Preperitoneal Infiltration

Upper abdominal open surgery is associated with significant trauma, and postoperative pain management poses considerable challenges. The inflammatory response triggered by peritoneal incision and the transmission of visceral pain via the vagus nerve are key components of "surgical stress" and pain. A potential intervention strategy involves the local administration of anesthetic agents to suppress peritoneal overreaction and block the cascade of pro-inflammatory cytokines in related nerves. Liposomal bupivacaine, as a long-acting local anesthetic, may provide more prolonged postoperative analgesia compared to ropivacaine. Therefore, this trial aims to prospectively compare the analgesic efficacy and anti-inflammatory effects of the two drugs when administered as pre-closure preperitoneal infiltration. Secondary endpoints include opioid consumption, complication rates, and postoperative recovery indicators, to comprehensively evaluate their clinical value.