Assessment of the Efficacy of Nalbuphine as an Adjuvant to Intrathecal Bupivacaine in Endoscopic Urological Surgeries for the Prolongation of Postoperative Analgesia

TL;DR

This study shows that adding nalbuphine to bupivacaine during spinal anesthesia improves pain relief after urological surgeries without major side effects.

Contribution

The study demonstrates that intrathecal nalbuphine 1.5 mg prolongs postoperative analgesia in endoscopic urological surgeries.

Findings

Nalbuphine caused earlier onset of sensory and motor block and delayed regression.

Patients with nalbuphine had significantly longer postoperative analgesia (264.97 minutes vs. 198.50 minutes).

No adverse effects on vital signs or complications like urinary retention or pruritus were observed.

Abstract

Background

In anaesthesiology, intrathecal drugs play pivotal roles in spinal anaesthesia. Despite their ability to induce a high sensory block, bupivacaine alone may not be adequate for postoperative analgesia. It often requires a substantial dose of postoperative rescue analgesia to manage pain effectively. Thus, we studied the efficacy of nalbuphine 1.5 mg injected intrathecally as an adjuvant in endoscopic urological surgery.

Materials and methods

Sixty patients undergoing endoscopic urological surgery were equally divided into two study groups: group B (injection 0.5% hyperbaric bupivacaine 15 mg (3 ml) plus sterile NS 0.15 ml) and group N (injection 0.5% hyperbaric bupivacaine 15 mg (3 ml)+nalbuphine 1.5 mg (0.15 ml)). The first appearance of the sensory and motor blockages and duration required to attain complete sensory and motor threshold was noted. All vitals were recorded. After surgery, it was recorded when the patient first needed rescue analgesia (injection paracetamol 1 gm IV). Any adverse effects were recorded and addressed. The statistical analysis was conducted using IBM SPSS Statistics for Windows, V. 22.0 (IBM Corp., Armonk, NY), with p<0.05 indicating significance in both groups' operations.

Results

Intrathecal nalbuphine as an adjuvant caused an earlier onset of sensory and motor inhibition, delayed two-segment regression, and prolonged postoperative anaesthesia. The control group experienced sensory block at 3.33±0.61 minutes, while the nalbuphine group had a mean onset of 2.66±0.92 minutes (p=0.001). The patient who received nalbuphine had a mean regression time of 119.60±14.549 minutes, whereas the bupivacaine group had a mean regression time of 88.43±17.196 minutes. Group N had a considerably longer duration of postoperative analgesia, lasting 264.97 minutes, compared to group B's 198.50 minutes (p<0.001). Intrathecal nalbuphine did not influence vital indicators such as heart rate, respiration rate, and oxygen saturation.

Conclusion

To conclude, endoscopic urological surgery patients who received a subarachnoid block with 1.5 mg (0.15 ml) of nalbuphine hydrochloride with 0.5% hyperbaric bupivacaine 15 mg (3 ml) had longer postoperative pain relief than those who received 3 ml of intrathecal bupivacaine (15 mg). Urinary retention and pruritus were absent. Intrathecal nalbuphine with hyperbaric 0.5% bupivacaine is deemed safe with minimal side effects in endoscopic urology surgery.