Evaluating Hemidiaphragmatic Paralysis With Prolonged Neural Blockade From an Interscalene Brachial Plexus Block

What this Trial Is About

Researchers are studying the occurrence of hemidiaphragmatic paralysis in patients undergoing shoulder surgery who receive an interscalene brachial plexus nerve block with prolonged neural blockade. This observational study includes English-speaking patients aged 18 to 80 with ASA physical status 1 to 3. Participants are divided into three groups to compare different nerve block methods. The main goal is to assess diaphragm paralysis on the first day after surgery using ultrasound imaging. Participants are assigned to one of three treatment groups: one receives a continuous infusion of 0.2% ropivacaine through a perineural catheter; the second group receives a single injection of 10 mL liposomal bupivacaine plus 5 mL of 0.5% bupivacaine; the third group receives a single injection of 20 mL liposomal bupivacaine plus 5 mL of 0.5% bupivacaine. The exact dosing for the third group is determined by the attending anesthesiologist. The study uses ultrasound to monitor diaphragm function and a non-invasive respiratory monitor to evaluate lung function. During the study, participants are monitored using point-of-care ultrasound immediately after surgery and on postoperative days 1, 2, and 3 to detect diaphragm paralysis. Researchers also measure pulmonary gas exchange, pain levels on a 0-10 scale, opioid use, and side effects like hoarseness and Horner's syndrome during this 72-hour period. The study continues until August 2026, with all evaluations focused on the first three days after surgery to understand the safety and effects of these nerve block techniques.

Evaluating Hemidiaphragmatic Paralysis With Prolonged Neural Blockade From an Interscalene Brachial Plexus Block