A medical pump for delivering fluid to a patient, comprising: a pump cavity which is surrounded by a rigid wall and which includes a diaphragm opening; a diaphragm disposed over and sealed to the diaphragm opening of the pump cavity; a pump chamber defined by an inside surface of the rigid wall of the pump cavity and an inside surface of the diaphragm which disposed over and sealed to the pump cavity; a pressure actuator including a piston with a distal end that is operatively coupled to the diaphragm; an outlet conduit which is in fluid communication with the pump chamber; an outlet port which is in fluid communication with the outlet conduit; a flow control valve which is operatively coupled to the outlet conduit between the pump chamber and the outlet port, characterized by the flow control valve comprising: a rigid base having a top surface with an upstream orifice and a downstream orifice, and a distensible membrane secured to the top surface of the rigid base in sealed relation relative to the upstream orifice and the downstream orifice so as to be in approximation with the top surface of the rigid base forming a sealed distensible channel between the upstream and downstream orifices (54, 56), the distensible channel being normally closed and being created by joining the distensible membrane film to the top surface of the rigid base. a pump cavity which is surrounded by a rigid wall and which includes a diaphragm opening; a diaphragm disposed over and sealed to the diaphragm opening of the pump cavity; a pump chamber defined by an inside surface of the rigid wall of the pump cavity and an inside surface of the diaphragm which disposed over and sealed to the pump cavity; a pressure actuator including a piston with a distal end that is operatively coupled to the diaphragm; an outlet conduit which is in fluid communication with the pump chamber; an outlet port which is in fluid communication with the outlet conduit; a flow control valve which is operatively coupled to the outlet conduit between the pump chamber and the outlet port, characterized by the flow control valve comprising: a rigid base having a top surface with an upstream orifice and a downstream orifice, and a distensible membrane secured to the top surface of the rigid base in sealed relation relative to the upstream orifice and the downstream orifice so as to be in approximation with the top surface of the rigid base forming a sealed distensible channel between the upstream and downstream orifices (54, 56), the distensible channel being normally closed and being created by joining the distensible membrane film to the top surface of the rigid base. a rigid base having a top surface with an upstream orifice and a downstream orifice, and a distensible membrane secured to the top surface of the rigid base in sealed relation relative to the upstream orifice and the downstream orifice so as to be in approximation with the top surface of the rigid base forming a sealed distensible channel between the upstream and downstream orifices (54, 56), the distensible channel being normally closed and being created by joining the distensible membrane film to the top surface of the rigid base.