Reusable fluid pumping device

A pump assembly for use with an IV set, the pump assembly comprising:

• a rotatable crank with an exterior profile that defines a plurality of lobes;
• a biasing member coupled to the crank and configured to rotate the crank;
• a piston rod comprising a first follower and a second follower spaced apart from the first follower, wherein the first follower contacts the exterior profile to selectively advance the piston rod, the second follower contacts the exterior profile to selectively retract the piston rod, and rotation of the crank in a single rotation direction relative to the piston rod causes the piston rod to cyclically reciprocate relative to the crank;
• and
• a diaphragm assembly comprising:
• a housing;
• and
• a resilient diaphragm member coupled to the housing and cooperatively defining a volume in fluid communication with the IV set, wherein the diaphragm member is movable between an extended position configured to increase the volume and to draw in fluid from the IV set and a contracted position configured to decrease the volume and to expel fluid into the IV set, and the diaphragm member is coupled to the piston rod to reciprocate the diaphragm member between the extended position and the contracted position.