Study on analgesic effectiveness of ultrasound-guided transverse abdominis plane block using different volumes and concentrations of levobupivacaine in laparoscopic cholecystectomy

Background: Laparoscopic cholecystectomy, though less invasive than open surgery, still causes notable post-operative pain from port site trauma and abdominal distension. Regional techniques such as transverse abdominis plane (TAP) block reduce both intraoperative and postoperative opioid use, lowering the side effects. Aims and Objective: This study evaluated the analgesic effectiveness of TAP block using different volumes and concentrations of levobupivacaine in patients undergoing laparoscopic cholecystectomy. Materials and Methods: The study was a prospective randomized control intervention study conducted on 110 patients with similar demographics undergoing laparoscopic cholecystectomy under general anesthesia. TAP block was given bilaterally with 20 mL of local anesthetic (50 mg 0.5% levobupivacaine +10 mL saline solution) in Group A and 30 mL of local anesthetic (50 mg 0.5% levobupivacaine +20 mL saline solution) in Group B, after stabilization of the patient. Analgesic effectiveness in the two groups was compared intraoperatively by vitals at regular intervals and the total consumption of injection fentanyl. Similarly, post-operative analgesia in the two groups was compared based on Visual Analog Scale (VAS) scores, time to first rescue analgesic, and total rescue analgesic required. Results: The patients of Group B receiving 30 mL had significantly better analgesia compared to Group A, who received 20 mL volume. This was determined through various parameters, including intraoperative vitals, fentanyl consumption during surgery, VAS scores (at 20 min, 12 h, and 24 h), time to first rescue analgesic requirement, and total rescue analgesic used. Conclusion: The volume of local anesthetic used in ultrasound-guided TAP blocks played a crucial role in determining analgesic efficacy for patients undergoing laparoscopic cholecystectomy. Thus, optimizing volume, rather than relying solely on concentration, may enhance the clinical effectiveness of TAP blocks while allowing for safer dosing strategies.