A bending tool for use with a human hand for bending the distal extremity of a guide tube of a medical device having a needle assembly slidably mounted in the guide tube. The distal extremity of the guide tube has a tip. The bending tool is comprised of a shaft sized so that it is adapted to be grasped by the human hand to serve as a handle. The shaft has proximal and distal extremities and a longitudinal axis. A bending construction is mounted on the distal extremity of the shaft and provides a curved bending surface having width and a length and having a proximal and a distal extremity and extending at an angle with respect to the longitudinal axis. The bending construction also has an abutment surface at the distal extremity of the curved surface and extending generally perpendicular to the curved surface. The abutment surface has a hole therein extending in a direction generally perpendicular to the abutment surface and is sized so that it is adapted to receive the tip of the guide tube with the guide tube engaging the curved surface to permit bending of the guide tube by a swinging movement of the shaft in a direction at right angles to the abutment surface.