Interscalene Block Versus Pericapsular Nerve Block and Superficial Cervical Plexus Block for Arthroscopic Shoulder...

Interscalene brachial plexus block (ISB) remains the gold standard for analgesia in arthroscopic shoulder surgery (ASS). However, ISB is associated with a higher incidence of hemidiaphragmatic paralysis (DP).

This study compares ultrasound-guided interscalene brachial plexus block (USG-ISB) with a combination of ultrasound-guided pericapsular nerve block (USG-PENB) and superficial cervical plexus block (SCPB) to evaluate analgesic efficacy and the incidence of DP.

In this prospective, triple-blinded randomized trial, 42 American Society of Anesthesiologists (ASA) I - II patients undergoing elective ASS were randomized into two groups after induction of general anesthesia (GA): Group A (ISB, 10 mL 0.25% bupivacaine) or group B [pericapsular nerve block (PENB) 10 mL + SCPB 5 mL 0.25% bupivacaine]. Blocks were performed under ultrasound guidance. The primary outcome was the incidence of DP; secondary outcomes included pain scores, opioid consumption, pulmonary function, and patient satisfaction.

Compared with group A, group B demonstrated a delayed time to first request for rescue analgesia (13.24 vs. 8.38 hours; P < 0.001) and reduced 24-hour fentanyl consumption (135.71 vs. 192.86 mcg; P = 0.012). Pulmonary function was significantly better preserved in group B (P < 0.05). The incidence of DP was lower in group B (4.76% vs. 38.1%; P = 0.02). Pain scores at 6, 12, and 18 hours were also lower in group B (P < 0.05). Both groups showed no differences in hypotension, bradycardia, or patient satisfaction.

The combination of PENB and SCPB provides analgesia non-inferior to ISB, while significantly reducing the incidence of DP and opioid requirements. For individuals at risk of respiratory impairment, this approach presents a lower-risk alternative without compromising pain control efficacy.