Interscalene brachial plexus block for surgical repair of clavicle fracture: a matched case-controlled study

BACKGROUND: Innervation of the clavicle is complex and debated, with scarce data on the analgesic and clinical impact of regional anaesthesia after surgical repair of clavicle fracture. METHODS: In order to assess the analgesic efficiency of an interscalene brachial plexus block (ISB) for surgical repair of clavicle fracture, 50 consecutive patients scheduled for surgical fixation of middle/lateral clavicle fracture under general anaesthesia with ISB were prospectively enrolled. This cohort was compared to a historical control of 76 retrospective patients without regional block. The primary outcome was total intravenous morphine equivalent consumption at 2 postoperative hours. To assess the ISB impact, both an overall cohort analysis and a case-matched analysis with each ISB-treated patient matched to a Non-ISB-treated patient was performed. Matching employed a 1-to-1, nearest-neighbour approach using the Mahalanobis metric. RESULTS: In the overall cohort, patients with ISB had significantly lower i.v. morphine equivalent consumption at 2 postoperative hours (0.7 mg (95% CI 0.1 to 1.2) versus controls 8.8 mg (95% CI 7.1 to 10.4); P < 0.0001). These results persisted after case-matching the cohorts (mean difference for the primary outcome: 8.3 mg (95% CI 6.5 to 10.0); P < 0.001). CONCLUSIONS: ISB provides effective analgesia after surgical fixation of middle and lateral clavicle fracture. These results should help physicians in establishing an analgesic strategy for this type of surgery. Further research is needed to identify the optimal regional technique for medial third clavicle fractures and the clinically relevant contributions of the cervical and brachial plexus. TRIAL REGISTRATION: Clinicaltrials.gov – NCT02565342, October 1st 2015.