Comparison between intrathecal nalbuphine and butorphanol as adjuvants to isobaric ropivacaine in elective lower limb orthopedic surgeries: A prospective, randomized, double blind study

Abstract

Background: Intrathecal ropivacaine is now routinely used for lower limb surgery. Adjuvants e.g. fentanyl, dexmedetomidine or morphine etc. are commonly used to prolong the intraoperative anesthesia or postoperative analgesia. The available literature lacks information on use of butorphanol and nalbuphine as adjuvants with 0.75% isobaric ropivacaine. We aimed to compare nalbuphine and butorphanol as adjuvant with isobaric ropivacaine in lower limb orthopedic surgeries.

Methodology: After institutional ethical committee approval and informed written consent, a total of 108 patients of ages between 18 to 65 y, of either sex, American Society of Anesthesiologists (ASA) grade ӏ & ӏӏ, scheduled for elective lower limb orthopedic surgeries, were enrolled and  randomly allocated into two groups: Group RN; to receive isobaric ropivacaine (0.75%, 7.5 mg/ml) 2.5 ml plus nalbuphine 500 µg (0.5 ml), and Group RB; to receive isobaric ropivacaine 2.5 ml plus butorphanol 100 µg (0.5 ml) intrathecally. Primary outcome measure was the duration of sensory‑motor blockade from the time of intrathecal drug administration. Statistical analysis was performed by using t-test and chi-square test as applicable. A p < 0.05 was considered as significant.

Results: Duration of sensory (p < 0.001) and motor blockade (p = 0.02) was significantly prolonged in nalbuphine group than butorphanol group. Onset of blockade was earlier in nalbuphine group. Duration of motor block and sensory analgesia was prolonged in group RN (p < 0.001). Perioperative hemodynamic parameters and the observed side effects including bradycardia, hypotension, nausea and vomiting, sedation and shivering were comparable between the two groups (p = 0.77).

Conclusion: Intrathecal nalbuphine produces prolonged motor blockade as well as postoperative analgesia than intrathecal butorphanol when used as adjuvants to isobaric 0.75% ropivacaine.

Citation: Nirmal A, Singh Y, Mathur SK, Patel S. Comparison between intrathecal nalbuphine and butorphanol as adjuvants to isobaric ropivacaine in elective lower limb orthopedic surgeries: A prospective, randomized, double blind study. Anaesth pain & intensive care 2019;23(4)__

Received: 22 August 2019; Reviewed: 8, 9 October 2019; 6, 7 November 2019; Revised: 18 November 2019; Reviewed: 19 November 2019; Accepted: 20 November 2019