A comparison of three different concentrations of ropivacaine with fentanyl for patient-controlled epidural analgesia.

BACKGROUND: The optimal concentration of ropivacaine in combination with fentanyl for patient-controlled epidural analgesia focusing on preservation of bowel function, analgesia, and motor function remains unclear. METHODS: Three hundred-twelve women scheduled to undergo gynecologic lower abdominal surgery, were randomly allocated to receive ropivacaine 0.05, 0.075, or 0.1% in combination with fentanyl 4 mu g/mL and droperidol 25 mu g/mL. The settings of patient-controlled epidural analgesia were as follows: initial loading volume 5 mL, background infusion 2 mL/h during night-time, no background infusion during daytime, bolus volume 2 mL, and lockout interval 10 min. Bowel function was evaluated by the first passage of flatus and feces. Pain was assessed with a visual analog scale, and motor function was examined by modified Bromage scale. Data were collected in the evening on the day of surgery, in the morning and in the evening on the first postoperative day, and in the morning on the second postoperative day. RESULTS: Gastrointestinal motility was not different among the three groups. All three solutions produced equivalent analgesia and no motor blockade. CONCLUSION: We conclude that ropivacaine 0.05% is sufficient to preserve gastrointestinal motility, and provides excellent postoperative pain relief without motor, blockade.