Abstract: A regulating device for adjusting the length of a combined spinal epidural needle and the method of practicing same is disclosed. In one variant, the regulating device features a pair of substantially concentrically disposed sliding members to which each of the epidural needle and spinal needle may be fitted. A locking actuation tab fitted to one of the sliding members is provided to control axial movement between the sliding members, thereby regulating the extension of the spinal needle relative to the epidural needle. The sliding members may be configured in a variety of shapes or dimensions to accommodate various combinations of spinal and epidural needles. The device may be provided pre-assembled with either one or both of the spinal needle or epidural needle, or it may be employed with a spinal needle, epidural needle, or both separately sourced.