LIA with vs. without an additional intraarticular catheter- Results of a RCT

AIMS AND OBJECTIVES: Local infiltration analgesia (LIA) is meanwhile worldwide established and scientifically proven in perioperative treatment of TKA. Single-shot is the mostly used option. However, after the local analgesia has subsided, at the latest after the day of surgery, the pain is usually present and affects rapid mobilization and rehabilitation. Long-acting medications for LIA have not proved to be effective and there are barely data on intra-articular continuous analgesia. We present a randomized controlled trial which compares the LIA with and without additional continuous analgesia using an intraarticular catheter. MATERIALS AND METHODS: 50 patients with TKA were randomized and included in the study. All patients received the same implant system without patellar resurfacing, without tourniquet or drains. The operation was performed by the same surgeon and postoperative treatment was identical. Both groups received a general anesthesia with laryngeal mask. A group of 25 patients received a single-shot LIA containing 150 ml bupivacaine (0.2%) and morphine (20 mg). The other group, also 25 patients, received the same single-shot LIA and an intraarticular catheter (350 ml) for 3 days with continuous infiltration (8ml/h) of bupivacaine (0.2%) and morphine (20 mg per 200 ml bupivacaine) . The following parameters were recorded preoperatively and postoperatively: VAS, additionally analgetics / opioids. Also included were complications such as infections, postoperative falls and DVT. RESULTS: The average operating time was 46 min. There were no complications or reinterventions. The results were not significantly different during the first day, but for day 2 to 4 VAS was significantly better and additional analgetics / opioids were significantly less (p <0.05) in the group with additional catheters. On days 5 and 6, the results again were comparable. CONCLUSION: There was a superiority of the additional intra-articular catheter for some days in the perioperative treatment of TKA.