Fluid collection device with captured retractable needle

A medical device, comprising:

• a hollow housing having an aperture in a wall of the housing, the aperture forming a rim;
• a needle having a sharpened tip operable between an extended position in which the sharpened tip is exposed for use and a retracted position in which the needle is shielded against inadvertent contact;
• a biasing element biasing the needle toward the retracted position;
• a needle hub having a cylindrical body axially displaceable within the housing between a forward position and a rearward position,
• the needle hub having a central bore for receiving the needle, wherein the needle is fixedly attached to the needle hub,
• the needle hub further comprising a connector adjacent the rearward end of the hub configured for providing a fluid tight connection between a fluid line and the needle;
• a needle retainer releasably retaining the needle in the projecting position against the bias of the biasing element, comprising:
• a radially deformable arm attached to the needle hub and projecting radially outwardly from the needle hub;
• and
• an actuator disposed at the end of the arm releasably engaging the rim of the aperture and having a surface directly manually operable from outside the housing, wherein depressing the actuator releases the needle whereupon the biasing element displaces the needle hub into the rearward position;
• a locking flange projecting radially outwardly from the needle hub, axially spaced from the actuator of the needle retainer;
• a locking latch projecting radially inwardly from the wall of the housing, wherein the latch is configured to engage the locking flange to impede rearward axial movement of the needle hub when the needle is displaced into the rearward position;
• a forward stop operable to impede forward axial movement of the needle hub after the needle hub is displaced into the rearward position, wherein the forward stop is deformed radially as the needle hub is displaced from the forward position to the rearward position;
• and
• a flexible cannula fixedly attached to the forward end of the housing, sheathing a portion of the needle when the needle is in the projecting position, wherein when the needle is displaced into the retracted position, the needle is in fluid communication with the cannula;
• wherein the biasing element has a biasing force between an upper limit and a lower limit, the lower limit being defined by the amount of axial force required to effectuate radial displacement of the forward stop during retraction and the upper limit being defined by the amount of axial force required to overcome the engagement between the locking latch and the locking flange, and the bias of the biasing element.