Effects of Different Doses of Butorphanol on Perioperative Analgesia, Recovery, and Immune Function in Patients Undergoing Cytoreductive Surgery for Ovarian Cancer: A Randomized Controlled Trial

Guizhi Wang,1 Mengmeng Xu,2 Chuanyao Li,2 Na Zhang,2 Tingting Tian,2 Chen Gao,2 Wei Zhang1,2 1Graduate School, Bengbu Medical University, Bengbu, Anhui, People’s Republic of China; 2Department of Anesthesiology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, People’s Republic of ChinaCorrespondence: Wei Zhang, Graduate School, Bengbu Medical University, 2600 Donghai Avenue, Bengbu, Anhui, 233030, People’s Republic of China, Email [email protected] Chen Gao, Department of Anesthesiology, The First Affiliated Hospital of University of Science and Technology of China, No. 17 Lujiang Road, Luyang District, Hefei, 230001, People’s Republic of China, Email [email protected]: To investigate the optimal dose of butorphanol for patient-controlled intravenous analgesia (PCIA) by evaluating its effects on perioperative pain control and immune function in patients undergoing ovarian cancer surgery.Patients and Methods: Patients undergoing ovarian cancer surgery between May 2023 and March 2025 were randomized into four PCIA groups: Group S (sufentanil 0.04 μg·kg− 1·h− 1), B1 (low-dose butorphanol 3.0 μg·kg− 1·h− 1), B2 (medium-dose butorphanol 3.5 μg·kg− 1·h− 1), and B3 (high-dose butorphanol 4.0 μg·kg− 1·h− 1). Postoperative pain visual analog scale scores (VAS) were recorded for each group at T1 (2 h), T2 (6 h), T3 (12 h), T4 (24 h), and T5 (48 h). The number of PCIA button presses, rescue analgesia frequency, adverse reactions, inflammatory biomarkers, postoperative recovery indicators, and the level of lymphocyte subsets and NK cells were recorded.Results: VAS score at T3 was lower in group B3 than in S (P = 0.042). VAS scores at T3 and T4 were lower in groups B2 (P = 0.007 and P < 0.001) and B3 (P = 0.005 and P < 0.001) than in B1. Compared to group S, B1 showed an increased area under the curve of VAS time (AUCVAS-time) over 48 hours (P = 0.010), whereas group B3 exhibited a decrease in AUCVAS-time (P = 0.004). Group B3 had shorter postoperative time to ambulate than group S (P = 0.041). In group S, NK cells at T5 were lower than those at T0 (P = 0.007). In group B1, levels of CD4+ T cells, and CD4+/CD8+ ratio were higher at T5 than at T0 (P = 0.007 and P = 0.014), whereas CD8+ T cell count was lower (P = 0.011).Conclusion: High-dose butorphanol PCIA effectively relieves postoperative pain and reduces time to early ambulation without affecting immune indicators within 48 h postoperatively.Keywords: butorphanol, postoperative analgesia, cytoreductive surgery, immune function