Fingertip conforming fluid expression cap

Abstract

A bodily fluid sampling device includes an incision forming device to form an incision in a finger and an expression cap. The expression cap has an opening through which the incision forming device forms an incision and an expression surface to express fluid from the incision. The expression surface has at least two opposing compression surfaces with a negative sigmoidal shape to enhance expression of body fluid from the incision. The expression cap defines a relief notch between the compression surfaces, and the relief notch is sized to receive the finger, or some other body part, to permit the compression surfaces to first contact the finger when the expression surface is pressed against the finger.

1 . A bodily fluid sampling device, comprising: 
 an incision forming device to form an incision in a finger; and    an expression cap defining an opening through which the incision forming device forms an incision, the expression cap having an expression surface to express fluid from the incision, the expression surface having at least two opposing compression surfaces with a negative sigmoidal shape to enhance expression of body fluid from the incision, the expression cap defining a relief notch between the compression surfaces, the relief notch being sized to receive the finger to permit the compression surfaces to first contact the finger when the expression surface is pressed against the finger.    
   
   
       2 . The sampling device of  claim 1 , wherein: 
 the expression cap includes a support portion and an expression portion detachably coupled to the support portion, wherein the expression portion is detachable from the support portion to allow cleaning of the expression portion.    
   
   
       3 . The sampling device of  claim 1 , further comprising a testing device disposed in the expression cap for analyzing the fluid from the incision.  
   
   
       4 . The sampling device of  claim 1 , wherein the expression surface is textured to enhance expression of fluid from the incision.  
   
   
       5 . The sampling device of  claim 4 , wherein the expression surface defines a plurality of ridges.  
   
   
       6 . The sampling device of  claim 1 , wherein the relief notch extends on opposite sides of the opening.  
   
   
       7 . The sampling device of  claim 1 , further comprising a device body coupled to the expression cap.  
   
   
       8 . The sampling device of  claim 7 , wherein the expression cap is removable from the device body.  
   
   
       9 . A bodily fluid sampling device, comprising: 
 means for forming an incision in a body part; and    an expression cap defining an opening through which the means for forming the incision forms the incision, the expression cap having an expression surface, the expression surface defining a relief notch, wherein the expression surface is shaped to apply a generally even force against the body part when expressing body fluid from the incision.    
   
   
       10 . The sampling device of  claim 9 , wherein the expression surface has a negative sigmoid shape.  
   
   
       11 . The sampling device of  claim 9 , wherein the expression surface has a saddle shape.  
   
   
       12 . The sampling device of  claim 9 , wherein the relief notch extends across the opening.  
   
   
       13 . The sampling device of  claim 9 , wherein the expression cap has a generally cylindrical shape.  
   
   
       14 . The sampling device of  claim 9 , wherein an area of contact between the expression surface and the body part has a surface area between about 0.2 to 0.6 square inches.  
   
   
       15 . A method, comprising: 
 providing a sampling device that has an expression surface with at least two opposing compression surfaces that have a negative sigmoidal shape and a relief notch defined between the compression surfaces that is shaped to generally conform to a body part;    placing the expression surface against the body part with at least a portion of the body part received in the relief notch;    forming an incision in the body part with the sampling device; and    expressing body fluid from the incision by exerting pressure between the body part and the expression surface.    
   
   
       16 . The method of  claim 15 , wherein the expression surface has a negative sigmoid shape.  
   
   
       17 . The method of  claim 15 , further comprising analyzing the body fluid with the sampling device.  
   
   
       18 . The method of  claim 15 , further comprising keeping the sampling device in place against the body part during said forming and said expressing.  
   
   
       19 . The method of  claim 15 , wherein said placing the expression surface against the body part occurs before said expressing the body fluid.  
   
   
       20 . The method of  claim 15 , wherein said expressing includes pressing the body part against the expression surface.  
   
   
       21 . The method of  claim 15 , wherein said expressing includes pressing the expression surface against the body part.  
   
   
       22 . The method of  claim 15 , wherein: 
 the sampling device includes an incision forming device;    the expression surface defines an opening; and    said forming the incision includes forming the incision through the opening with the incision forming device.