Comparison of the Efficacy of Intraperitoneal Instillation of Fentanyl Versus Nalbuphine As Adjuvants to Bupivacaine for Postoperative Pain Relief in Patients Undergoing Laparoscopic Cholecystectomy

Laparoscopic cholecystectomy (LC) is recognized as the gold standard for managing gallbladder stones due to its numerous advantages over open surgery . These benefits include quicker and easier recovery, reduced operative morbidity, less postoperative pain, shorter convalescence, and overall lower costs

Intraperitoneal administration of local anesthetics is used by many surgeons as a method to provide effective pain relief while minimizing the adverse effects of systemic analgesics, including NSAIDs and opioids. The rationale for this route of administration is that the local anesthetics will block the visceral nociceptive conduction from peritoneum. In addition, systemic absorption from the large peritoneal surface may occur, providing additional mechanism of analgesia . This technique was first evaluated in patients undergoing gynecological laparoscopy and showed reduction in postoperative shoulder pain . With the possibility that a similar analgesic effect might be achieved in LC, several trials assessing the efficacy of Intraperitoneal local anesthetics in LC were carried out with conflicting results, regarding severity of postoperative pain, duration of analgesia, and total analgesic consumption in 24 h. The difference in outcome of studies on instillation of local anesthetics may result from dose, volume, or concentration of the drug; timing of instillation (before or after surgery); site of administration (subdiaphragmatic, over gall bladder bed, and/or port infiltration); and instillation in Trendelenberg's versus supine position .

Fentanyl and nalbuphine are two widely used opioids considered for pain management . Fentanyl is a potent synthetic opioid similar to morphine but produces analgesia to a greater extent. This robust pharmacologic agent is typically 50 to 100 times more potent than morphine . it is renowned for its rapid onset and strong analgesic properties. It is extensively used in clinical settings to manage acute pain .

On the other hand, nalbuphine, a mixed agonist-antagonist opioid, acts as an antagonist at μ-receptors and agonist at k-receptors that work reasonably potent analgesia. It offers effective pain relief, particularly with a lower risk of respiratory depression. It also provides prolonged analgesia and is associated with fewer side effects, such as pruritus, nausea, and vomiting, than fentanyl .

This route of administration is noninvasive, simple to perform, does not involve additional neuraxial block, and is particularly suited for the practice of ambulatory anesthesia. However, duration of analgesia may be limited for few hours. So, addition of adjuvants such as narcotics, α2 agonists, or NSAIDs has been proposed to prolong the postoperative analgesia