Abstract: A catheter set including an epidural cannula having a dull leading end; i.e., a leading end without a cutting grinding. A first trocar, only the tip of which projects beyond the epidural cannula, may be inserted into the epidural cannula for puncturing. The leading end of the epidural cannula may abut against the dura without the dura being perforated by the tip of the trocar. Thereafter, the first trocar may be removed and the dura may be punctured by a second trocar which is longer than the first trocar and which may be inserted into the cannula. After removal of the second trocar, a catheter may be inserted through the punctured dura into the spinal area, using the epidural cannula as a guide cannula. The puncture caused by the second trocar is entirely closed by the catheter. This opening remains small, since the epidural cannual has no grinding to cut the dura.