Observation on analgesic effects of ropivacaine sciatic nerve block guided by ultrasound combined with a nerve stimulator after fracture of the calcaneus

Background: Calcaneal fracture (FOC) is a common foot trauma. Severe postoperative pain can easily trigger the body's stress response, increase the risk of thrombosis, and seriously affect the recovery of patients. Sciatic nerve block (SNB) guided by traditional nerve stimulator (NS) has some problems such as inaccurate positioning and unstable block effect. Ultrasound-guided technology can visualize the nerve structure and puncture process in real time to improve the accuracy of block. Objective: In this study, we observed the analgesic effect of ropivacaine SNB on FOC under the guidance of ultrasound combined with a NS. Methods: We retrospectively analyzed 200 FOC patients, including 113 patients who received ropivacaine SNB guided by ultrasound combined with an NS (ultrasound group) and 87 patients who received ropivacaine SNB under the guidance of an NS (conventional group). Results: The ultrasound group showed a shorter onset time of anesthesia and a greater number of grade I (the block was successful and the patient had no obvious pain and muscle relaxation) anesthetic effect in patients (P<0.05). At 30 minutes after analgesia and 60 minutes after analgesia, the vital signs of the ultrasound group were more stable. In addition, the stress response indexes Epinephrine (E) and Cortisol (Cor) in the Ultrasound group were lower than those in the conventional group (P<0.05) and coagulation function indexes were higher than those in the conventional group (P<0.05). Finally, the incidence of adverse reactions in the ultrasound group was lower than that in the conventional group (10.34% vs. 2.65%, P<0.05). Conclusion: Ultrasound-guided ropivacaine SNB combined with NS has a good analgesic effect in analgesia after FOC surgery.