Comparison of post operative analgesia between Nalbuphine and Fentanyl as adjuvant with intrathecal Levobupivacaine for lower abdominal gynaecological surgeries

For lower abdominal gynaecological procedures, spinal anaesthetic is the recommended anaesthetic approach because it offers the advantages of a quick onset of effect, full motor blocking, and ease of application. It also requires a low amount of local anaesthetic medication and has a lower frequency of unsuccessful blocks, but it is insufficient to give post-operative analgesia. Adjuvants, such as dexmeditomedine, fentanyl, and nalbuphine, have a synergistic effect and amplify sensory block without increasing sympathetic block when added to local anaesthetics for intrathecal administration. This leads to better hemodynamic stability with fewer adverse effects, a reduction in the dosage of local anaesthetic medication, and aids in post-operative analgesia.

Fentanyl belongs to phenypiperidine derivative synthetic opiod. It is structurally similar to Meperidine. It is a pure mu receptor agonist. It is lipophilic in nature, has rapid onset of action and does do not cause respiratory depression following intrathecal administration.. It improves anaesthetic quality without much complications. It prolongs duration of anesthesia as well as depression of ventilation after intrathecal administartion. The typical adverse effects of mu agonists include drowsiness, nausea, vomiting, urine retention, and respiratory depression. Nalbuphine is a mixed agonist and antagonist opioid drug. Agonist to kappa and antagonist to mu receptor. It is similar with oxymorphone and naloxone in terms of structure. It offers analgesia without the negative side effects associated with mu receptor agonist activity. Almost all general anaesthesia and regional anaesthesia techniques work with it. Nalbuphine causes analgesia by attaching to kappa receptors found throughout the spinal cord and brain.(1)

Levobupivacaine is a local anaesthetic medication from the amide family. It is bupivacaine's S-enantiomer, which is less caridotoxic and neurotoxic and equally potent as compared to bupivacaine. It also shows early motor recovery.  Many studies have compared intrathecal nalbuphine and fentanyl with levobupvacaine and its effects on post-operative analgesia.

The goal of this research is to compare the efficacy of fentanyl & nalbuphine as adjuvants with intrathecal levobupivacaine for post-operative analgesia following lower abdominal gynaecological surgeries.