Interscalene Brachial Plexus Block Washout to Reverse Inadvertent Phrenic Nerve Blockade

July 28, 2022 updated by: Chi-Ho Ban Tsui, Stanford University

One of the most frequently performed peripheral nerve blocks (the injection of local anesthetic near nerves to block sensation/ movement to a specific part of the body) is the interscalene brachial plexus block for upper extremity surgeries. This type of block can unmask underlying respiratory issues such as shortness of breath due to a well-known and typically insignificant side effect of temporary diaphragmatic paralysis.

The nerve block may be able to use saline solution to wash out the local anesthetic and potentially reverse this respiratory side effect. Specifically, the goal of this study is to determine if the injection of saline through the nerve block catheter reverses blockade of the phrenic nerve supplying the diaphragm, without affecting the ability of the nerve block to provide pain control after surgery.

Study Overview

Study Type

Interventional

Enrollment (Actual)

43

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • California
      • Palo Alto, California, United States, 94304
        • Stanford Health Care (SHC)

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion criteria:

  • All adult patients (18 years and over) scheduled for surgery requiring a continuous interscalene brachial plexus nerve block catheter as part of their anesthetic care.

Exclusion criteria:

  • Concomitant life-threatening injuries and other concomitant injuries causing significant pain
  • Pregnant
  • Any condition impairing patient's ability to consent to participation in study, and an existing condition contraindicating a nerve block, i.e. nerve injury, existing bleeding disorder, infection in the vicinity of the block, and patient refusal.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Placebo group
After surgery, in the post-operative recovery room, patients randomized to both the intervention and control groups will have 10cc 0.5% ropivacaine bolused via their nerve catheters. After 30 minutes, the following will be measured/assessed: spirometry data, pain scores (using the Numeric Rating Scale), and, if time is sufficient, bilateral diaphragmatic excursion via ultrasonography and brachial plexus motor and sensory exams. This control group will have no normal saline injected into their nerve catheter (no intervention). Then, both the control and treatment groups will have the following measured/assessed after 5, 15 and 30 minutes: spirometry data, pain scores (using the Numeric Rating Scale), and, if time is sufficient, bilateral diaphragmatic excursion via ultrasonography and brachial plexus motor and sensory exams. Investigators will be blinded to whether the patient is in the intervention or treatment group.
With the catheter covered, placebo group patients will go through the same steps as the treatment group, but no solution will be injected into the interscalene nerve block catheter.
Active Comparator: Treatment group
After surgery, in the post-operative recovery room, patients randomized to both the intervention and control groups will have 10cc 0.5% ropivacaine bolused via their nerve catheters. After 30 minutes, the following will be measured/assessed: spirometry data, pain scores (using the Numeric Rating Scale), and, if time is sufficient, bilateral diaphragmatic excursion via ultrasonography and brachial plexus motor and sensory exams. This group will then have 30ml of normal saline injected into their nerve catheter. Then, both the control and treatment groups will have the following measured/assessed after 5, 15 and 30 minutes: spirometry data, pain scores (using the Numeric Rating Scale), and, if time is sufficient, bilateral diaphragmatic excursion via ultrasonography and brachial plexus motor and sensory exams. Investigators will be blinded to whether the patient is in the intervention or treatment group.
With the catheter covered, treatment group patients will receive a normal saline (NS) bolus regimen (30cc 0.9% NS) via their interscalene nerve block catheter.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in forced vital capacity (FVC)
Time Frame: Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments)
Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment.
Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments)
Change in peak expiratory flow (PEF)
Time Frame: Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments)
Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment.
Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments)
Change in forced expiratory volume in 1 second (FEV1)
Time Frame: Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments)
Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment.
Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Diaphragmatic excursion
Time Frame: Before nerve block is placed, within 1 hour after the surgery, and while receiving either the placebo or treatment (5 minutes each for a total of 3 assessments.)
Diaphragmatic excursion will be assessed via ultrasound before nerve block is placed, after surgery, and while receiving either the placebo or treatment.
Before nerve block is placed, within 1 hour after the surgery, and while receiving either the placebo or treatment (5 minutes each for a total of 3 assessments.)
Brachial plexus sensory and motor exam
Time Frame: Before nerve block is placed, within 1 hour after the surgery, and while receiving either the placebo or treatment (2 minutes each for a total of 3 assessments).
Brachial plexus sensory and motor exam changes will be assessed before nerve block is placed, after surgery, and while receiving either the placebo or treatment.
Before nerve block is placed, within 1 hour after the surgery, and while receiving either the placebo or treatment (2 minutes each for a total of 3 assessments).
Pain scores
Time Frame: Pain scores will be assessed before nerve block is placed, within 1 hour after the surgery, while receiving either the placebo or treatment. (1 minute each for a total of 3 assessments)
The Numerical Pain Rating Scale is a subjective measure in which individuals rate their pain on an eleven-point numerical scale. The scale is composed of 0 (no pain at all) to 10 (worst imaginable pain). Pain scores will be assessed before nerve block is placed, after surgery, while receiving either the placebo or treatment.
Pain scores will be assessed before nerve block is placed, within 1 hour after the surgery, while receiving either the placebo or treatment. (1 minute each for a total of 3 assessments)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Ban Tsui, MD, Stanford University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

October 22, 2018

Primary Completion (Actual)

July 7, 2022

Study Completion (Actual)

July 7, 2022

Study Registration Dates

First Submitted

September 18, 2018

First Submitted That Met QC Criteria

September 18, 2018

First Posted (Actual)

September 19, 2018

Study Record Updates

Last Update Posted (Actual)

August 2, 2022

Last Update Submitted That Met QC Criteria

July 28, 2022

Last Verified

July 1, 2022

More Information

Terms related to this study

Other Study ID Numbers

  • 46830

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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