Minimum Effective Volume of 0.375% Bupivacaine in Interscalene Brachial Plexus Block

Shoulder Surgery Clinical Trial

Official title:

Minimum Effective Volume of 0.375% Bupivacaine in Ultrasound- and Nerve Stimulator-guided Interscalene Brachial Plexus Block for Shoulder Surgery

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT01667315
• Other study ID #: Bupivacaine 0,375%
• Status: Recruiting
• Phase: Phase 2
• First received: August 13, 2012
• Last updated: August 16, 2012
• Start date: August 2012
• Est. completion date: September 2013

Study information

• Verified date: August 2012
• Source: Federal University of São Paulo
• Contact: n/a
• Is FDA regulated: No
• Health authority: Brazil: Ethics Committee
• Study type: Interventional

Clinical Trial Summary

The use of ultrasound in regional anesthesia enables reduction in the local anesthetic volume. The present study aimed to determine the minimum effective volume of 0.375% bupivacaine with epinephrine for interscalene brachial plexus block for shoulder surgery. Following approval by the Research Ethics Committee, patients with a physical condition of I or II according to the American Society of Anesthesiologists, between 21 and 65 years old and subjected to elective surgery of the shoulder and interscalene brachial plexus block will be recruited. The volume of the anesthetic will be determined using a step-up/step-down method and based on the outcome of the preceding block. Positive or negative block results in a 1mL reduction or increase in volume, respectively. The success of the block is defined as the presence of motor block in two muscle groups and the absence of thermal and pain sensations in the necessary dermatomes within 30 minutes of the injection. Diaphragmatic paralysis, pulmonary function and analgesia will be quantified at 30 minutes, 4 and 6 hours. Data will undergo statistical analysis in order to determine minimum effective volume of 0.375% bupivacaine and, secondarily, the maximum volume that maintains the diaphragmatic function, evaluate diaphragm paralysis and its influence in pulmonary function.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 33
• Est. completion date: September 2013
• Est. primary completion date: January 2013
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 21 Years to 65 Years

Eligibility

Inclusion Criteria:

• Age between 21 and 65 years

• Candidates for an elective surgical intervention on the shoulder with indication for anesthesia via brachial plexus block

• Physical condition of I or II according to the American Society of Anesthesiologists

• Body mass index up to 35 kg.m-2

Exclusion Criteria:

• Chronic obstructive pulmonary disease

• Cognitive impairment or active psychiatric condition

• Infection at the site of the puncture for the block

• Coagulopathy

• Bupivacaine allergy

Study Design

Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Shoulder Surgery

Intervention

Drug:
• Bupivacaine 0,375%
Positive or negative block results in a 1-mL reduction or increase in volume, respectively.

Locations

Country	Name	City	State
Brazil	Federal University of Sao Paulo	Sao Paulo

Sponsors (1)

Lead Sponsor	Collaborator
Federal University of São Paulo

Country where clinical trial is conducted

Brazil, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Minimum effective volume of 0,375% bupivacaine	Minimum effective volume of 0,375% bupivacaine with epinephrine in ultrasound-guided interscalene brachial plexus block for shoulder surgery	30 minutes	No
Secondary	Maximum 0,375% bupivacaine volume that maintains the diaphragmatic function	Maximum effective volume of 0,375% bupivacaine with epinephrine in ultrasound-guided interscalene brachial plexus block for shoulder surgery without diaphragmatic block	Before block, 10, 20 and 30 minutes, 4 and 6 hours after	No
Secondary	Pulmonary function	Spirometric evaluation of forced vital capacity	Before block, 30 minutes, 4 and 6 hours after	No
Secondary	Diaphragmatic Function	Diaphragmatic movement on ultrasound	Before block, 30 minutes, 4 and 6 hours after	No