Abstract: A removable head is provided for connection to an immovable percutaneous passage device giving access to a fluid circuit in a living organism, a fluid distribution housing and a system comprising this connection head and this fluid distribution housing.Through the connection head of the invention a percutaneous passage, implanted in the blood network of a living organism, can be connected to an apparatus for treating the blood. It comprises a base, screwable on the percutaneous passage, forming a guide cylinder, for a tubular body through which are formed at least two channels. Means for actuating the head impart to the tubular body a translational movement which establishes in turn a direct flow between the channels then places them independently of each other in contact with the organism. The head of the invention further comprises safety devices and is motorizable.