Ultrasound Guidance With Nerve Stimulation Reduces the Time Necessary for Resident Peripheral Nerve Blockade Steven L. Orebaugh, M.D., Brian A. Williams, M.D., M.B.A., and Michael L. Kentor, M.D. Background and Objectives: Educating residents in peripheral nerve blockade may impact the efficiency of a busy regional anesthesia service. Ultrasound guidance may affect the efficiency and effectiveness of nerve block. We examined the impact of ultrasound guidance on resident performance of peripheral nerve block in a regional anesthesia rotation. Methods: An existing de-identified database was used for retrospective analysis of resident performance of interscalene, axillary, femoral, and popliteal nerve blocks, by peripheral nerve stimulator guidance alone and by nerve stimulator aided by ultrasound. The primary variable examined was the time required to perform the block. Others variables included (1) number of needle insertions; (2) proportion of blocks in which there was a blood vessel puncture; and (3) block efficacy. Peripheral nerve-stimulator blocks were guided by surface anatomy and motor stimulation, refined to 0.2 to 0.5 mA of current before injection of local anesthetic, while ultrasound nerve stimulator blocks were confirmed using a current of 0.5 mA. Results: Ultrasound-aided blocks required less time to perform (median = 1.8 min) than nerve stimulator- guided blocks (median = 6.5 min, P  .001). More needle insertions were required for nerve localization in the nerve stimulator-guided blocks (median = 6) than in ultrasound-aided blocks (median = 2; P  .001). There were fewer blood vessel punctures with ultrasound-aided blocks (P = .03). Conclusions: During resident teaching, ultrasound-aided peripheral nerve-stimulated block required less time to perform than did nerve-stimulator-guided blocks. Fewer needle insertions were required to perform the ultrasound-guided blocks, and there were fewer blood vessel punctures when ultrasound was used. Reg Anesth Pain Med 2007;32:448-454. Key Words: Ultrasound, Nerve block, Education, Resident. T eaching regional anesthesia is challenging. Along with customary concerns about patient-related complications, teaching physicians must be concerned with both patient discomfort and the impact of teach- ing on a busy surgical schedule. Education of resi- dents, in particular, may increase the time required to complete a regional block, or decrease the likelihood of block success, with a potentially adverse effect on a busy anesthetic service. Konrad et al. evaluated the “learning curve” for several skills in anesthesia, and found that residents attained a success rate with axil- lary block of only 70% after performance of 20 pro- cedures. 1 Real-time ultrasound (US) guidance may allow for more efficient nerve block, by making the target nerve and needle apparent. In some studies, periph- eral blocks have shown more rapid onset when US is used to guide local anesthetic delivery, and less local anesthetic may be necessary to complete an effective block. 2,3 Recent trends suggest that this technology will become an indispensable part of regional anesthesia practice. 4 Comparison of resi- dent performance of peripheral nerve block (PNB) by nerve stimulator (NS) guidance alone with that of blocks guided by both NS and US has not been reported. The primary aim of this retrospective study, uti- lizing a de-identified database, was to determine whether supervised anesthesiology residents were able to conduct peripheral nerve blocks as rapidly From the Department of Anesthesiology, UPMC-Southside, University of Pittsburgh School of Medicine, Pittsburgh, PA. Accepted for publication May 11, 2007. Support for this investigation was strictly from departmental resources. Presented in part at the Annual Meeting of the Amer- ican Society for Regional Anesthesia and Pain Medicine, Rancho Mirage, CA, April 7, 2006. Reprint requests: Steven L. Orebaugh, M.D., Department of Anesthesiology, UPMC-Southside, 2000 Mary Street, Pittsburgh, PA 15203. E-mail: orebaughsl@anes.upmc.edu © 2007 by the American Society of Regional Anesthesia and Pain Medicine. 1098-7339/07/3205-0014$32.00/0 doi:10.1016/j.rapm.2007.05.004 448 Regional Anesthesia and Pain Medicine, Vol 32, No 5 (September–October), 2007: pp 448 –454