Comparative study of intra-articular lidocaine and intravenous meperidine/diazepam for shoulder dislocations.

The purpose of this study was to compare the analgesic effectiveness of intra-articular lidocaine versus intravenous meperidine and diazepam during the reduction of anterior shoulder dislocations. Patients were randomized to one of the two methods before the reduction of shoulder dislocations. Patients marked a visual analog pain scale at baseline, after anesthesia just before reduction, and at the time of discharge. Interference with the procedure caused by pain or lack of muscle relaxation, perception of adequacy of analgesia by the patient, adverse effects, and time to discharge from the Emergency Department (ED) were measured. Differences of outcomes, relative risks (RR), and 95% confidence intervals (CIs) were derived. Fifty-four patients with anterior shoulder dislocations presenting from May 21, 1998 through January 21, 1999 were included in this study; 29 were randomly assigned to receive intra-articular lidocaine (IAL) and 25 to receive intravenous meperidine/diazepam (IVMD). IAL was less effective than IVMD in relieving pre-reduction pain (p = 0.045) but equally effective in overall pain relief (p = 0.98). IAL was more effective than IVMD in shortening recovery time (p = 0.025). There was an indication favoring IVMD in terms of physician-perceived muscle relaxation and patient's perception of analgesia adequacy. In conclusion, although the IVMD method appears to have some clinically and statistically significant advantages, IAL possesses some favorable features that render it to be an analgesia alternative in shoulder dislocation reduction.