Patent attributes
A blood drawing system including a closeable first conduit through which drawn blood can flow; a first pressurizeable collection vessel for receiving blood therein; a hollow-shaft member; a second conduit leading from the first conduit to the first collection vessel; and a third conduit leading from the first conduit to the hollow shaft member connectable to a negative-pressure second collection vessel. Closing the first conduit allows blood transfer from the first vessel into the second vessel without exposure to or inclusion of any external devices to accomplish such transfer. Also included is an intravenous system with a conduit through which medicament liquid can be delivered and from which medicament liquid-free blood can be withdrawn. A first pressurizeable vessel first removes and conserves for reintroduction residual medicament liquid from the conduit, while thereafter a second negative-pressure vessel draws subsequent medicament liquid-free blood from the conduit.