Download online extravascular system

A medical device, comprising: a closed extravascular system (10) including a catheter assembly (14) is connected to an adapter (18) by an extension pipe (16), the system (10) defines a fluid path (28) extending through the catheter assembly (14), the extension tube (16) and adapter (18); wherein the adapter (18) comprises at least one vascular access device (24, 62, 100) forming an opening through the adapter (18) through which access to the fluid path (28), adapter (18) also includes a gas discharge (30) forming an opening through the adapter (18) for discharging the gas contained within the fluid path (28) when blood flows from a patient fluid path (28), the opening formed by the element gas discharge (30) is separated from the opening formed by each of at least one vascular access device (24, 62, 100) such that the gas can downloaded from the fluid path (28) without passing through the opening formed by the at least one vascular access device (24, 62, 100).