Objective: To observe respiration, circulation, and safety in patients with upper limb fracture receiving anesthesia with dexmedetomidine and brachial plexus block (BPB) during surgery. Methods: A total of 60 patients with upper limb fracture who were admitted to the hospital from January 2023 to December 2024 were selected, and divided into two groups using the stratified sampling method. The control group was anesthetized with ropivacaine combined with BPB, while the observation group was anesthetized with dexmedetomidine combined with BPB. Comparisons were made between the two groups on intraoperative respiration and circulation, anesthetic effect, 2-hour postoperative Visual Analogue Scale (VAS) score, and the incidence of postoperative adverse reactions. Results: Blood oxygen saturation in the observation group was higher than that in the control group at 10 min after anesthesia (T1) and 30 min after surgery (T2) (P<0.05). Compared with the control group, the observation group had lower heart rate at T1 and at the end of surgery (T3), and had higher heart rate at T2 (P<0.05). The onset time of sensory and motor block was shorter, and the duration was longer in the observation group (P<0.05). VAS score of the observation group was lower at 2 h postoperatively (P<0.05). The incidence of adverse reactions was comparable between the two groups (P>0.05). Conclusion: Using dexmedetomidine combined with BPB for anesthesia can maintain stable respiration and circulation in patients with upper limb fracture during surgery, enhance anesthetic effect, and prolong the duration of sensory block, with high safety.