A minor alteration in the Unger blood transfusion apparatus now in general use makes possible a radical change in the method of operation, having important advantages. This consists merely in discarding the rubber tubing and adapter that are attached to the nipple at the saline opening. In place of this nipple,÷ a female adapter made from the hilt of a record cannula is brazed strongly to the machine in line with the port C, as shown in the accompanying illustration. This new attachment receives the tip of a record syringe.
The change from the Unger method of operation is as follows: No saline solution is employed during the transfusion, and whole blood only is used. A record syringe, A, operates similarly to the original record syringe, B, of the Unger method and works in opposite phase to it. While A is filled from the donor,B discharges into the recipient, and the two operations are simultaneous.