Effect of Lidocaine on Postoperative Pain and Long-term Survival in Elderly Patients Undergoing Colorectal Surgery

Patients in the lidocaine group, lidocaine 1.5mg/kg/h is continuously infused (using ideal body weight) during the whole procedure, postoperative analgesia pump with lidocaine (lidocaine 50mg/kg, sufentanil 2ug/kg, glassetron 12mg) diluted to 200ml with saline until 72h after surgery.

In the placebo group, the same volume of normal saline will be administered during anesthesia. The postoperative PCIA device will contain sufentanil 2μg/kg, granisetron 12mg diluted to 200 mL in 0.9% normal saline solution with a total volume of 200 mL.