A device for drawing fluid from a lumen, and particularly blood from a blood vessel, is disclosed. The device may provide indication of the entry of an intravenous cannula into the lumen. The device may include a central body having an outer wall and an inner fluid passage. The device may include a luer-type adapter to permit the attachment of an I.V. infusion set of various lengths ("butterfly needle") and or any luer-type fitting attached to an existing device. The outer wall of the central body may be transparent or translucent to permit the detection of fluid within the inner fluid passage. A front cannula may extend from one end of the central body and a rear cannula may extend from the other end of the central body. Both the front and rear cannulae may communicate with the inner fluid passage. An air-permeable flexible sleeve may surround at least a tip portion of the rear cannula. The air-permeable flexible sleeve may act as a venting member positioned between the rear cannula and the ambient. The venting member may permit the passage of air through it, but be substantially impermeable to liquids, such as blood.