Patent ID: 7922683

Claim:
An extracorporeal circulator comprising: a venous line for receiving blood from a patient; a blood pump for drawing the blood into the venous line; an artificial lung that performs gas exchange of the blood; an arterial line for returning the blood that has passed through the artificial lung to the patient; a bubble removing unit that removes bubbles mixed in the blood and including a detection mechanism for detecting a state of bubble presence in the bubble removal unit; blood-feed control means for controlling an amount of blood fed to the bubble removing unit; a closable bypass line for bypassing the blood discharged from the blood pump and returning the blood to the blood pump; and a by-pass opening and closing mechanism operably connected to the bubble detection mechanism and the blood-feed control means for opening and closing the by-pass line in response to a detection result received from the detection mechanism; wherein the bubble removing unit comprises: a circulation-flow forming chamber including an inner space having a substantially circular cross section; an inlet disposed substantially tangential to an inner periphery of the circulation-flow forming chamber, for introducing the blood into the circulation-flow forming chamber so that the blood forms a circulation flow in the circulation-flow forming chamber; an outlet disposed at a lower part of the circulation-flow forming chamber; and a bubble reservoir disposed on the circulation-flow forming chamber, for temporarily storing the bubbles rising from the circulation-flow forming chamber; a first communicating section communicating a vicinity of a top of the circulation-flow forming chamber with the bubble reservoir to allow the bubbles rising from the circulation-flow forming chamber to pass through the first communicating section and into the bubble reservoir; and a second communicating section for communicating the vicinity of a peripheral wall of the circulation-flow forming chamber with the bubble reservoir, wherein the bubbles rising from the circulation-flow forming chamber flow into the bubble reservoir through the first communicating section and the blood in the bubble reservoir is returned to the circulation-flow forming chamber through the second communicating section.