Anesthetic methods for reduction of acute shoulder dislocations: a prospective randomized study comparing intraarticular lidocaine with intravenous analgesia and sedation

Abstract

A prospective, randomized, nonblinded clinical trial was undertaken to evaluate whether local intraarticular lidocaine injection (IAL) is equally effective in facilitating reduction of acute anterior shoulder dislocations (AASD) as intravenous analgesia/sedation (IVAS). The setting was an urban, Level 1, trauma center. Patients enrolled presented to the emergency department (ED) with radiographically confirmed AASD and were randomized either to the IVAS group or the IAL group. Ease of reduction and pain associated with reduction were measured subjectively using a 10-point scale. There were 49 patients entered into the study, 20 in the IVAS group and 29 in the IAL group. There was no statistically significant difference between mean +/- SD pain scores of 3.32+/-2.39 in the IVAS group and 4.90+/-2.34 in the IAL group (P = .18), or mean +/- SD ease of reduction scores of 3.32+/-2.36 in the IVAS group and 4.45+/-2.46 in the IAL group (P = .12). Although IVAS tended to have a higher success rate (20 of 20) than IAL (25 of 29) in this study, Kaplan-Meier estimates for delayed time-events curves applying the log-rank test showed that this difference was not statistically significant overall (P = .16). However, with reduction rate evaluated as a function of time delay in seeking treatment, patients presenting 5.5 hours after dislocation were more likely to fail treatment with IAL (P = .00001). Additionally, half of the patients in the IAL group who had experience with IVAS did not favor IAL. Emergency physicians should be aware of IAL as an alternative technique that may be considered in patients when there are reasons to avoid systemic analgesia or sedation.