Cannula with introducer, needle protecting guard and blood collecting system

Abstract

A cannula introducing device comprises an elongate body ( 10 ) having a needle ( 12 ) projecting from a front end, an operating element ( 24 ) for displacement longitudinally of the body ( 10 ), a plunger ( 16 ) disposed at the front end of the body ( 10 ), and a coupling means ( 18 ), such as a flexible wire, coupling the operating element ( 24 ) and the plunger ( 16 ), arranged so that retraction of the operating element ( 24 ) serves to advance the plunger ( 16 ) over the needle ( 12 ) and so advance the cannula ( 30 ) which is disposed over the needle.

1 . A cannula introducing device which comprises an elongate body having a needle projecting from one end thereof, an operating element mounted to said body for displacement longitudinally thereof, a plunger disposed at said one end of said body, and means coupling said operating element and said plunger and arranged so that displacement of said operating element away from said one end of said body causes displacement of said coupling means to advance said plunger along said needle. 
   
   
       2 . A device as claimed in  claim 1 , arranged for said plunger to be displaceable, by displacement of said operating element, far enough to cover the tip of said needle. 
   
   
       3 . A device as claimed in  claim 1 , arranged for said plunger to be advanced an initial distance by said displacement of said operating element, the device further comprising a spring serving to advance said plunger through a further distance. 
   
   
       4 . A device as claimed in any preceding claim, including means for preventing said plunger being retracted after having been advanced along said needle. 
   
   
       5 . A device as claimed in any preceding claim, in which said coupling means comprises an elongate flexible element which extends along a guideway of said body, between said operating element and said plunger, and arranged to be displaced longitudinally of itself as said operating element is displaced. 
   
   
       6 . A device as claimed in  claim 5 , in which said flexible element is arranged to push said plunger forwardly along said needle. 
   
   
       7 . A device as claimed in  claim 5 , in which said flexible element is arranged to pull said plunger forwardly along said needle. 
   
   
       8 . A device as claimed in  claim 6 , in which said guideway comprises a groove or channel formed in said body, said operating element being engaged into said groove or channel for sliding movement along it. 
   
   
       9 . A device as claimed in  claim 8 , in which said operating element comprises a member which projects outwardly from said groove or channel, for the user to engage manually. 
   
   
       10 . A device as claimed in any one of  claims 5 ,  6 ,  8  or  9 , in which said guideway further comprises a passage having a first portion which extends from the rear end of said groove or channel and curves round to a second portion which extends forwardly to said one end of said body. 
   
   
       11 . A device as claimed in  claim 10 , in which said second portion of said guideway is disposed in or adjacent a surface of said body remote from or opposite a surface in which said guide groove or channel is formed. 
   
   
       12 . A device as claimed in any one of  claims 5  to  11 , in which said coupling means comprises a wire. 
   
   
       13 . A device as claimed in  claim 12 , in which said wire is of a flat cross-sectional profile. 
   
   
       14 . A device as claimed in any preceding claim, in which said body is arranged to receive a fluid-collecting container for receiving blood or other fluid through said needle. 
   
   
       15 . A device as claimed in  claim 14 , in which said body includes an internal chamber to receive blood or other fluid through said needle, said chamber being provided with a plunger which is displaced upon retraction of said operating element, or of a secondary operating element, for a piercing needle of said plunger to pierce a membrane closing the end of said fluid-collecting container. 
   
   
       16 . A device as claimed in  claim 14  or  15 , in which said body is formed with an elongate compartment for the longitudinal insertion of a said container of tubular form, said compartment being provided with a longitudinal member for piercing said membrane of said container and to bear on and displace an internal piston of said container, as said container is inserted into said compartment. 
   
   
       17 . A device as claimed in any one of  claims 14  to  16 , in combination with a said fluid-collecting container inserted into or for insertion into said body. 
   
   
       18 . A device as claimed in any preceding claim, in combination with a cannula received over said needle. 
   
   
       19 . A device for collecting a sample of blood or other fluid, the device comprising an elongate body having a needle projecting from one end thereof, the body having an interior compartment for receiving a fluid-collecting container and having a plunger disposed therein, the device further comprising an operating element arranged for displacement longitudinally of said body away from said one end thereof, in order to displace said plunger and for a piercing needle provided on said plunger to pierce a membrane which closes said container. 
   
   
       20 . A device as claimed in  claim 19 , in combination with a fluid collecting container received or for receiving within said body. 
   
   
       21 . A container for collecting a sample of blood or other fluid, the container being of tubular form and having one end closed by a piercable membrane and having an internal piston positioned adjacent said membrane.