A blood treatment apparatus (100) for extracorporeal blood treatment is disclosed. The apparatus comprises an arterial line (102) and a venous line (104) for connecting to a patient, wherein an arterial clamp (106) is arranged on the arterial line (102) for selectable clamping and unclamping of the arterial line (102) an arterial chamber (110) for connecting to the arterial line a venous chamber (112) for connecting to the venous line a blood pump (116) connected to the arterial chamber (110) and for providing blood via a blood treatment device (118) towards the venous chamber (112) an infusion liquid port (120) for connection of a infusion liquid source and a controller (114) arranged to control the apparatus. A method for controlling the apparatus and a computer program for the controller are also disclosed.
