A system (5, 405) for infusing medication into a subject is provided. The system (5, 405) includes an injection system (50, 450) for controlling fluid flow from a fluid reservoir to a needle. A sensor (20) detects a characteristic indicative of fluid pressure in the needle. The injection system (50, 450) controls the flow of fluid to the needle in response to the characteristic detected by the sensor (20), which continuously detects the characteristic as the needle is inserted into the subject. The system may include a light assembly (100) connected with the injection system. The light assembly (100) may provide a continuously variable signal indicative of the fluid pressure in the needle. The system (5, 405) may further provide a mechanism that provides cues to the operator to insert the needle at a particular rate. The system may further include a conductive element (334) for providing electric nerve stimulation.