Abstract:
The present invention is an apparatus for releasably constricting one or more objects, and in particular to a restricting blood to an injured appendage comprising an elongate band and capture device that cooperate to form a releasable, adjustable loop. A release lever and a parallel thumb mount are compressed to release the elongate band from the capture device, where the thumb mount is configured to remain fixed while the release lever rotates about a fulcrum bar to disengage a projection that locks the size of the loop.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention relates in general to the field of plastic ties, used generally to temporarily bind a plurality of objects, and is especially suited for blood flow restriction (e.g., a tourniquet), in an appendage such as an arm, leg, finger, or toe, quickly and reliably using a simple device that constricts and releases the appendage as required. The release feature of the present invention makes it suitable for more general purposes, and the invention is not limited to any particular use or field. 
         [0002]    Tourniquets are well known for the purpose of temporarily restricting the flow of blood to a person&#39;s injured limb in order to prevent a serious loss of blood. In battle environments, many deaths are attributed to blood loss from extremities as a result of body armor that is applied around the trunk. Death can occur within minutes due to blood loss, so the time needed to apply a tourniquet is critical. Further, it is most advantageous if a tourniquet can be applied by the victim, but self application of a tourniquet has been at best problematic in the past. Most emergency medical technicians and paramedics have belts or cords that can be fashioned into a tourniquet when needed. However, these devices suffer from one drawback or another in that they either require the use of both hands to secure and tighten, or they are difficult to thread about the injured appendage. Further, where the injury occurs in the home or workplace and unskilled persons or the injured party themselves may be required to apply the tourniquet, previous devices and methods do not lend themselves to easy application and secure blood flow restriction. Another disadvantage is that traditional blood flow restriction devices are too large to effectively work on smaller appendages, such as fingers. However, fingers and toes suffer a disproportionately high number of cuts and lacerations, and the loss of blood from these wounds can lead to serious health consequences. 
         [0003]    Presently, a rubber band, Penrose drain, or the finger of a rubber glove is typically used with a clamp to restrict blood flow to and through a finger. The hazard with these solutions is that they tend to roll up as they are stretched, transmitting a high force over a very small area. This concentrated force increases the risk of neurovascular damage. Furthermore, these tourniquets do not allow the amount of pressure being applied for controlling bleeding to be easily modified. As a result, they tend to be applied too tightly, causing undue force on the digit and increasing the risk of neurovascular injury. 
       SUMMARY OF THE INVENTION 
       [0004]    The device used in the present invention is light-weight, sterile, disposable, reliable, and cost effective plastic tie that can be quickly locked and released. While the invention is suitable for many purposes, including those ordinarily associated with Zip Ties, the invention is also well suited for medical applications and can be kept in a first aid kit, a glove box, or purse, for emergency situations. It can also be easily and quickly applied by the victim in a reliable manner. An important feature of the present invention is that the wounded appendage does not have to be moved to apply the device, since it can be slid under the appendage and secured without the need to either lift the appendance or otherwise move it. This feature can be critical if the victim is trapped in a situation where either the victim is immobile or cannot be easily accessed, as is the case in automobile accidents and accidents involving machinery. The present method can also be used in medical procedures and surgeries where the restriction of a blood flow is needed, and can replace more expensive apparatus that performs the same function. 
         [0005]    The present invention is small lightweight plastic tie that can be used to bind objects or as a tourniquet to restrict blood flow in an injured appendage, and can also be used to apply direct pressure to a wound when direct pressure cannot otherwise be applied to the area. This is done by placing gauze on the wound and then gently applying direct pressure with the device. 
         [0006]    Blood flow constricting devices should not ordinarily be left in place for over one hour, as they may cause neurovascular damage. The present invention allows the tourniquet to be released for a time period, and then retightened, mitigating prolonged ischemia risks. Since the device is releasable, the pressure can be titrated and readjusted to provide only the minimum amount of pressure needed. The re-adjustable nature of the device is particularly useful for medical procedures, such as finger lacerations and ingrown toe nails, as these are particularly high vascular areas. The current standard of care is to inject a local anesthetic without epinephrine, as epinephrine has been found to cause tissue necrosis in part of the body. The addition of epinephrine would normally decrease blood flow to an area decreasing the need for a tourniquet, as the area where one would be working could more easily be visualized. However, as epinephrine cannot be used with the local anesthetic, a tourniquet is often needed to decrease bleeding in order to visualize a particular area. A tourniquet needs to be applied to digits (fingers and toes) due to their highly vascular nature. 
