A regional anesthesia catheter used with a guide such as for example a needle cannula has a distal portion integrally connected to a main portion of the catheter by a junction portion that has a cross-sectional profile different from the distal and main portions, so as to predispose the distal portion of the catheter to move in a given direction when the distal portion is not guided by or constrained by the needle cannula. The cross-sectional profile of the junction portion may be configured in a particular shape, or be constructed to have a flexibility that predisposes the distal portion to bend, curve or move toward a given direction. Once the predisposed direction to which the distal end of the catheter points is known, a physician can readily orient the catheter relative to the needle cannula so that once the distal end of the catheter exits the distal tip of the needle cannula, with the cannula already placed in a position proximate to the desired location to which the distal end of the catheter is to be placed, the physician can readily place the distal end of the catheter at the desired location within the patient. Instead of only one junction portion, a number of portions of a catheter may be configured to bend at a predefined direction. Further, a catheter may be configured to have a cross sectional profile or a predefined flexibility along its entire length that causes the catheter to bend, curve or move in a predefined direction.