Intrathecal Nalbuphine Versus Other Opioids as Adjuvant to 0.5% Hyperbaric Bupivacaine in Caesarean Section: A Systematic Review and Meta-Analysis. - Theodorou-Kanakari, Anna; Karathanasi, Styliani; Lykoudis, Panagis M.; Rekatsina, Martina; Lelekaki, Eleftheria; Gavriilaki, Maria; Kouki, Pinelopi (Journal of Clinical Medicine, 2026)