Efficacy and Safety of Liposomal Bupivacaine and Ropivacaine in Upper Limb Surgery

Anesthesia induction will be achieved using propofol (1.5-2 mg/kg i.v.), rocuronium (1-2 mg/kg i.v.), and fentanyl (1-2 μg/kg i.v.). Anesthesia will be maintained using sevoflurane or desflurane, with inhaled concentration adjusted based on Bispectral Index (BIS) monitoring. A continuous infusion of remifentanil (0.05-0.2 μg/kg/min) will be administered, with adjustments to maintain blood pressure and heart rate within ±20% of baseline values. Following induction, patients will be mechanically ventilated in pressure-regulated volume control (PRVC) mode. The ventilator (Aestiva; GE Healthcare, Waukesha, Wisconsin, USA) settings will be: tidal volume 6-8 mL/kg, positive end-expiratory pressure 0 cm H2O, inspiratory to expiratory ratio 1:2, respiratory rate 16 breaths per minute (BPM), and fraction of inspired oxygen 41%.

Patients were positioned supine with the head slightly turned to the contralateral side to expose the supraclavicular fossa. The injection site was prepared using standard aseptic techniques. Under ultrasound guidance, a needle was advanced to the vicinity of the brachial plexus. Aspiration was performed to confirm the absence of blood return before the slow, incremental injection of either liposomal bupivacaine \[adult dose: 133 mg (10 mL) to 266 mg (20 mL)\] or ropivacaine \[adult dose: 20 mL of 0.5% ropivacaine, administered via continuous infusion at a rate of 5-10 mL/h; pediatric dose: 0.1% ropivacaine at 0.1-0.2 mL/kg, administered via continuous infusion at 0.05-0.15 mL/kg/h\]. Patient responses were closely monitored throughout the procedure.