         [0007]    The present invention allows for an easy, low cost way to apply the minimal amount of pressure in order to achieve vascular control. The amount of pressure can be increased or decreased easily and more accurately than previous methods using the releasable locking mechanism. In addition, the rigid nature of the apparatus prevents it from rolling up and narrowing the area of applied force, mitigating any potential neurovascular compromise. The present invention is well suited for medical procedures where a tourniquet is required, such as surgeries on the hand, arm, foot, ankle, knee, or other extremities. Once again, the pressure can easily be titrated to obtain the minimal amount of pressure needed. Additionally, it facilitates procedures outside of an operating room as expensive equipment is not needed to obtain vascular control. 
         [0008]    One feature of the present invention is a new release mechanism for the zip tie that includes an inclined lever for engaging the zip tie free end and an inclined thumb mount extending generally parallel to the lever. The thumb mount is spaced from the lever by a gap that allows the lever to be squeezed toward the thumb mount, releasing the zip tie free end. The thumb mount is preferably thicker and has a larger base, such that when the lever and the thumb mount are squeezed together the lever moves toward the thumb mount while the thumb mount is largely fixed. This allows the release mechanism to be grasped between a thumb and forefinger and squeezed, and the lever will withdraw from the engagement with the toothed free end of the zip tie. The angle of the inclined thumb mount enables a more efficient engagement of the lever with the zip tie, since its release is made easier by the presence of the thumb mount. Both the thumb mount and the lever are preferably provided with ridges or grooves to enhance the traction and improve the grip, which can be important when there is blood, sweat, or the presence of other substances which may make the zip tie slippery or difficult to operate. 
         [0009]    Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the features of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a plan view of the present invention used as a blood flow constricting device; 
           [0011]      FIG. 2  is an enlarged, side perspective view of the device of  FIG. 1 ; 
           [0012]      FIG. 3  is a side view of the device of  FIG. 1 ; 
           [0013]      FIGS. 4 and 5  are cross-sectional views of the device of  FIG. 1 ; 
           [0014]      FIG. 6  is an elevated perspective view of the invention used in a non-medical application; and 
           [0015]      FIG. 7  is a front view of the thumb mount and release lever. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0016]    For a better understanding of the present invention together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the above described drawings.  FIG. 1  illustrates a releasable cable tie  10  of the present invention which operates in a manner such as certain cable ties offered for construction applications like those offered by KAI SUH SUH Enterprise Co., Ltd., as shown at http://www.allproducts.com/ee/kss/cable_tie.html. The cable tie  10  may be made from Nylon or plastic which has sufficient rigidity to prevent the tie from folding or rolling as pressure is applied, although any suitable material can achieve the objectives of the present invention. The cable tie  10  may be a single use application where the tie is sterile and enclosed in a sealed package until its ready for use, although in non-medical applications (see  FIG. 6 ) the tie can be reusable and non-sterile. 
         [0017]    The cable tie  10  includes a free end  12  in the form of an elongate band that preferably includes a flat, smooth surface  13  on one side and closely spaced, traverse ridges/grooves  14  on the opposite side extending laterally across the band  12  in regular intervals. The distal end  16  of the tie  10  may have a rounded tip to facilitate insertion through the capture mechanism at the proximal end  20  of the tie  10 . As the distal end  16  of the free end  12  is fed into and through the capture mechanism, the grooves  14  are sequentially engaged by a lever arm  22  at the capture mechanism. The lever arm  22  includes an edge-like tab or projection  24  (see  FIGS. 4 and 5 ), that is preferably wedge shaped, and mates with each groove  14  as the free end  12  passes through the capture mechanism, preventing the free end  12  from being withdrawn back through the capture mechanism. In a preferred embodiment, the wedge-shaped projection  24  is angled like a barb, having an upper surface that forms an acute angle with the free end  12 , strengthening the engagement of the projection  24  with the grooves  14 . This ensures that once the free end  12  is pulled to a particular loop size D, the loop will not release as long as the lever arm  22  is not disengaged from the occupied groove. The grooves  14  on the free end  12  can alternately be replaced by projecting teeth and the lever arm  22  can be adapted with a slot or groove to receive one or more teeth to lock the lever arm in place and fix the free end  12 . 
         [0018]    The capture mechanism includes a C-shaped block  42  where the opening  44  is sized to receive the free end  12  of the tie  10 . A thickness T of the C-shaped block  42  is greater than a thickness t of the free end  12  of the tie  10  to provide a sturdy and aligned entrance for the free end  12 . The C-shaped block  42  is connected to the proximal end  46  of the free end  12  by left and right supports  48  extending from the proximal end  46 . The supports  48  comprise longitudinal components  50  and transverse extensions  52 , where the transverse extensions  52  mate with the ends  57  of the C-shaped block  42  to define a T-shaped opening  44 . The free end  12  of the tie  10  is inserted into the opening  44  along the upper portion, which is sized to snugly receive the free end  12  thereinthrough. 
