A system (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000) for extracorporeal blood treatment, wherein the system (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000) comprises: - a first inlet for introducing a bloodstream to be treated into the system (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000), - at least one first blood treatment apparatus (A, PT), - one second blood treatment apparatus, - one third blood treatment apparatus, and - a first outlet for discharging a treated bloodstream from the system (100, 200, 300, 400, 500, 600,700, 800, 900, 1000), wherein the first blood treatment apparatus (A, PT) is or comprises an adsorber apparatus for removing at least one exogenous and/or at least one endogenous pathogen and/or a plasma separator apparatus for separating blood plasma from the other blood components, wherein the second blood treatment apparatus is designed as a dialysis apparatus, in particular as a dialysis apparatus for renal replacement therapy, and wherein the third blood treatment apparatus is designed as a gas exchange apparatus, in particular as a gas exchange apparatus for at least partially removing CO2 from a stream of blood flowing through the gas exchange apparatus and/or for supplying a gas or gas mixture into a stream of blood flowing through the gas exchange apparatus, and wherein the three blood treatment apparatus (A and/or PT, D, G) are sequentially connected in series in a functional state of system (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000) application between the first inlet and the first outlet of the system relative to a direction of blood flow of a bloodstream to be treated and can be consecutively perfused extracorporeally by a bloodstream to be treated. - a first inlet for introducing a bloodstream to be treated into the system (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000), - at least one first blood treatment apparatus (A, PT), - one second blood treatment apparatus, - one third blood treatment apparatus, and - a first outlet for discharging a treated bloodstream from the system (100, 200, 300, 400, 500, 600,700, 800, 900, 1000), wherein the first blood treatment apparatus (A, PT) is or comprises an adsorber apparatus for removing at least one exogenous and/or at least one endogenous pathogen and/or a plasma separator apparatus for separating blood plasma from the other blood components, wherein the second blood treatment apparatus is designed as a dialysis apparatus, in particular as a dialysis apparatus for renal replacement therapy, and wherein the third blood treatment apparatus is designed as a gas exchange apparatus, in particular as a gas exchange apparatus for at least partially removing CO2 from a stream of blood flowing through the gas exchange apparatus and/or for supplying a gas or gas mixture into a stream of blood flowing through the gas exchange apparatus, and wherein the three blood treatment apparatus (A and/or PT, D, G) are sequentially connected in series in a functional state of system (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000) application between the first inlet and the first outlet of the system relative to a direction of blood flow of a bloodstream to be treated and can be consecutively perfused extracorporeally by a bloodstream to be treated.