title: Single versus triple injection ultrasound-guided infraclavicular block: confirmation of the effectiveness of the single injection technique.
abstract: BACKGROUND
  The optimal site for local anesthetic placement during ultrasound-guided infraclavicular block remains controversial.
  
  
  METHODS
  Patients were randomized to receive lidocaine 2% 30 mL as a single injection posterior to the axillary artery (n = 51) or a triple injection ideally adjacent to each brachial plexus cord (n = 49). Pinprick sensory and motor block (3 = no block, 0 = complete block) were assessed to 20 minutes in the 4 distal nerve territories.
  
  
  RESULTS
  The single injection group was not significantly inferior (single versus triple injection median [interquartile range] 20-minute aggregate block score: 5 [2-9] vs 7 [3.5-11]) but also demonstrated superiority (2-tailed test, P = 0.043). The single injection technique was associated with a small reduction in procedural time.
  
  
  CONCLUSIONS
  The optimal site for local anesthetic placement during ultrasound-guided infraclavicular block is a single point injection posterior to the axillary artery.
authors: Department of Anaesthesiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand. michaelfredrickson@yahoo.com
authors: Michael J
authors: MJ
authors: Fredrickson
authors: Philip
authors: P
authors: Wolstencroft
authors: Ritwik
authors: R
authors: Kejriwal
authors: Albert
authors: A
authors: Yoon
authors: Michael R
authors: MR
authors: Boland
authors: Simon
authors: S
authors: Chinchanwala
mesh_terms: D000328:Adult; D000368:Aged; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001366:Axillary Artery / Q000000981:diagnostic imaging*; D001917:Brachial Plexus / Q000000981:diagnostic imaging* / Q000187:drug effects*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007267:Injections; D008012:Lidocaine / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000187:drug effects; D009407:Nerve Block / Q000379:methods*; D009520:New Zealand; D019637:Orthopedic Procedures; D012677:Sensation / Q000187:drug effects; D013997:Time Factors; D018084:Ultrasonography, Interventional
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine