assembly  30  allows the stretcher frame  10  to be collapsed width-wise so that the poles  15  are next to each other in the collapsed position. 
       FIG. 4  shows a portion of one of the poles  15  with the integral handle  20 . Integral handle  20  is formed by swedging, or crimping, the end of pole  15 . Swedging forms alternating grooves  50  and ridges  55  of the integral handle  20 . The grooves and ridges allow a person who is lifting the stretcher while wearing heavy rubber gloves to obtain a secure grip. In one embodiment, each handle  20  is formed in such a manner which leaves an opening at the end of the pole  15 . This opening is then sealed with an end plug (not shown). In another embodiment, the end of the pole  15  is fully sealed by the forming process, thereby eliminating the need for an end plug. In order to make a swedged fitting, the terminal end of the tube is squeezed between two swedging members to form the desired shape. 
     Because the handle is formed from the end of the pole, no fasteners are needed to attach each handle  20  to its respective pole  15 . Therefore, the integral handle  20  of the present invention cannot fall off. With handles attached using fasteners, such as with conventional stretchers, if the fasteners fail, the handle could fall off, and the stretcher could be dropped, injuring the patient. In addition, fewer parts are necessary to make the stretcher with swedged handles  20 , thereby reducing the complexity and cost of manufacture. Furthermore, without having a handle to attach to the ends of the tubular members, decontamination is less extensive as there is no seam with the swedged handle  20  at the grip and pole interface as there is in other prior art tactical stretchers. 
       FIG. 5  shows a bottom view of a stretcher  58  comprising the stretcher frame  10  in the unfolded position with the stretcher bed  60  attached. The stretcher bed  60  is made of fabric woven in the form of large honeycomb net. Fabric suitable for decontamination typically has about 40% of the surface area open to allow liquid to pass through; however, materials with 10% to 90% of the surface area open to allow liquid to pass through are also suitable for use. 
     The bed material is made of strong, flexible, flame-retardant, and UV protected monofilament polypropylene fibers which are resistant to hazardous materials, fire, and UV light. Flame retardant properties may be obtained by including in the monofilament polyopylene fibers 13% PT Conc.33, from Mammoth Plastics. UV light protection may be obtained from the inclusion of carbon black in the monofilament polypropylene. The bed fiber preferably is continuous monofilament polypropylene which is woven into a honeycomb and 3/3 broken twill. Polypropylene monofilament is suitable for use in stretcher beds because it is resistant to hazardous materials, fire, and UV light. Other bed fibers that may be suitable to a greater or lesser degree include, but are not limited to, polyester, polyamides, and a blend of polyester and polyamide. 
     Loops  65  are formed along the length of the stretcher bed  60  on each side and are used to receive the tubular poles  15 . Each loop  65  is form by a hem  70  running along the length of each side of the stretcher bed  60 . The hem may be formed by cuffing or rolling the sides of the bed material through out the length of the stretcher bed  60 . The stitching is typically double needle locking with polyester thread. Other threads may be used, such as polyamides, or blends of polyester and polyamides. The hem may be reinforced with a reinforcing ribbon sewn into the hem using stitching. Using the reinforcing ribbon with the hem makes it possible to use the honeycomb mesh throughout the width of the stretcher bed. Hemming without a reinforcing ribbon may result in a hem without adequate strength to support patients. Using a hem with a reinforcing ribbon allows a more open stretcher bed, which aids the decontamination process. 
     The alternative reinforcing ribbon and the straps are made of the same materials as the fibers of the bed material. The reinforcing ribbon may differ from the bed material in that it is closely woven as opposed to being woven in a honeycomb net or mesh. A suitable material for the reinforcing ribbon is monofilament polypropylene in a 3/3 broken twill weave or a trampoline style weave. Alternatively, the reinforcing ribbon may be a non-woven solid webbing of monofilament polypropylene or other materials suitable for the bed. Use of the reinforcing ribbon when desired provides additional strength to the hemming of the honeycomb net or mesh stretcher bed. 
     There are two restraining straps  75  for retaining the patient on the stretcher. The straps  75  may be attached to the stretcher bed  60 . Alternatively, the straps could be attached to the tubular poles  15  by a fastener. The straps  75  may be made of suitable strong, hazardous material-, fire-, and UV light-resistant materials, such as 3/3 broken twill monofilament polypropylene and materials suitable for the bed. 
     When a patient is on the stretcher  58 , the ends of the straps  75  are connected by buckles  80 , thereby securing the patient to the stretcher. The buckles  80  can be side release buckles, which allow easy use with heavy gloves. Other types of closures may be used, including, but not limited to hook and loop closures, and other buckle arrangements. Each buckle  80  can be made of polypropylene which is resistant to hazardous materials. Other materials may be used such as metals coated with chemical resistant paint, chemical resistant metals, polyamide, polyester, high-density polyethylene, and acrylic. 
     As shown by  FIG. 5 , the stretcher bed  60  further has a cutout  85  surrounding each hinge  25  to allow operation of the hinges  25  without interference from the stretcher bed  60 . A similar cutout  86  is also provided around each stirrup  45  for the same purpose. With regards to each hinge,  FIGS. 6   a  and  6   b  show half of hinge  25  which can be used in the present invention. The hinge  25  includes a pole insert portion  90  and complimentary jaws-shaped members  95 . The pole insert  90  is inserted into pole  15  shown in dotted lines. The pole insert  90  can be attached to pole  15  by any suitable means, such as threads, crimping, welding, or using a sealing material. The complimentary jaws-shaped members  95 , which are best shown by  FIG. 1 , are pivotally attached together by pin  105 . The hinge  25  only folds in one direction, thereby allowing the stretcher to be collapsed, reducing the length by approximately one half to facilitate storage and transportation of the folded stretcher  58 . It is to be appreciated that hinge  25  opens outwardly and that teeth  110  ( FIGS. 6   a  and  6   b ) of each jaws-shaped member  95  mesh with their counterpart member  95  when the hinge is closed. As best illustrated by  FIG. 2   a , the teeth  110  of the hinge  25  are horizontally orientated parallel to each other when situated together, thereby adding strength and rigidity of the tubular pole  15  when the stretcher  58  is used to support or carry a person. To unlock the hinges  25 , the spreader bars  35  are first partially folded as illustrated in  FIG. 1 , then the stretcher poles  15  are both rotated 90° as shown in FIG.  3 . The rotation turns the hinges  25  to a position where they can open, allowing the stretcher  10  to then fold in half, which is indicated by the arrows shown in  FIG. 2   a.    
     The tubular poles  15  and other elements of the stretcher frame  10  may be constructed of a strong, light metal, including, but not limited to aluminum, titanium, steel, copper, and alloys of these metals. The stretcher frame  10  may be coated with a chemical resistant paint to protect it from hazardous materials and weathering. A typical chemical resistant paint is polyurethane. Other chemical resistant paints may be used, including, but not limited to, epoxy, hybrid, or polyester paints. 
     The decontaminatable stretchers of this invention may be used as any conventional folding or folding and collapsible stretcher. The stretcher  58  of the present invention may be used to transport a contaminated patient from a contaminated environment, the patient may be decontaminated while on the stretcher, and the stretcher may be used to transport the patient from the contaminated environment to a medical facility. The decontamination process used to decontaminate the patient is spraying, washing, or blotting the patient with water, detergent solution in water, or other required chemical decontaminate solutions. This also serves to decontaminate the stretcher  58 . 
     Use of the present stretcher  58  has the advantage of eliminating the current need to transfer the patient from the first contaminated stretcher to a decontamination table and/or a second stretcher type device or backboard at the decontamination site. This reduces the chance of additional injury or aggravation of previous injuries to the patient while also reducing the time required for the decontamination process. In addition, the present stretcher  58  with fewer joined parts reduces the risk of hazardous materials remaining with the stretcher after decontamination. Use of the present stretcher  58  therefore avoids the delay and potential injury associated with the decontamination process and transferring a patient from one support to another, and avoids the cost of additional stretchers or backboards. 
     While certain representative embodiments and details have been shown for purposes of illustrating the invention, it will be apparent to those skilled in the art that various changes in the compositions and methods disclosed herein may be made without departing from the scope of the invention, which is defined in the appended claims.