Needle assembly having single handedly activated shield

A shielded needle assembly comprising:

• an elongate needle having a proximal end, a distal end and a passageway therethrough defining an axis;
• a needle hub having a proximal end, a distal end and an outside surface, said needle hub having an axial opening therethrough to receive and hold said needle with said distal end of said needle projecting distally axially therefrom, said proximal end of said needle hub further including means for releasably mounting said needle hub on a fluid handling device;
• an elongate shield having a proximal end, a distal end, a sidewall having an elongate opening from said distal end to said proximal end, wherein at least a section of said shield is substantially cylindrical with an exterior surface having an outwardly extending circumferential shoulder, said shoulder being located and sized so that when said latch means is disposed on said shield, said shield being operable between an open position, wherein said needle is exposed for use by passage through said elongate opening, a closed position, wherein said shield substantially obstructs access to said needle, and a latched position, wherein said shield is closed, said elongate opening is substantially obstructed and said shield is substantially prevented from inadvertent movement to said open position;
• latch means including a visual indication of said elongate opening being substantially obstructed, said latch means comprising an elongate hollow cylinder with an outwardly extending tab and an inside surface, said cylinder having a open proximal end, a open distal end and a sidewall with an elongate slot from said proximal end to said distal end, therethrough, said hollow cylinder further including a circumferential groove in said inside surface, said hollow cylinder being disposed coaxially about said cylindrical section of said shield so that said shoulder engages said circumferential groove thereby retaining said latch means on said shield and allowing a annular rotation of said latch means with respect said cylindrical section;
• and
• hinge means including a mount for retaining said shield onto said needle hub, said mount having an axial passage therethrough sized and shaped to receive at least a portion of said needle hub, said shield movable between said open position and said closed position over said needle by an off-axis pivotal movement about said hinge means, and said shield being latched and unlatched in said closed position by a rotational movement of said latch means with respect to said shield, and wherein said at least a portion of said cylindrical section of said shield has a contrasting color to a color of said latch means so that when said shield is latched with said elongate opening being substantially obstructed, said contrasting color is visible through said elongate slot in said latch means thereby providing said visual indication that said shield is substantially prevented from inadvertent off-axis pivotal movement to expose said needle.