Pain relief by wound infiltration with bupivacaine or high-dose ropivacaine after inguinal hernia repair

Wound infiltration with bupivacaine is often used for pain relief after inguinal hernia surgery. We hypothesized that the lower systemic toxicity of another long-acting local anesthetic of similar potency (ropivacaine) would make it possible to increase the dose to above that recommended for bupivacaine and thereby achieve more effective pain control.

Elective unilateral open hernia repair was performed on 144 patients at 4 hospitals. Surgery was performed under general anesthesia and, in a double-blind manner, the operating field was infiltrated with 40 mL ropivacaine 7.5 mg/mL (in = 73) or bupivacaine 2.5 mg/mL (n = 71 ) for postoperative pain relief. Pain at rest, on mobilization, and on coughing was assessed repeatedly during 24 hours using a visual analog scale. The patients' ability to walk and the need for supplementary analgesics were also recorded.

No statistically significant differences were found between the two groups with respect to pain scores, which the patients reported to be less than 15% (median) of the worst pain imaginable in all examinations performed at rest, or in the consumption of supplementary analgesics. Those who received ropivacaine could walk with no or only minor problems at an earlier stage than the bupivacaine patients (P < .03). Both treatments were well tolerated.

Wound infiltration with long-acting local anesthetics resulted in low pain scores after hernia surgery. Bupivacaine 100 mg was as effective as ropivacaine 300 mg.