Objective: To evaluate the effect of liposomal bupivacaine on postoperative analgesia in patients undergoing foot and ankle surgery under combined popliteal sciatic-saphenous nerve block. Methods: Eighty-eight patients, 50 males and 38 females, aged 18-80 years, BMI 18.5-30.0 kg/m 2, ASA physical status Ⅰ-Ⅲ, scheduled for open reduction and internal fixation of foot/ankle fractures were enrolled. Patients were randomized into two groups using a random number table: liposomal bupivacaine combined with bupivacaine (group LB) and dexamethasone combined with bupivacaine (group BD), 44 patients in each group. Group LB received liposomal bupivacaine 199.5 mg and bupivacaine 50 mg, while group BD received bupivacaine 112.5 mg and dexamethasone 6 mg, both diluted with normal saline to 30 ml. All patients underwent popliteal sciatic nerve block and saphenous nerve block, with 20 ml injected for the popliteal block and 10 ml for the saphenous block. Outcomes included time to first analgesic request, numerical rating scale (NRS) pain scores at rest and during activity (ankle dorsiflexion and plantar flexion) at 6, 12, 24, 48, and 72 hours postoperatively, and the area under the curve (AUC) for pain scores. Cumulative oxycodone consumption, total patient-controlled analgesia (PCA) button presses, and effective PCA button presses during the intervals of 0-12 hours, > 12-24 hours, > 24-48 hours, and > 48-72 hours postoperatively were recorded. The incidence of adverse effects, including nausea, vomiting, dizziness, somnolence, and pruritus was also recorded within 72 hours postoperatively. Results: Compared with group BD, group LB had a significantly prolonged time to first analgesic request (P < 0.05), significantly lower NRS pain scores at rest and during activity at 24 and 48 hours postoperatively (P < 0.05), as well as a significantly lower AUC for NRS pain scores at rest and during activity at 72 hours postoperatively (P < 0.05). The cumulative oxycodone consumption, total PCA button presses, and effective PCA button presses were significantly reduced during the intervals of > 24-48 hours and > 48-72 hours postoperatively (P < 0.05). There were no significant differences in the incidence of adverse effects, including nausea, vomiting, dizziness, somnolence, and pruritus, between the two groups. Conclusion: Bupivacaine liposome effectively prolongs the analgesic duration of bupivacaine in popliteal sciatic-saphenous nerve block, reduces postoperative pain, and decreases postoperative opioid consumption. |