Comparative Study of Ultrasound-guided Post-Operative Analgesia using Opioid versus Opioid-free Analgesia in Elective Abdominal Surgeries under Spinal Anaesthesia

Author(s): Prashant Gupta, Sarika Shrivastava, Shreyash Kesarwani, Amit Tondon, Arpita Saxena, Manish Goyal, Tilok Chand, Apurva Abhinandan Mittal

Introduction: The reliance on opioid-based analgesia for postoperative pain control, while effective, is frequently accompanied by adverse effects such as respiratory depression, postoperative nausea and vomiting, delayed recovery, and the potential for opioid dependence. In the context of enhanced recovery protocols, there is growing interest in opioid-sparing and opioid-free analgesic strategies.

Objectives: This study aimed to evaluate the comparative efficacy of opioid based versus opioid-free postoperative analgesia in patients undergoing elective lower abdominal surgeries under spinal anesthesia. Particular emphasis was placed on assessing pain scores, hemodynamic parameters, incidence of PONV, and total opioid consumption within the first 24 hours postoperatively.

Methods: A prospective observational study was conducted at a tertiary care institution involving adult patients (aged 18-60 years) undergoing elective lower abdominal surgery under spinal anesthesia. Participants were stratified into two groups: Group A received conventional opioid-based analgesia with intravenous tramadol, whereas Group B received an opioid-free regimen incorporating a single-injection, ultrasound-guided erector spinae plane (ESP) block at the T9 level using 20 ml of 0.25% bupivacaine. Postoperative pain was assessed using the Visual Analogue Scale (VAS) at 2, 4, 12, and 24 hours. Hemodynamic parameters, PONV incidence, and total opioid consumption were systematically documented. Results: The opioid-free group demonstrated significantly lower VAS scores at all measured time points (p < 0.05), improved hemodynamic stability, and a markedly reduced incidence of PONV. The requirement for rescue analgesia was also substantially diminished in this group compared to the opioid-based cohort.

Conclusion: Ultrasound-guided ESP block provides effective and sustained postoperative analgesia in lower abdominal surgeries performed under spinal anesthesia. The technique facilitates opioid-free recovery, minimizes opioid associated side effects, and supports enhanced postoperative outcomes, thereby underscoring its value as an integral component of multimodal analgesia protocols.