Patent ID: 8025633

Claim:
An arrangement for extracorporeal circulation of a blood related fluid in a circuit, the circuit comprising a bloodline and at least one component for circulation of the blood related fluid having an upstream inlet to the component, wherein the circuit comprises a flow expansion, the flow expansion comprising a first part having a first flow diameter d 1 and a first length extension L 1 and a second part downstream the first part having a second flow diameter d 2 and a second length extension L 2 where d 2 /d 1 ≧1.5 and L 2 /L 1 ≧ is 0.5 and wherein the second flow diameter d 2 is a maximum diameter of a flow passage in the second part and the diameter of the flow passage in the second part gradually expands from d 1 to d 2 along L 2 , and further wherein the flow passage in the second part includes a ledge at which the diameter d 2 is abruptly changed to a smaller flow diameter, said ledge disposed upstream of the inlet of the component.