Effect of Liposomal Bupivacaine and Bupivacaine Hydrochloride for Superior Trunk Block of the Interscalene Brachial Plexus on Postoperative Diaphragmatic Function and Analgesia

Effect of Liposomal Bupivacaine and Bupivacaine Hydrochloride for Superior Trunk Block of the Interscalene Brachial Plexus on Postoperative Diaphragmatic Function and Analgesia in Shoulder Surgery: A Multicenter, Randomized Controlled Study

To compare the effects of 1.33% liposomal bupivacaine versus 0.375% bupivacaine hydrochloride for superior trunk block of the interscalene brachial plexus on postoperative diaphragmatic function and analgesic efficacy in shoulder surgery.

Inclusion Criteria:

• Patients scheduled for elective unilateral proximal humerus surgery, rotator cuff surgery, shoulder arthroplasty, or shoulder arthroscopy;
• Visible diaphragmatic movement on the surgical side under ultrasound before anesthesia;
• Patient provides informed consent;
• Age 18-80 years, any gender;
• ASA physical status I-III;
• 18 kg/m² ≤ BMI ≤ 30 kg/m².

Exclusion Criteria:

• Coagulopathy;
• Allergy to local anesthetics;
• Infection at the puncture site;
• History of chronic pain or opioid use;
• Severe respiratory disease;
• Pregnancy;
• Diabetes and peripheral neuropathy;
• Inability to understand assessment scales.