A randomized controlled trial of preperitoneal bupivacaine instillation for reducing pain fillowing laparoscopic inguinal herniorrhaphy

Abstract

Objective: To determine the effectiveness of bupivacaine instillation into the preperitoneal space following laparoscopic herniorrhaphy. Design: Randomized controlled trial, double blinded Setting: The elective surgery in a medical school Participants: Forty patients, who had an inguinal hernia with no complication, unilateral or bilateral and recurrence or no recurrence after previous hernia repair were randomly assigned to receive bupivacaine (n = 19) and normal saline (n =21). The intervention or placebo was instilled into preperitoneal space after totally extraperitoneal laparoscopic herniorrhaphy by the same surgeon who was blinded to the intervention. Main outcome measures: Pain intensity was assessed by using visual analogue scale and verbal rating scale after 1, 2, 6, 12 and 24 hours postoperatively by the same nurse who was blinded to the intervention. Results: For bupivacaine and placebo group, mean of pain score were 3.5 vs. 5.2 respectively after 1 hour (p= 0.059), 2.9 vs. 4.5 respectively after 2 hours (p=0.117), 2.1 vs. 3.2 respectively after 6 hours (p= 0.101), 1.5 vs. 2.7 respectively after 12 hours (p= 0.145) and 1.6 vs. 2.0 respectively after 24 hour (p= 0.672). The complications developed in 4 patients (2 seroma, 1urinary retention and 1 arrhythmia) in bupivacaine group and 7 patients (5 seroma, 1 urinary retention and 1 ileus) in placebo group, which are not significant different. Conclusions: There is no strong evidence to confirm that bupivacaine instillation into preperitoneal space after laparoscopic herniorrhaphy can reduce postoperative pain.