Effects of Technique on the Local Anesthetic Dose Required for Interscalene Brachial Plexus Block

NCT00731146 | Unknown

• 1 other identifier: SHSCA02
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

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 be randomly assigned to a group to undergo ISBPB under ultrasound or nerve stimulator guidance. Each group will initially receive 10mL of local anesthetic. 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 2.5mL, while a success will cause the volume to decrease by the same amount. We hypothesize that the minimum effective anesthetic volume in 50% of patients will be significantly lower in the ultrasound guided group than in the nerve stimulator group. We further hypothesize that this lower volume will lead to a decreased rate of complications.

Conditions

Arthroscopic Shoulder Surgery

Keywords

Interscalene Brachial Plexus Block; Regional Anesthesia; Ultrasound guided peripheral nerve block; Minimum Effective Anesthetic Volume; Nerve Stimulator guided peripheral nerve block

Outcome Measures

Primary Outcomes (1)

• Pain Rating as based on 11 point NRS scale

  within 30 minutes or less post-surgery

Secondary Outcomes (1)

• Diaphragmatic Function (as assessed by diaphragmatic movement on ultrasound)

  within 30 minutes post-block

Study Arms (2)

1 - Ultrasound

ACTIVE COMPARATOR

Participants will receive an ultrasound guided interscalene brachial plexus block

Other: Ultrasound Minimum Effective Anesthetic Volume

2 - Nerve Stimulator

ACTIVE COMPARATOR

Participants will receive a nerve stimulator guided interscalene brachial plexus block

Other: Nerve Stimulator Minimum Effective Anesthetic Volume

Interventions

Ultrasound Minimum Effective Anesthetic Volume OTHER

Each sequential participant in this group will be assigned a dose based on the success or failure of the previous participant's block. The starting dose will be 10mL of 0.5% ropivacaine. Each success will decrease the dose by 2.5mL and each failure will subsequently increase the dose by 2.5mL.

1 - Ultrasound

Nerve Stimulator Minimum Effective Anesthetic Volume OTHER

Each sequential participant in this group will be assigned a dose based on the success or failure of the previous participant's block. The starting dose will be 10mL of 0.5% ropivacaine. Each success will decrease the dose by 2.5mL and each failure will subsequently increase the dose by 2.5mL.

2 - Nerve Stimulator

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients receiving interscalene brachial plexus block for arthroscopic shoulder surgery

You may not qualify if:

• ASA \>III, and body mass index (BMI) \>35, pre-existing chronic obstructive pulmonary disease (COPD), unstable asthma, psychiatric history, renal or hepatic impairment, allergy to ropivacaine, and opioid tolerance (\>30 mg oral morphine or equivalent per day).

Sponsors & Collaborators

• Sunnybrook Health Sciences Centre: lead

Study Sites (1)

Sunnybrook Health Sciences Centre

Toronto, Ontario, M4N 3M5, Canada

RECRUITING

Study Officials

• Colin J McCartney, MD

  Sunnybrook Health Sciences Centre

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Colin J McCartney, MD

CONTACT

416-480-6100; cjlmccartney@sympatico.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: August 5, 2008
• First Posted: August 8, 2008
• Study Start: August 1, 2008
• Primary Completion: February 1, 2009
• Study Completion: July 1, 2009
• Last Updated: August 8, 2008

Record last verified: 2008-08

Locations

CA (1)