Blood filter

Abstract

Abstract A blood filter (10) such as may be used in a cardiopulmonary bypass system includes a housing (27) having upper and lower chambers (49, 36) with a cylindrical filter element (26) disposed in the lower chamber (36). The inlet (28) to the housing is in the upper chamber (49), which is upstream of the lower chamber (36), and the outlet (29) is through the lower chamber (36) and communicates with the interior of the filter element (26). Thus, blood enters the upper chamber (49) and flows to the lower chamber (36) where it passes through the filter element (26) from the outer side to the interior to remove microemboli such as gas bubbles, fat emboli and agglomerates, the filtered blood exiting through the outlet (29). In order to remove a substantial amount of the gas in the blood, and particularly gross bubbles, upstream of the filter element (26), the upper chamber (49) is cylindrical and the inlet (28) directs the blood tangentially to flow around the periphery of the chamber (49). An annular baffle (53) extending around a major portion of the chamber (49) maintains the peripheral flow which produces a centrifugal action causing the blood to flow at the wall of the chamber (49) and the gas to separate and move to the central portion where it is vented through a hydrophobic membrane (51) covering the central portion (49a) of the top wall of the chamber (49). Blood from the periphery of the upper chamber (49) flows down to the lower chamber (36) through a sponge ring (69) which removes additional gas bubbles.

Inventors

• 👤 David John Rosenberg
• 👤 Vlado Ivan Matkovich

Bibliographic Details