Analgesia for shock wave lithotripsy.

PURPOSE: We evaluated the effectiveness of and patient preference for analgesia used during shock wave lithotripsy by comparing diclofenac alone with a combination of diclofenac and patient controlled analgesia, that is alfentanil.

MATERIALS AND METHODS: A total of 64 patients were treated using a Lithotriptor S (Dornier Medical Systems, Marietta, Georgia) and randomized to receive diclofenac alone or combined with an alfentanil patient controlled analgesia pump. If treated twice, they crossed over to the alternative form of analgesia. A record was maintained of the site and size of the stone, maximum power achieved, number of shocks, amount of alfentanil used and need for additional analgesia. After treatment patients scored on a visual analog scale the maximum level of pain and satisfaction with analgesia.

RESULTS: There was no difference in the mean size of the stone treated (8.6 and 7.5 mm.), energy level (71% and 71% or approximately 17 kV.) or number of shocks (3,000 and 2,900, respectively) in the groups. Only 2 patients in the diclofenac group required additional analgesia and there were no significant side effects from either treatment. The mean pain scores were not significantly different in the diclofenac and patient controlled analgesia groups (3.54 and 2.93, respectively, (p = 0.34), although those on patient controlled analgesia were more satisfied (7.72 versus 9.14, p = 0.04). Of the 38 patients who presented twice 58% preferred diclofenac alone.

CONCLUSIONS: This study suggests that there is no significant difference in the level of pain experienced with diclofenac alone or when combined with an alfentanil patient controlled analgesia pump during shock wave lithotripsy. However, patients are more satisfied with treatment when a patient controlled analgesia pump is available.