A system for controlling fluid flow in a catheter assembly, comprising: an intravenous catheter assembly having a catheter adapter (14) comprising an inner lumen； an integrated septum (50) and septum actuator (80) disposed within a portion of the inner lumen, the integrated septum and septum actuator comprises a base having a fluid pathway and an extension arm extending outwardly from the base, the extension arm being coupled to a septum being deformable from a relaxed position to a stressed position, wherein a pathway around an outer surface of the septum is closed when the septum is in the relaxed position, and the pathway around the outer surface of the septum is open when the septum is in the stressed position.
