Effect of Intraperitoneal Bupivacaine with Dexmedotomidine or Fentanyl for Post-Operative Analgesia Following Laparoscopy in Pediatric Patients

Laparoscopic procedures have many advantages over open procedures such as lesser hemorrhage , better cosmetic results, lesser postoperative pain and shorter recovery time leading to a shorter hospital stay and less expenditure . Laparoscopic procedures are associated with postoperative pain affecting early ambulation of the patient. Pain in laparoscopic surgery results from stretching of the abdominal cavity, peritoneal inflammation, diaphragmatic irritation and residual carbon dioxide (CO2) in the peritoneal cavity . Peritoneal irritation by carbonic acid (formed by reaction between carbon dioxide CO2 and water) and the creation of space between the liver and diaphragm by residual pneumoperitoneum has been implicated for visceral and shoulder tip pain. Humidity and volume of the insufflated gas, wound size, and trauma to the parietal peritoneum may also be responsible for this pain. A multimodal approach is required to alleviate all three types of pain which includes parenteral NSAIDs, opioids, and postoperative intraperitoneal local anesthetic instillation, port-site infiltration of local anesthetic, intra-peritoneal saline, removal of insufflation gas, gas drains, low-pressure abdominal insufflations, acetazolamide administration and use of N2O in place of CO2, etc. Intraperitoneal local anesthetic (IPLA) appears promising in pediatric surgery although the high absorptive capacity of the peritoneum and high peritoneal surface area in children. Hence, the delivery of an effective dose without toxicity in children could be challenging. Fentanyl selectively binds to the mu-receptor in the central nervous system (CNS). Stimulation of the mu-subtype opioid receptor stimulates the exchange of GTP for GDP on the G-protein complex and subsequently inhibits adenylate cyclase, so decreasing in intracellular cAMP and leads to a reduction in the release of neurotransmitters. It was found that administering either fentanyl or ketamine as an LA adjuvant dramatically speed up the onset of anesthesia, prolonged the duration of lid akinesia, increased the duration of globe akinesia, and lengthened the time for the first request of postoperative analgesia. Opioids, in conjunction with local anesthetics, improve the quality of intraoperative analgesia and prolong the duration of postoperative analgesia. Although morphine was the first opioid used, a wide variety of clinically relevant side effects, especially respiratory depression, limited its utility. In contrast, a favorable pharmacokinetic and pharmacodynamic profile of lipophilic opiates (fentanyl) proved to be a better alternative as their lipophilicity leads to rapid uptake and faster clinical onset of action and short duration of action. Dexmedetomidine (alpha-2 adrenergic agonists) has become one of the frequently used drugs in anesthesia as it has been reported to provide analgesia, anxiolysis, and an anesthetic-sparing action with minimal respiratory depression plus its sedative effect that mimics natural sleep. Intraperitoneal instillation of dexmedetomidine with bupivacaine reduces the pain after elective laparoscopy in adults as compared to that with bupivacaine alone or with tramadol. In addition, the postoperative requirement for rescue analgesia is reduced. The purpose of the study is to assess and compare the analgesic effectiveness of intraperitoneal bupivacaine in paediatric patients with either fentanyl or Dexmedotomidine.