Self-locking tourniquet and automated timer

Abstract

Embodiments of the present invention relate to a tourniquet tension indicator including a base configured to attach to a tourniquet strap, a platform configured to move relative to the base, a visual indicator configured to provide a variable visible indicator, and an initiator configured to apply a pressure to the visual indicator based on relative lateral motion of the platform to the base.

What is claimed is: 
     
         1 . A tourniquet tension indicator comprising:
 a base configured to attach to a tourniquet strap;   a platform configured to move relative to the base;   a visual indicator configured to provide a variable visible indicator; and   an initiator configured to apply a pressure to the visual indicator based on relative lateral motion of the platform to the base.   
     
     
         2 . The indicator of  claim 1 , further comprising
 a tactile indicator configured to provide a variable tactile indicator based on relative lateral motion of the platform to the base.   
     
     
         3 . The indicator of  claim 1 , wherein
 the platform is configured to move relative to the base when subjected to a lateral tension applied to the base and the platform.   
     
     
         4 . The indicator of  claim 3 , wherein
 the visual indicator is configured to provide the variable visible indicator based on the lateral tension applied to the base and the platform.   
     
     
         5 . The indicator of  claim 1 , further comprising:
 a compressible member disposed substantially in-plane with the platform, wherein
 the compressible member is configured to resist movement of the platform relative to the base when lateral tension is applied to the base and the platform and the tourniquet strap is tightened around a limb. 
   
     
     
         6 . The indicator of  claim 5 , further comprising:
 a tactile indicator configured to provide a variable tactile indicator based on relative lateral motion of the platform to the base.   
     
     
         7 . The indicator of  claim 1 , wherein:
 the visual indicator comprises a reservoir, a timing strip, and a seal between the reservoir and the timing strip; and   the initiator comprises a moveable roller that is configured to move vertically in response to relative lateral motion between the platform and the base, and to apply a pressure to the reservoir via vertical displacement of the moveable roller.   
     
     
         8 . The indicator of  claim 7 , wherein
 at least one of the platform and the base comprises a track accommodating the moveable roller, the track including at least one of a ramp or a step that forces the moveable roller to move vertically in response to the relative lateral motion between the platform and the base.   
     
     
         9 . The indicator of  claim 8 , wherein
 the pressure applied to the reservoir is operable to force a fluid contained in the reservoir through the seal and into communication with the timing strip.   
     
     
         10 . The indicator of  claim 8 , wherein
 the reservoir and the timing strip are included in a discrete package removable from at least one of the base and the platform.   
     
     
         11 . The indicator of  claim 10 , wherein
 the discrete package comprises an adhesive strip configured to at least temporarily attach the discrete package to at least one of the base and the platform.   
     
     
         12 . The indicator of  claim 2 , further comprising:
 a top cover
 wherein the platform is slideably mounted between the top cover and the base; 
 the tactile indicator comprises a post that is visible, and can be felt through a slot in the top cover; and 
 the visual indicator is secured to the top cover. 
   
     
     
         13 . The indicator of  claim 12 , wherein
 the tactile indicator comprises a plurality of graduations indicative of different tensions applied to the tourniquet tension indicator.   
     
     
         14 . A method of providing a tourniquet tension indicator comprising:
 applying a pressure sufficient to stop a blood flow to a limb using a tourniquet around the limb;   initiating a chemical action by causing a fluid to come into communication with a timing strip when the pressure sufficient to stop the blood flow to the limb is applied;   observing the timing strip to determine an elapsed time of the applying the pressure sufficient to stop the blood flow; and   reducing the pressure such that the blood flow returns to the limb once the elapsed time exceeds a predetermined length.   
     
     
         15 . The method of  claim 14 , wherein initiating a chemical action further comprises:
 crushing a reservoir containing the fluid such that the fluid comes into communication with the timing strip.   
     
     
         16 . The method of  claim 15 , wherein crushing the reservoir containing the fluid comprises:
 moving a platform laterally relative to a base until a moveable roller breaks a seal between the reservoir and the timing strip wherein
 the moveable roller is configured to move vertically in response to lateral relative motion between the platform and the base. 
   
     
     
         17 . The method of  claim 16 , wherein
 at least one of the platform and the base comprises a track accommodating the roller, the track comprising at least one of a ramp or a step that forces the roller to move vertically in response to the lateral relative motion between the platform and the base.   
     
     
         18 . A tourniquet tension indicator comprising:
 a tension indicator comprising:
 a base configured to attach to a strap; 
 a platform configured to move relative to the base when subjected to a lateral tension applied to the base and the platform; 
 a visual indicator configured to provide a variable visible indicator based on the lateral tension applied to the base and the platform; and 
 an initiator configured to apply a pressure to the visual indicator based on relative lateral motion of the platform to the base; and 
   the strap adapted to be secured around a limb.   
     
     
         19 . The indicator of  claim 18 , further comprising:
 a compressible member disposed substantially in-plane with the platform, wherein
 the compressible member is configured to resist movement of the platform relative to the base when lateral tension is applied to the base and the platform and the tourniquet strap is tightened around a limb; and 
   a top cover, wherein
 the platform is slideably mounted between the top cover and the base; 
 at least one of the top cover, the platform, and the base comprises a slot through which a tactile indicator may be viewed and felt; and 
 the tactile indicator is configured to move laterally in the slot as the platform moves relative to the base. 
   
     
     
         20 . The indicator of  claim 18 , wherein
 the visual indicator comprises a reservoir, a timing strip, and a seal between the reservoir and the timing strip; and   the initiator comprises a moveable roller that is configured to move vertically in response to relative lateral motion between the platform and the base, and to apply pressure to the reservoir via vertical displacement of the moveable roller.