Patent ID: 7794419

Claim:
A blood treatment machine comprising: an extracorporeal circuit having at least a blood treatment unit, at least an access branch extending between a blood removal zone of a patient and the treatment unit, at least a return branch extending between the treatment unit and a blood return zone to the patient, at least a vascular access organ interpositioned between said branches and a patient's vascular system, and at least a pump associated to the extracorporeal circuit, and an apparatus for controlling blood flow in the extracorporeal circuit, the apparatus comprising: at least a user interface for enabling a setting of a desired value of blood flow (q bREAL ) through the access branch and in order to allow entry of at least a datum relating to the vascular access; a memory storing a plurality of mathematical relations, each of said mathematical relations having a respective mathematical expression which is a function of the vascular access organ to be used and mathematically linking the blood flow through the access branch with an angular velocity of the pump; a control unit, connected to the user interface and the pump, which control unit is programmed for performing a process as follows: identifying the vascular access; selecting, from among the plurality of mathematical relations present in the memory, the mathematical relation which corresponds to the identified vascular access; calculating, using the mathematical relation loaded from said memory, at least one from following values: a value at which the angular velocity of the pump can be set as a function of a set value for a desired flow (q bREAL ), and a theoretical value of the arterial pressure in the arterial branch upstream of the pump, as a mathematical function of the set value for the desired flow (q bREAL ).