Efficacy of Intravenous Lidocaine on Postoperative Pain and Recovery in Patients Undergoing Hepatectomy

Patients who meet the enrollment criteria will be randomized 1:1 to either the lidocaine or the placebo group.

In the lidocaine group, at the end of the induction of general anesthesia, a bolus injection of lidocaine 1.5 mg/kg, calculated using the patient's ideal body weight and given as an infusion over 10 minutes, followed by a continuous infusion of lidocaine at 1.5 mg/kg per hour for the whole surgical procedure and will be discontinued at the end of surgery.

Blood samples will be drawn immediately after the bolus infusion of lidocaine, at the end of the surgery, and 24 hours after surgery to measure plasma lidocaine concentrations. Blood samples will also be collected 24 hours after surgery for subsequent measurement of IL-6, and tumor necrosis factor-α (TNF-α). The obtained samples will be labeled, centrifuged, frozen, and stored locally at -80° for subsequent testing.

Postoperative pain management during the first 72 postoperative hours will involve the use of a PCIA device, which will contain lidocaine 30mg/kg, sufentanil 2 μg/kg, granisetron 12 mg diluted to 200 mL in 0.9 % normal saline. In the placebo group, the same volume of normal saline will be administered during anesthesia. The postoperative PCIA device will contain sufentanil 2 μg/kg, granisetron 12 mg diluted to 200 mL in 0.9% normal saline solution with a total volume of 200 ml. All the background infusions of PCIA will set at 2 ml/h, the bolus volume of each PCIA press is 2 ml and the lockout interval is 15 min.

Inclusion criteria

• Age: 18-80 years old
• American Society of Anesthesiologists(ASA) Ⅰ～III
• patients scheduled for elective hepatectomy

Exclusion criteria

• body weight < 40 kg or >100 kg; metastases occurring in other distant organs; severe hepatic insufficiency (aspartate aminotransferase or alanine transaminase or bilirubin > 2.5 times the upper limit of normal), renal impairment (creatinine clearance < 60 ml/min); cardiac rhythm disorders or systolic heart failure (second-and third-degree heart block, ejection fraction < 50%); with allergies to any of the trial drugs; inability to comprehend numeric rating scale.