Medical valve with positive flow characteristics

Abstract

A medical valve device for use in selectively establishing a fluid flow between first and second medical implements is disclosed. The valve has a body defining a passage from a first port to a second port. The valve defines a first fluid volume when both medical implements are connected thereto, and a second, smaller volume when one of the implements is disconnected, thereby causing a positive flow of fluid from the valve to the second medical implement when the first implement is disconnected.

What is claimed is:  
     
         1 . A method of effecting a positive flow of fluid through a first medical implement automatically upon disconnection of a second medical implement from a valve having a housing with an element therein for controlling the flow of fluid through said housing, said valve defining a fluid volume within said housing and said valve in communication with said first medical implement, comprising the steps of: 
 disconnecting said second medical implement from said valve;    moving at least a portion of said element to a position in which fluid flow through said valve to said second medical implement is prevented;    decreasing the fluid volume within said valve; and    forcing fluid from said housing towards said first medical implement.    
     
     
         2 . The method in accordance with    claim 1   , wherein said element comprises a resilient seal positioned in said housing, said seal having a passage therethrough and wherein said moving step comprises allowing said seal to expand to a position in which said passage therethrough is occluded.  
     
     
         3 . The method in accordance with    claim 1   , wherein a piston member is movably positioned within said housing of said valve and said decreasing step comprises moving said piston member.  
     
     
         4 . The method in accordance with    claim 3   , wherein said step of disconnecting comprises removing said first medical implement from a first end of said valve, and wherein said decreasing step comprises moving said piston towards said first end of said valve.  
     
     
         5 . The method in accordance with    claim 1   , wherein a member is positioned within said housing, said member arranged to increase said fluid volume in said housing when said first medical implement is connected to said valve, and wherein said step of decreasing the volume within said housing comprises the step of allowing said member to expand in volume.  
     
     
         6 . The method in accordance with    claim 1   , wherein a member is positioned within said housing and cooperates with said housing to form a chamber, and said step of decreasing the volume within said housing comprises the step of enlarging the volume of said chamber.  
     
     
         7 . The method in accordance with    claim 1   , wherein said element comprises a seal, and further including a piston movably positioned within said valve, said piston cooperating with said seal and housing to define said fluid volume, and wherein said step of decreasing the fluid volume comprises the step of moving said piston towards said seal.