Document Detail

Ultrasound reduces the minimum effective local anaesthetic volume compared with peripheral nerve stimulation for interscalene block.
MedLine Citation:
PMID:  21059701     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Previous studies have demonstrated that lower local anaesthetic (LA) volumes can be used for ultrasound (US)-guided interscalene brachial plexus block (ISB). However, no study has examined whether US can reduce the volume required when compared with nerve stimulation (NS) for ISB. Our aim was to do this by comparing the minimum effective analgesic volumes (MEAVs).
METHODS: After ethics approval and informed consent, patients undergoing shoulder surgery were recruited to this randomized, double-blind, up-down sequential allocation study. The volume used for both US and NS was dependent upon the success or failure of the previous block. Success was defined as a verbal rating score of 0/10, 30 min after surgery. Ten needle passes were allowed before defaulting to the opposite group. Patients received general anaesthesia. Pain scores and analgesic consumption were assessed by a blinded observer. Statistical comparisons of continuous variables were performed using Student's t-test and Mann-Whitney U-test as appropriate. Categorical variables were analysed using χ² test. MEAV values were estimated using log-transformed up-down independent pairs analysis and probit regression. Significance was assumed at P<0.05 (two-sided).
RESULTS: The MEAV required to provide effective analgesia was significantly (P=0.034) reduced to 0.9 ml [95% confidence interval (CI) 0.3-2.8] in the US group from 5.4 ml (95% CI 3.4-8.6) in the NS group. Fewer needle passes were needed to identify the brachial plexus with US (1 vs 3; P<0.0001) and patients had less pain at 30 min after surgery (P=0.03).
CONCLUSIONS: US reduces the number of attempts, LA volume, and postoperative pain when compared with NS for ISB.
A McNaught; U Shastri; N Carmichael; I T Awad; M Columb; J Cheung; R M Holtby; C J L McCartney
Publication Detail:
Type:  Comparative Study; Journal Article; Randomized Controlled Trial; Research Support, Non-U.S. Gov't     Date:  2010-11-08
Journal Detail:
Title:  British journal of anaesthesia     Volume:  106     ISSN:  1471-6771     ISO Abbreviation:  Br J Anaesth     Publication Date:  2011 Jan 
Date Detail:
Created Date:  2010-12-14     Completed Date:  2011-01-18     Revised Date:  2011-08-08    
Medline Journal Info:
Nlm Unique ID:  0372541     Medline TA:  Br J Anaesth     Country:  England    
Other Details:
Languages:  eng     Pagination:  124-30     Citation Subset:  IM    
Department of Anaesthesia, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Anesthetics, Local / administration & dosage*
Brachial Plexus / anatomy & histology,  physiology,  ultrasonography
Double-Blind Method
Drug Administration Schedule
Electric Stimulation / methods
Fentanyl / administration & dosage
Middle Aged
Nerve Block / methods*
Pain Measurement / methods
Shoulder Joint / surgery
Ultrasonography, Interventional / methods
Reg. No./Substance:
0/Anesthetics, Local; 437-38-7/Fentanyl
Comment In:
Br J Anaesth. 2011 Jul;107(1):103; author reply 103-4   [PMID:  21685116 ]
Br J Anaesth. 2011 Apr;106(4):600; author reply 601-2   [PMID:  21421606 ]
Br J Anaesth. 2011 Apr;106(4):600-1; author reply 601-2   [PMID:  21421607 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  An update on the use of indacaterol in patients with COPD.
Next Document:  Exploring patients' self-reported experiences of out-of-hours primary care and their suggestions for...