Abstract:Abstract Objective: The study aimed to observe the analgesic effect of nalbuphine and dexmedetomidine, which as adjuvant of ropivacaine on local infiltration of incision after breast cancer surgery. Methods: Forty-six female patients underwent modified radical mastectomy of breast cancer were randomly divided into two groups: ND group (20 ml: dexmedetomidine 1μg/kg + nalbuphine 10 mg + 0.375% ropivacaine) and C group (20 ml 0.375% ropivacaine). The activity NRS (numerical rating scale) pain score and Ramsay sedation score were observed at 2 hours, 4 hours, 8 hours, 12 hours, 24 hours after surgery. Both consumption of remedial analgesics (morphine) and adverse reactions such as nausea and vomiting, bradycardia, hypotension and wound infection in 24 hours after surgery were recorded. Results: Morphine consumption in 24 hours and the movement NRS scores at 2 hours, 4 hours, 8 hours, 12 hours and 24 hours after surgery were significantly lower in ND group (P < 0.05); Ramsay scores in ND group at 2 hours, 4 hours and 8 hours after surgery were significantly higher in ND group (P < 0.05). But, there were no statistical differences in Ramsay sedation score between the two groups at 12 and 24 hours after surgery. There were also no significant differences in adverse reactions between the two groups. Conclusion: Nalbuphine combined with dexmedetomidine as adjuvant of ropivacaine for local infiltration of incision after breast cancer surgery can effectively improve the limitation in postoperative analgesia only with ropivacaine. As well reduce the use of opioids after surgery with fewer adverse effects. This method can provide more effective postoperative analgesia and comfort for patients.