Comparison of ultrasound-guided interscalene block versus procedural sedation for closed shoulder reduction in a swiss university emergency department

Background: To facilitate shoulder reduction and shorten time from shoulder dislocation to reduction, we started in 2014 a protocol for ultrasound-guided interscalene block (UGIB) in pure shoulder dislocation as well as dislocation with greater tuberosity fracture and dislocated shoulder arthroplasty. Methods: Within 30 month, patients with shoulder dislocation, dislocation-fracture or dislocated arthroplasty were enrolled for UGIB. Exclusion criteria were sensomotoric deficits, compromised circulation, and refusal by patient or surgeon, infection at the injection site or allergy to local anesthetics. A linear ultrasound probe was used to visualize injection of 9ml local anesthetics into the interscalene groove. In case of unavailability of an UGIB-trained interventionist, reduction was done under procedural sedation. Time between admission and post-reduction x-ray was registered. UGIBand sedation-groups were compared. Results: We encountered 168 patients (m 124, f 44) with shoulder dislocation (147), dislocation-fracture (19) or dislocated shoulder arthroplasty (2). Forty five patients (mean age 54.4y; min 17.7; max 94.8) matched UGIB-criteria; 123 patients (mean age 43.7y; min 17.0; max 88.1) received procedural sedation. Time from admission to post reduction x-ray in the UGIB-group (MV 83min±62.4) was significantly shorter than in the PS-group (MV 129min±112.7). No block-related complications occurred. We got follow-up information from 42 UGIB-patients: 35 patients would opt again for UGIB, whereas 2 patients experienced the procedure as uncomfortable, 3old patients could not remember and 2 were deceased meanwhile. Conclusions: UGIB is a reliable, fast method for shoulder reduction in shoulder dislocation, dislocationfracture and dislocated shoulder arthroplasty. Patients benefit from the shortening between shoulder dislocation and reduction.