Continuous local anesthetic infusion for pain management after outpatient inguinal herniorrhaphy

Background: The purpose of the present study is to compare postoperative pain and functional outcomes in patients undergoing inguinal herniorrhaphy who receive a continuous wound infusion of bupivacaine to those who receive an infusion of saline. Methods: A prospective, randomized, blinded, placebo-controlled trial was conducted in adults undergoing outpatient inguinal herniorrhaphy. Patients received saline or bupivacaine through a disposable infusion pump for 60 hours postoperatively. Pain outcomes were assessed, as were functional outcomes (activity, return of bowel function) and side effects. Results: On postoperative day 1, patients who received bupivacaine had lower ratings for worst pain than patients who received saline, (5.0 +/- 2.3 vs 6.7 +/- 2.2, P=.002). On day 1, least pain ratings were also lower, and patients ambulated more frequently than those who received placebo. There were no differences between groups from postoperative days 2 to 5. There were no differences between groups in the amount of hydrocodone consumption. Conclusions: Continuous infusion of local anesthetic after inguinal herniorrhaphy provides modest improvements in pain scores and functional outcomes when compared with placebo. However, these effects are limited to the first postoperative day only. The additional costs associated with this intervention may limit its widespread use in clinical practice.