The device has an oxygenator, a heat exchanger which together with the oxygenator forms an oxygenator heat exchanger structural unit having an inlet and an outlet. The inlet and outlet into the oxygenator heat exchanger unit has a blood flow cross-section of 80 mm2. A blood filter is coupled to the structural unit and has a blood flow cross-section which corresponds to the blood flow cross-section of the structural unit. The blood flow cross-sections are equal to 120 mm2.
