Clinical trial NCT01244932: Minimum Effective Volume of Local Anesthetic Using Ultrasound for Brachial Plexus Block
Official title: Determination of the Minimum Effective Volume of Local Anesthetic Using Ultrasound Guidance for Interscalene Brachial Plexus Block
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
Conditions: Anesthesia
Lead sponsor: Federal University of São Paulo
Sponsor class: OTHER
First posted: 2010-11-22
Enrollment: 33
Sex: ALL
Minimum age (years): 21
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to determine the minimum effective volume of local anesthetic for interscalene brachial plexus block using ultrasound guidance and nerve stimulator guidance.

Detailed description: This will be a single group assignment, double-blind, up-down sequential allocation study. Interscalene brachial plexus block (ISBPB) is a common nerve block given to patients who are undergoing shoulder surgery. This block has a low, but still significant, rate of complications. Reducing the volume of local anesthetic given during the block may allow some of these complications to be avoided. Participants will undergo ISBPB under ultrasound and nerve stimulator guidance. Patients will initially receive 15mL of local anesthetic (bupivacaine 0.5% with epinephrine). The volume used for each subsequent patient depends upon the success or failure of the previous patient's block - a failure will cause the volume given to increase by 1.0 mL, while a success will cause the volume to decrease by the same amount.

The goal of this study is to determine the minimum effective anesthetic volume of bupivacaine 0.5% providing anesthesia in patients when using ultrasound and nerve stimulator to guide placement of the block. The secondary outcome will be the evaluation of diaphragmatic function and post-surgery analgesia.

Eligibility criteria: Inclusion Criteria:

* Patients receiving interscalene brachial plexus block for shoulder surgery
* Age between 21 and 65 years
* ASA physical status I/II
* Body mass index \< 35 kg/m2

Exclusion Criteria:

* Chronic obstructive pulmonary disease
* Psychiatric history
* Allergy to bupivacaine
* Infection in the site of block
* Coagulation disorders

Primary outcomes:
measure: ED95 of bupivacaine minimum effective volume
timeFrame: ED95
Secondary outcomes:
measure: Diaphragmatic Function
timeFrame: Diaphragmatic
measure: Post-surgery analgesia
timeFrame: Analgesia
Other outcomes:
Locations:
city: Sao Paulo
country: Brazil
facility: Luiz Fernando dos Reis Falcao
state: SP
Study officials:
affiliation: Federal University of São Paulo
name: Luiz Fernando Falcao, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Farquhar-Thomson DR, Baker AK, Satapathy AR, Coventry D, Harper GK, Stafford MA, Hill DA. Minimum volume of local anaesthetic required for an axillary brachial plexus block. Br J Anaesth. 2010 Sep;105(3):382-3. doi: 10.1093/bja/aeq220. No abstract available.
citation: Ponrouch M, Bouic N, Bringuier S, Biboulet P, Choquet O, Kassim M, Bernard N, Capdevila X. Estimation and pharmacodynamic consequences of the minimum effective anesthetic volumes for median and ulnar nerve blocks: a randomized, double-blind, controlled comparison between ultrasound and nerve stimulation guidance. Anesth Analg. 2010 Oct;111(4):1059-64. doi: 10.1213/ANE.0b013e3181eb6372. Epub 2010 Aug 12.
citation: Harper GK, Stafford MA, Hill DA. Minimum volume of local anaesthetic required to surround each of the constituent nerves of the axillary brachial plexus, using ultrasound guidance: a pilot study. Br J Anaesth. 2010 May;104(5):633-6. doi: 10.1093/bja/aeq050. Epub 2010 Mar 16.
citation: Duggan E, El Beheiry H, Perlas A, Lupu M, Nuica A, Chan VW, Brull R. Minimum effective volume of local anesthetic for ultrasound-guided supraclavicular brachial plexus block. Reg Anesth Pain Med. 2009 May-Jun;34(3):215-8. doi: 10.1097/AAP.0b013e31819a9542.
citation: O'Donnell BD, Iohom G. An estimation of the minimum effective anesthetic volume of 2% lidocaine in ultrasound-guided axillary brachial plexus block. Anesthesiology. 2009 Jul;111(1):25-9. doi: 10.1097/ALN.0b013e3181a915c7.
citation: Gupta PK, Pace NL, Hopkins PM. Effect of body mass index on the ED50 volume of bupivacaine 0.5% for supraclavicular brachial plexus block. Br J Anaesth. 2010 Apr;104(4):490-5. doi: 10.1093/bja/aeq017. Epub 2010 Feb 18.
citation: Marhofer P, Eichenberger U, Stockli S, Huber G, Kapral S, Curatolo M, Kettner S. Ultrasonographic guided axillary plexus blocks with low volumes of local anaesthetics: a crossover volunteer study. Anaesthesia. 2010 Mar;65(3):266-71. doi: 10.1111/j.1365-2044.2010.06247.x. Epub 2010 Jan 29.
citation: Renes SH, Rettig HC, Gielen MJ, Wilder-Smith OH, van Geffen GJ. Ultrasound-guided low-dose interscalene brachial plexus block reduces the incidence of hemidiaphragmatic paresis. Reg Anesth Pain Med. 2009 Sep-Oct;34(5):498-502. doi: 10.1097/AAP.0b013e3181b49256.
citation: Smith HM, Duncan CM, Hebl JR. Clinical utility of low-volume ultrasound-guided interscalene blockade: contraindications reconsidered. J Ultrasound Med. 2009 Sep;28(9):1251-8. doi: 10.7863/jum.2009.28.9.1251.
citation: Falcao LF, Perez MV, de Castro I, Yamashita AM, Tardelli MA, Amaral JL. Minimum effective volume of 0.5% bupivacaine with epinephrine in ultrasound-guided interscalene brachial plexus block. Br J Anaesth. 2013 Mar;110(3):450-5. doi: 10.1093/bja/aes419. Epub 2012 Nov 29.