Post-herniorrhaphy pain in outpatients after preincision ilioinguinal-hypogastric nerve block during monitored anaesthesia care

Abstract

The objective of this study was to evaluate the effect of an ilioinguinal-hypogastric nerve block (IHNB) with bupivacaine 0.25% on the postoperative analgesic requirement and recovery profile in outpatients undergoing inguinal herniorrhaphy with local anaesthetic infiltration. Thirty consenting healthy men undergoing elective unilateral inguinal herniorrhaphy procedures were randomly assigned to receive an IHNB with either saline or bupivacaine according to a double-blind, IRB-approved protocol. All patients received midazolam, 2 mg iv, and fentanyl 25 μg iv, prior to injection of 30 ml of either bupivacaine 0.25% or saline through the oblique muscle approximately 1.5 cm medial to the anterior superior iliac spine. Subsequently, the surgeon infiltrated the incision site with a lidocaine 1% solution. Sedation was maintained during the operation with a variable-rate propofol infusion, 25-140 μg · kg-1 · min-1. No significant differences were noted in the intraoperative doses of lidocaine, propofol and fentanyl in the two treatment groups. However, the pain visual analogue score at 30 min after entering the PACU was lower in the bupivacaine (versus saline) group (P < 0.05). Although the times to ambulation (86 ± 18 vs 99 ± 27 min) and being judged "fit for discharge" (112 ± 49 vs 126 ± 30 min) were similar in the two groups, the bupivacaine-treated (vs saline) patients required less oral analgesic medication after discharge (46% vs 85%). We concluded that the use of an ilioinguinal-hypogastric nerve block with bupivacaine 0.25% as an adjuvant during inguinal herniorrhaphy under monitored anaesthesia care decreased pain in the PACU and oral analgesic requirements after discharge from the day-surgery unit. © 1995 Canadian Anesthesiologists.