Device and procedure for collecting a succession of intravenous blood samples

Claim 1

In a blood sample collection system for use with an intravenous needle, the combination comprising a pre-evacuated vial having an extensive rubber cap, a carrier in the form of a large cylindrical cup defining a main chamber and a small cylindrical cup defining a mid-chamber, the cups having their mouths facing in opposite directions and being integral with one another base-to-base to form a thin common barrier between them and with their axes parallel and offset from one another to a degree that adjacent portions of the sidewalls thereof are substantially flush, the cups communicating via a clearance opening through the barrier and which is axially aligned with respect to the axis of the small cup, a readily-penetrated soft rubber disc at the mouth of the small cup, an end fitting secured to the mouth of the small cup adjacent the rubber disc for coupling to the intravenous needle and having an axial passageway formed therein, the end fitting being formed of transparent plastic and the axial passageway being relieved to form an antechamber immediately adjacent the rubber disc for reception of a trace of blood under venous pressure as a preliminary visual telltale that the lumen of the vein has been penetrated, a piston fitted for sliding movement endwise in the mid-chamber between limit positions, the piston having an auxiliary double-ended needle axially mounted therein and projecting from the ends thereof one end of which extends through the clearance opening in the common barrier and the other end of which is positioned for penetration of the soft rubber disc, the large cylindrical cup slideably receiving said vial with the rubber cap positioned for penetration by the one end of the auxiliary needle so that when the vial is pressed in, cap-first, the auxiliary needle first penetrates the soft rubber disc to establish communication with the intravenous needle and then penetrates the rubber cap on the vial in a random eccentric position to establish communication between the vial and the intravenous needle for the drawing of a sample of blood into the vial, and with the auxiliary needle being drawn from the rubber disc and then from the cap for resealing of the same when the vial is subsequently removed.