1. A pressure activated valve for a vascular access catheter, comprising:a hub for introducing fluid to or removing fluid from the vascular access catheter, the hub comprising:
a housing having a proximal end and a distal end, the housing being comprised of:
a first portion and a second portion;
a lumen extending from the proximal end of the housing to the distal end of the housing, the lumen being substantially cylindrical and allowing for fluid to flow into and out of the vascular access catheter;
a membrane seat located within the lumen of the housing and adjacent the distal end of the housing;
a flow control membrane including a plurality of non-intersecting slits, and a seating portion located along a periphery of the flow control membrane, wherein the seating portion is configured to engage the membrane seat of the housing, situating the flow control membrane adjacent the distal end of the housing; and
a resilient annular base member comprising of a different thickness than the flow control membrane, the different thickness being thicker than the flow control membrane, the base member having an outer periphery that aligns with the seating portion of the flow control membrane and the membrane retention portion of the housing, the resilient annular base member being stacked either on a top surface of the seating portion of the flow control membrane or on a bottom surface of the flow control membrane such that the resilient annular base member and membrane seat contact opposite and equal portions of a periphery of the flow control membrane, the resilient annular base member being a separate component from the flow control membrane,
wherein the plurality of non-intersecting slits open when subjected to a fluid pressure of at least a predetermined threshold level.