Determination of the Optimal Volume of Liposomal Bupivacaine in Adductor Canal Block for Knee Joint Surgery

Determination of the Optimal Volume of Liposomal Bupivacaine in Single-Shot Adductor Canal Block for Knee Joint Surgery-A Phase I/II Trial

Building on Bayesian design methodologies from volume optimization studies of ropivacaine in shoulder surgery, this study pioneers the application of a seamless dose-finding strategy in knee ACB. Utilizing advanced statistical models (BOIN/BOP2 design), we aim to systematically evaluate the volume-effect relationship of liposomal bupivacaine, providing precise dosing recommendations to advance personalized and optimized analgesic protocols for knee surgery.

Inclusion Criteria:

• Patients undergoing elective general anesthesia for unilateral knee joint surgery.
• Patients who provide informed consent.
• Aged between 18 and 65 years old, regardless of gender.
• American Society of Anesthesiologists (ASA) physical status classification of Ⅰ to Ⅲ
• Body mass index (BMI) ≤ 35 kg/m².

Exclusion Criteria:

• Femoral neuropathy.
• Coagulation dysfunction.
• Allergy to local anesthetics.
• Infection at the puncture site.
• History of chronic pain or opioid use.
• Pregnancy.
• Diabetes mellitus and peripheral neuropathy.