[Inadvertant epidural placement of a psoas compartment catheter. Case report of a rare complication].

Due to total knee replacement, a 67-year-old female patient had received a combination of general anesthesia and continuous psoas compartment block. An epidural block was detected postoperatively. An X-ray after the injection of contrast medium showed a typical epidurography with the catheter tip projecting into the epidural space. After drawing back the catheter, another X-ray showed a correct placement of the catheter and a typical spreading of the contrast medium and the catheter could be used for pain relief. In retrospect, it turned out that the catheter had been placed too far over the tip of the stimulation needle. The recommendations of different authors on this problem vary and are actually quite contradictive. We would recommend not to place the catheter further than 5 cm over the tip of the needle. After the first injection the quality of monitoring should correspond with that of an epidural anesthesia. In doubtful cases an injection of contrast medium and an X-ray can be performed.