1. Ultrasound reduces the minimum effective local anaesthetic volume compared with peripheral nerve stimulation for interscalene block 
A McNaught, U Shastri, N Carmichael, I.T. Awad, M Columb, J Cheung, R.M. Holtby, C.J.L. McCartney 
British Journal of Anaesthesia 
Volume 106, Issue 1, Pages (January 2011)
DOI: /bja/aeq306
Copyright © 2011 The Author(s) Terms and Conditions

2. Fig 1
Up–down sequence for both US and NS with dotted lines indicating 95% CIs.
British Journal of Anaesthesia  , DOI: ( /bja/aeq306)
Copyright © 2011 The Author(s) Terms and Conditions