Effects of Intraperitoneal Local Anaesthetics Bupivacaine and Ropivacaine versus Placebo on Postoperative Pain after Laparoscopic Cholecystectomy: A Randomised Double Blind Study.

Introduction: Laparoscopic Cholecystectomy (LC) is the most frequently performed elective daycare surgery and provision of postoperative pain relief is of importance. After laparoscopic cholecystectomy shoulder and abdominal pain causes considerable distress. Visceral pain during coughing, respiration and mobilization increases morbidity, hospital stay and costs.

Aim: To compare the analgesic efficacy of intraperitoneally instilled equipotent concentrations of bupivacaine and ropivacaine versus placebo in relieving postoperative pain after laparoscopic cholecystectomy when used as a part of multimodal analgesia.

Materials And Methods: In this randomised, prospective, double blind, placebo controlled study, 90 ASA Class I or II patients were randomly divided into three groups of 30 each. Group S received intraperitoneal infiltration with 35 ml of 0.9% normal saline, Group B with 35 ml of 0.25% bupivacaine and Group R with 35 ml of 0.375% ropivacaine. All groups received standard general endotracheal anaesthesia and analgesia with IV paracetamol 15 mg/kg and diclofenac 1.5 mg/kg. Numerical Rating Scale (NRS) score of analgesia at rest and on cough/movement, duration of analgesia, haemodynamic parameters, need for a rescue analgesic (IV tramadol 1 mg/kg) was recorded and adverse effects of procedure and drugs if any were monitored. Data was analysed with SPSS statistical software version 21.0. One way ANOVA or the Kruskal-Wallis test was used to compare continuous data across all three groups as appropriate. Subsequent analysis of continuous data between two groups was achieved by Tukey's post hoc test. Significance was accepted as p<0.05.

Results: The mean NRS was <5 till only four hours in Group S, till eight hours in Group B and till 16 hours in Group R. The duration of analgesia was 13.47±1.38 hours in Group R, 7.93±1.44 hours in Group B and 4.47±0.86 hours in Group S.

Conclusion: Intraperitoneal infiltration of LA significantly reduces pain intensity scores in the early postoperative period after LC surgery and helps in improving the postoperative recovery profile and outcome. This makes LC surgery more amenable to day care surgical setup. Ropivacaine (0.375%) is more efficacious, longer acting with a higher intensity of postoperative analgesia than bupivacaine (0.25%).