         [0019]    The longitudinal components  50  of the supports  48  are connected together by a fulcrum bar  56  at the connection of the C-shaped block with the supports  48 . The fulcrum bar  56  mounts a locking mechanism comprising the lever arm  22  and an integral wedge-shaped projection  24  pointing inwardly at the exit of the C-shaped block  42 . The lever arm  22  includes an release extension  66  that is oriented at an angle θ that is approximately thirty degrees (30°) in an unbiased position with respect to a plane defining the ingress and egress of the free end  12  through the upper portion of the opening  54  of the C-shaped block  42 . An downward force (See  FIGS. 4, 5 ) applied to the lever arm  22  at the release extension  66  rotates the lever arm  22  and the wedge-shaped projection  24  about the fulcrum bar  56 , causing disengagement of the wedge-shaped projection  24  from the grooves  14  on the surface of the free end  12 . In this manner, the loop  55  formed by the free end as it is captured by the capture mechanism can be adjusted by positioning the wedge-shaped projection  24  of the lever arm  22  into the correct groove to apply the correct amount of pressure. 
         [0020]    To aid in applying the upward force on the lever arm  22 , a thumb mount  60  is formed on the proximal end  46  of the free end  12 . The thumb mount  60  comprises a thumb plate  62  having a width that is substantially the width of the free end  12 , and may include frictional ridges on a lower surface  69  to improve the gripping characteristics of the thumb mount  60 . The thumb mount  60  is cantilevered to the proximal end  46  of the free end  12  at an angle that orients the thumb mount  60  and the lever arm  22  approximately parallel, i.e., about thirty degrees (30°) from the exit plane of the free end  12  emerging from the capture device. The thumb mount  60  is connected to the free end  12  using a reinforced attachment  68 , whereby a thickness of the intersection of the thumb plate  62  with the free end  12  is approximately twice the thickness of the thumb plate  62 . This added reinforcement ensures that the thumb plate remains essentially fixed while a compressive force is applied to the thumb mount  60  and lever arm  22 , such that the lever arm  22  moves toward the thumb mount  60  and not vice-versa. This ensures that the wedge-shaped projection  24  will disengage with the grooves  14  on the free end when the thumb mount and lever are squeezed together. 
         [0021]    In operation, when the tie  10  is needed to restrict blood flow in an appendage such as a finger  70 , the tie is preferably removed from a sterile packaging and brought in proximity with the patient. With the grooved surface facing upward, the free end  12  of the tie  10  is bent backwards and inserted into the upper portion of the T-shaped opening  44  in the C-shaped block  42  to form a loop  55 . The loop  55  is then placed over the appendage  70  between the wound/surgical location and the victim&#39;s heart so as to be in position to restrict blood flow to the area. The free end  12  of the tie  10  is pulled slowly through the capture mechanism, until the wedge shaped projection  24  of the lever arm  22  engages the first groove  14  on the surface of the free end  12 . As the free end  12  is pulled farther through the opening  44 , each successive groove  14  is engaged by the wedge-shaped projection  24 , such that it withdrawal of the free end  12  is prevented by such engagement. This process establishes the size of the loop  55  and accompanying pressure thereby applied to the finger  70 . The tie  10  is tightened around the appendage  50  until the requisite amount of pressure is applied to restrict the flow of blood to the designated area, whereupon the pulling of the tie is ceased. 
         [0022]    If the flow of blood requires adjusting, the flow can be restricted further by simple pulling the tie  10  one groove  14  at a time until the correct pressure is achieved. If the pressure needs to be lessened, or the device removed, the user places a thumb on the thumb mount  60  and a finger on the lever arm  22 , and applies a compressive force to squeeze the two extensions together. Due to the reinforced thickness  68  at the thumb mount&#39;s connection to the free end  12 , the compression will move the lever arm  22  toward the thumb mount  60  and away from the free end  12 . This movement releases the wedge-shaped projection  24  from its occupied groove  14 , allowing the free end  12  to be withdrawn from the capture mechanism. This process can be repeated as necessary to gradually tighten or loosen the pressure applied by the tie device  10 . 
         [0023]      FIG. 6  illustrates alternative uses for the invention  10 , including binding and gathering various objects, especially elongate objects. The invention is thus not limited to any particular usage, but rather is and should be considered a general purpose tie. 
         [0024]    The method and apparatus just described is illustrative of the present invention, and should not be deemed to be limiting in any manner. Rather, the scope of the invention is properly considered to include all variations and modifications that would be considered by those of ordinary skill in the art. Accordingly, the invention is properly measured not by the aforementioned description but rather by the words of the appended claims and all equivalents attributable thereto.