Interface device between a hemodialysis machine and venous and arterial tubes, this interface device comprising: a first port adapted to be connected to an output port of the hemodialysis machine； a venous port to inject blood into the venous tube； said interface device comprises: a second port adapted to be connected to an input port of the hemodialysis machine； an arterial port for receiving blood from the patient from the arterial tube, the interface device being further adapted to selectively allow or prohibit the passage of blood between the first and second ports and the venous and arterial ports respectively.
