Modified clavipectoral block reduces pain and hemidiaphragmatic paralysis in clavicular surgery

BACKGROUND This study evaluated the efficacy and safety of modified clavipectoral fascial plane block (mCPB) plus superficial cervical plexus block (SCPB) compared with interscalene brachial plexus block (ISBP) in midshaft clavicular fracture surgery. MATERIAL AND METHODS Fifty-six patients scheduled for midshaft clavicular surgery under regional anesthesia were randomly allocated to a control (ultrasound-guided ISBP plus SCPB) or experimental (mCPB plus SCPB) group at a 1: 1 ratio. The primary outcome was the Numerical Rating Scale (NRS) score at 12 hours postoperatively. Secondary outcomes were NRS scores at 4, 8, and 24 hours; rescue analgesic administration frequency; block success rate; procedural and onset times; and hemidiaphragmatic paralysis incidence. RESULTS Block success was 100% in both groups, without differences in performance time or onset time. A significant group × time interaction was observed (P<0.001). Compared with the control group, the experimental group had significantly lower NRS scores at 12 hours (estimated mean difference -1.29; P<0.001) and 24 hours (estimated mean difference -2.36; P<0.001). No significant differences occurred at 4 or 8 hours. Rescue analgesic requirements within 24 hours were significantly reduced in the experimental group (P=0.002). Hemidiaphragmatic paralysis incidences were 71.4% in the control group and 0% in the experimental group (P<0.001). CONCLUSIONS In midshaft clavicular fracture surgery, mCPB plus SCPB provided effective anesthesia with procedural characteristics comparable to ISBP, while avoiding hemidiaphragmatic paralysis and demonstrating superior analgesia at 12 and 24 hours. These findings require validation in larger multicenter trials.