Abstract: A cardiotomy reservoir which employs an inner wall structure which defines a central receiving chamber. The receiving chamber wall is tapered inwardly to provide a smooth blood flow along an arcuate imperforate portion which extends from the top to the bottom thereof into the blood receiving chamber. Apertures in another arcuate portion of the wall member allow fluid communication between the receiving chamber and the blood treatment element. Blood flow directing means direct blood entering the inlet port of the device downward toward the bottom of the receiving chamber along the imperforate portion of the inner wall so that the inflowing blood does not splash and has low turbulence.

Abstract: A yoke shaped collapsible blood reservoir having first and second yoke legs joined by a yoke midsection. A filter element is positioned in the yoke midsection and across the blood flow path between an inlet at the base of the first yoke leg and a blood outlet at the base of the second yoke leg. An angular blood inlet and a gradual increase in cross-sectional area from the blood inlet to the yoke midsection decreases turbulence and assists in bubble separation.