The invention relates to a medical device (12) comprising an electrical measurement circuit (16), in which are connected at least two variable-impedance sensors (22), the impedance of which varies according to a detected physical quantity, an electrical power source (18) for supplying power to the electrical measurement circuit (16), an antenna (18) for emitting an electromagnetic field according to the impedance of the electrical measurement circuit (16), each of the sensors (22) being associated with a switch (24) for interrupting the current supply of the sensor (22) in said measurement circuit (16), the medical device (12) additionally comprising a system (26) for controlling the switches (24) in order to successively control the opening or the closing of the switches (24), according to determined configurations. The medical device (12) may in particular be applied to the human body or implanted within the human body.