It is disclosed a needle (1) for a syringe, including a tip (2) at one end (3) of the needle, adapted to penetrate a body tissue during usage of the syringe, and a hub (4) at the other end (5) of the needle, to attach the needle to the syringe. A pressure sensor (6) is in the needle； means (7) are provided to transmit outside the needle a pressure value sensed by the pressure sensor (6) in the needle.
