Effect of Local Anesthetic Infiltration for Postoperative Pain Control in Laparoscopic Abdominal Surgery: A Prospective Randomized Study

Overview

Brief Summary Postoperative pain remains a common problem after laparoscopic abdominal surgery despite the minimally invasive nature of these procedures. Pain mainly arises from the trocar insertion sites, tissue manipulation, and the effects of pneumoperitoneum. Although systemic analgesics are routinely used, they may not provide adequate pain relief and can be associated with adverse effects. This prospective randomized controlled trial aims to evaluate whether pre-incisional infiltration of bupivacaine at laparoscopic trocar insertion sites reduces postoperative pain compared with standard care without local anesthetic infiltration. A total of 166 adult patients undergoing elective laparoscopic abdominal surgery will be randomly assigned to receive either local bupivacaine infiltration before skin incision or no local anesthetic infiltration. All participants will receive the same standard perioperative care and postoperative analgesic regimen. The primary outcome is postoperative pain intensity measured using the Visual Analog Scale (VAS) during the first 24 hours after surgery. Secondary outcomes include the time to first rescue analgesic, total opioid consumption within the first 24 hours, and overall postoperative pain control. The results of this study may help determine whether local bupivacaine infiltration is an effective, simple, and low-cost addition to multimodal analgesia for patients undergoing laparoscopic abdominal surgery.

Detailed description

Detailed Description

Laparoscopic abdominal surgery is widely performed because it is associated with reduced surgical trauma, shorter hospital stays, and faster recovery compared with open procedures. Despite these advantages, postoperative pain remains a significant concern. Pain after laparoscopy is multifactorial, resulting from trocar insertion, tissue manipulation, and pneumoperitoneum. Although multimodal analgesia is routinely employed, optimal management of trocar-site pain remains uncertain.

Local infiltration of surgical incision sites with long-acting local anesthetics such as bupivacaine has been proposed as a simple and inexpensive method of reducing postoperative pain and opioid requirements. However, published randomized trials have reported inconsistent findings regarding the magnitude of benefit, and variations in infiltration technique, timing, and dosage have limited the establishment of standardized recommendations. Additional prospective randomized studies are needed to evaluate the effectiveness of this intervention in different clinical settings.

This single-center prospective randomized controlled trial will be conducted in the Department of General Surgery, Allied Hospital, Faisalabad. Adult patients undergoing elective laparoscopic abdominal surgery will be randomly allocated in a 1:1 ratio to receive either pre-incisional infiltration of diluted bupivacaine at planned trocar insertion sites or no local anesthetic infiltration. All participants will receive the institution's standard perioperative management and postoperative analgesic protocol.

The study aims to determine whether pre-incisional local bupivacaine infiltration provides superior postoperative pain control during the first 24 hours after laparoscopic abdominal surgery. Pain intensity will be assessed using the Visual Analog Scale (VAS), while opioid consumption and time to first rescue analgesia will be evaluated as secondary measures of analgesic efficacy. The findings may help clarify the role of local anesthetic infiltration as part of multimodal postoperative pain management and contribute evidence to guide clinical practice in patients undergoing laparoscopic abdominal surgery.

Interventions

• Drug Bupivacaine
  Bupivacaine 0.5% (5 mg/mL), 20 mL diluted with 20 mL of normal saline to achieve a final concentration of 0.25% (40 mL total volume). The solution will be infiltrated equally into the planned laparoscopic trocar insertion sites before skin incision.
• Other Standard Perioperative Analgesia
  Standard perioperative analgesia according to the institutional protocol, including intravenous paracetamol 1 g every 8 hours and intravenous tramadol 50 mg administered as rescue analgesia for patients with a Visual Analog Scale (VAS) pain score ≥4 during the first 24 hours after surgery.

Primary outcome measures

• Postoperative Pain Intensity [Time frame: At 1, 6, 12, and 24 hours after surgery]

Secondary outcome measures (2)

• Time to First Rescue Analgesia [Time frame: Within 24 hours after surgery]
• Total Opioid Consumption [Time frame: Within 24 hours after surgery]

Eligibility criteria

Inclusion criteria

Adults aged 18 to 60 years. Scheduled for elective laparoscopic abdominal surgery (e.g., cholecystectomy, appendectomy, or hernia repair).

American Society of Anesthesiologists (ASA) physical status I or II. Able to understand and use the Visual Analog Scale (VAS) for pain assessment. Willing and able to provide written informed consent.

Exclusion criteria

Intraoperative conversion to open laparotomy. Known allergy, hypersensitivity, or contraindication to bupivacaine or other amide local anesthetics.

Pregnancy or breastfeeding. History of chronic pain syndromes or regular use of opioid or non-opioid analgesics before surgery.

History of substance abuse or severe psychiatric disorders that may affect pain perception.

Local skin infection at the planned trocar insertion sites.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Treatment

Study locations

Pakistan · 1 center

• Allied Hospital Faisalabad — Faisalābad

Publications

• Nakngam N, Wasinghon P, Ratanakaew A. Bupivacaine Local Infiltration at Trocar Insertion Sites after Gynecologic Laparoscopic Surgery: A Randomized, Double-blind, Placebo-Controlled Trial. Journal of the Medical Association of Thailand. 2024;107(3):185-190. DOI: 10.35755/jmedassocthai.2024.3.13955
• Gluck O, Barber E, Feldstein O, Tal O, Kerner R, Keidar R, Wolfson I, Ginath S, Bar J, Sagiv R. The effect of subcutaneous and intraperitoneal anesthesia on post laparoscopic pain: a randomized controlled trial. Sci Rep. 2021 Jan 8;11(1):81. doi: 10.1038/s41598-020-80130-6. PMID 33420214
• Einarsson JI, Sun J, Orav J, Young AE. Local analgesia in laparoscopy: a randomized trial. Obstet Gynecol. 2004 Dec;104(6):1335-9. doi: 10.1097/01.AOG.0000146283.90934.fd. PMID 15572499

Identifiers

NCT: NCT07747584 · 48ERC/FMU/2025-26/300

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