Patent ID: 6302860
Filing Date: 2001-10-16
Classification: A61M

Abstract:
A heart-lung machine, comprising:a) a venous return line receiving venous blood from a patient, said venous return line being under negative pressure;b) an arterial supply line supplying arterial blood to the patient;c) a negative pressure air filter connected directly to said venous return line so as to draw the patient's venous blood through said negative pressure air filter;d) a blood pump and a blood oxygenator connected between said negative pressure air filter and said arterial supply line, said blood pump being arranged to pump blood directly from said negative pressure air filter toward said arterial supply line; ande) said negative pressure air filter including:i) a blood intake;ii) a bubble trap arranged to trap air bubbles present in the patient's venous blood;iii) an air chamber positioned above said blood intake and arranged to receive air bubbles trapped by said bubble trap;iv) an air sensor arranged to sense the presence of air in said air chamber; andv) a vacuum applied to said air chamber, said vacuum being applied when, and only when, said sensor senses the presence of air In said chambers so as to maintain said filter filled with blood but prevent blood from being aspirated into a purge line.