Scalene regional anesthesia for shoulder surgery in a community setting: An assessment of risk

Background: A retrospective review of shoulder procedures using scalene block anesthesia was performed. Methods: The records of all 218 patients who had undergone scalene block anesthesia over a three-year period at two facilities were retrospectively reviewed. All blocks were performed with use of a standard blunt-needle technique with the patient awake and with use of preoperative nerve stimulation to localize the brachial plexus. Results: Adjunctive general anesthesia was used for 179 (82%) of the 218 patients. Seventy-two patients (33%) required intravenous pain medication immediately on arrival in the recovery room, and twenty-eight blocks (13%) failed. One grand mal seizure, one episode of cardiovascular collapse, and four episodes of severe respiratory distress were noted. Two patients had temporary neurologic injuries that persisted at six weeks. The mean duration of the block was 9 ± 4.6 hours. Two hundred (92%) of the 218 patients required parenteral narcotics despite the use of scalene block anesthesia. Conclusion: Informed consent discussions regarding scalene block anesthesia should include information on the prevalence of complications and the efficacy of the technique.