Patent ID: 8394047
Filing Date: 2013-03-12
Classification: A61M

Abstract:
1. Extracorporeal blood treatment apparatus comprising: a membrane device having a first chamber, a second chamber and a semipermeable membrane separating said first chamber from said second chamber; a single needle extracorporeal blood circuit having a three way junction connecting a patient line, a first line and a second line, said patient line being connectable to a patient vascular access, said first line being connected to an inlet of said first chamber, said second line being connected to an outlet of said first chamber, said single needle extracorporeal blood circuit being provided with an expansion chamber; a first pump and a second pump configured to circulate a blood flow in said single needle extracorporeal blood circuit; an ultrafiltration device operatively connected to said second chamber; a control unit configured to control said first and second pumps to circulate a blood flow in said single needle extracorporeal blood circuit and to control said ultrafiltration device to perform a pure ultrafiltration of ultrafiltrate from said blood flow through said semipermeable membrane, said controller configured to control said first and second pumps so as to alternate a withdrawal phase in which blood is withdrawn from said patient vascular access through said patient line and a return phase in which blood is returned to said patient vascular access through said patient line, wherein said controller is configured to operate both said first and second pumps during said withdrawal phase so as to recirculate a fraction of blood flow from said second line to said first line through said three way junction and said controller is further configured to control said first pump at a flow rate higher than a flow rate of said second pump during said withdrawal phase and less than a flow rate of said second pump during said return phase, and wherein said controller is configured to operate said ultrafiltration device so as to perform a pure ultrafiltration treatment during said recirculation.