Comparison of Ultrasound-guided interscalene block vs. analgosedation for shoulder reduction in a Swiss University Emergency Department

Purpose: Patients presenting with traumatic shoulder dislocation in the Emergency Department (ED), often get procedural sedation for shoulder reduction. Recent studies report the possibility of Ultrasound-guided interscalene block (US-ISB) in the ED, done by Emergency physicians (EP), to facilitate reduction without analgosedation. The aim of this study was to compare US-ISB vs. procedural sedation for shoulder reduction especially considering patient safety and length of stay in the ED.

Material and methods: We included adult out-patients with traumatic shoulder dislocation, two part fracture-dislocation (greater tuberosity), or dislocated shoulder prosthesis. Exclusion criteria for US-ISB were refusal by the patient, associated brachial plexus or axillary nerve palsy, infection at the injection site, or allergies to local anesthetics (LA). Ultrasound-guided single-shot LA was placed beneath the epineural sheath of the three trunks of the brachial plexus. US-ISB were performed by two EP and one emergency fellow resident who are trained in the technique. In the US-ISB group no further analgesics or sedatives were given. Reduction maneuvers were done by emergency fellow residents. The time of ED-entry and post-reduction radiograph has been taken as start- and endpoint.

Results: From January 2014 to March 2016 we included 145 out-patients (34 females, 111 males), median age 36.2 years (min. 17.0, max. 94.8). Underlying pathologies: dislocations 126 (86.9%), fracture-dislocations 17 (11.8%), and two dislocated shoulder prosthesis (1.4%). Depending on the availability of the three trained interventionists, US-ISB (30) or procedural sedation (115) has been done. The time between ED-entry and post-reduction X-ray was significant shorter in the US-ISB-group (mv 94 min) vs. sedation-group (mv 106 min), using the independent samples t-test. Complications (intravascular injections, neural lesions, later infections) were not seen in the US-ISB-group.

Conclusion: US-ISB for shoulder redution in the ED is a safe and effective method. Teaching priority for EP's should therefore focus on this technique.