Perioperative Intravenous Lignocaine and Postoperative Analgesic Requirements Following Abdominal Surgery: A Descriptive Observational Study

Abstract

Background: Postoperative pain after abdominal surgery often necessitates substantial opioid administration, particularly after prolonged open procedures. Intravenous lignocaine has been incorporated into multimodal anaesthetic regimens because of its analgesic, antihyperalgesic, and anti-inflammatory properties. However, postoperative analgesic requirements may vary considerably according to surgical magnitude and operative approach.

Objectives: To describe postoperative pain trajectories, opioid requirements, rescue analgesia, postoperative nausea and vomiting, and hospital stay among patients receiving intravenous lignocaine as part of general anaesthesia for abdominal surgery. A secondary objective was to compare these outcomes between laparoscopic and open surgical approaches.

Methods: This descriptive observational study included 80 adults undergoing abdominal surgery under general anaesthesia with intraoperative intravenous lignocaine. Lignocaine was administered as a 60 mg intravenous bolus followed by an infusion at 1.5 mg/kg/h. Pain intensity was measured using a 0-10 visual analogue scale at post-anaesthesia care unit admission and at 2, 6, 12, 24, and 48 hours. Morphine-equivalent opioid consumption, rescue analgesia, postoperative nausea and vomiting, and length of hospital stay were recorded. Repeated pain scores were compared using the Friedman test. Outcomes between laparoscopic and open procedures were examined using the Mann-Whitney U test and Fisher’s exact test.

Results: The mean age was 54.94±11.92 years, and 40 participants each were male and female. Fifty procedures (62.5%) were laparoscopic and 30 (37.5%) were open. Mean pain scores declined from 4.38±1.84 at post-anaesthesia care unit admission to 3.54±1.71 at 2 hours, 3.16±1.73 at 6 hours, 2.55±1.67 at 12 hours, 1.95±1.47 at 24 hours, and 1.14±1.29 at 48 hours (Friedman χ²=378.889, p<0.001). Mean morphine-equivalent opioid consumption was 27.75±18.57 mg during 0-24 hours and 15.62±14.97 mg during 24-48 hours. Rescue analgesia was required in 30 patients (37.5%), while postoperative nausea and vomiting occurred in 21 (26.3%). Compared with laparoscopic procedures, open procedures were associated with higher 0-24-hour opioid consumption (46.67±14.61 vs 16.40±8.89 mg), rescue analgesia requirement (80.0% vs 12.0%), postoperative nausea and vomiting (66.7% vs 2.0%), and hospital stay (7.87±2.83 vs 2.72±1.34 days), with all comparisons yielding p<0.001.

Conclusion: Pain scores declined progressively during the first 48 postoperative hours among abdominal surgical patients receiving intraoperative intravenous lignocaine. Nevertheless, substantial analgesic requirements persisted after open and prolonged operations. Because the study lacked a non-lignocaine comparator, the findings describe postoperative recovery under a lignocaine-containing multimodal regimen rather than establishing an independent opioid-sparing effect.