Epidural nalbuphine versus dexmedetomidine as adjuvants to bupivacaine in lower limb orthopedic surgeries for postoperative analgesia: a randomized controlled trial.

Approval from the research ethics committee of the Faculty of Medicine, Zagazig University was obtained with the reference number (ZU-IRB#:7045-15-8-2021) and it was registered under clinicaltrials.gov (NCT05041270) on registration date 13/09/2021.