#$%^&*AU2018236852A120181018.pdf#####ABSTRACT A catheter hub assembly includes a body. A pressure sensor is disposed within the body to sense pressure within a catheter and communicating with the body The body has a chamber formed therein having a predetermined volume. A stopper assembly, slideably moves to engage the body forming a gastight seal within the chamber for pushing a column of gas ahead of the stopper assembly as the stopper assembly moves from a first position to a second position. AM 30181252.1
