The invention provides improved devices and apparatuses and related methods for sensing differences in pressure or other parameters in the environment of the body of a patient during passage of the device through one or more tissues. In one aspect, the devices and apparatuses of the invention are configured to sense differences in the environment of the body of the patient as the device passes through tissue adjacent to the epidural space to tissue of the epidural space. In one aspect, a dual cannula device comprising one or more sensors connected to a signaling component is provided for sensing passage into of the device into the epidural space and positioning therein. Methods of using same are also provided.
