A medical apparatus comprises a machine for treatment of fluids provided with means (3) for treating a patient's blood which exhibit a control unit (4) for sending command signals and receiving information relating to the treatment under way on the patient. A remote unit (7) is included which enable the remote unit (7) to selectively take control of a predetermined number of functions of the medical machine. The control unit (4) of the medical machine is predisposed to selectively inhibit the remote control means (10) from taking or maintaining control of the functions of the medical machine in consequence of the operating configuration of the machine.