CClinicalTrials.gg
CompletedNCT03677778Updated Aug 2, 2022

Interscalene Brachial Plexus Block Washout to Reverse Inadvertent Phrenic Nerve Blockade

An interventional study of Normal saline injected via interscalene nerve catheter and Placebo in Anesthesia, Local, Phrenic Nerve Paralysis and Upper Extremity Injury, sponsored by Stanford University. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2022-08-02.

Sponsored by Stanford University · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
43
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

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.

02

Conditions studied

  • Anesthesia, Local
  • Phrenic Nerve Paralysis
  • Upper Extremity Injury
  • Phrenic Nerve Palsy on the Left
  • Phrenic Nerve Palsy on the Right
03

In context

Paralysis

751 studies on the registry are indexed under Paralysis; 134 are open to participants now.

This study's enrollment of 43 is above the median of 30 across 538 interventional studies indexed under Paralysis.

Browse Paralysis studies →

Lead sponsor

Stanford University is the lead sponsor of 2,117 studies on the registry; 425 are open to participants now.

Of its 259 completed or terminated interventional studies of FDA-regulated products, 197 (76%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

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

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.
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Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Investigator)
Enrollment
43 participants (actual)

Study arms

  • 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.

    Other: Placebo

  • 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.

    Procedure: Normal saline injected via interscalene nerve catheter

Interventions

  • ProcedureNormal saline injected via interscalene nerve catheter

    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.

  • OtherPlacebo

    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.

06

What researchers measure

Primary outcomes

  1. Change in forced vital capacity (FVC)

    Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment.

    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)

  2. Change in peak expiratory flow (PEF)

    Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment.

    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)

  3. Change in forced expiratory volume in 1 second (FEV1)

    Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment.

    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)

Secondary outcomes

  1. Diaphragmatic excursion

    Diaphragmatic excursion will be assessed via ultrasound before nerve block is placed, after surgery, and while receiving either the placebo or treatment.

    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.)

  2. Brachial plexus sensory and motor exam

    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.

    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).

  3. Pain scores

    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.

    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)

07

Study locations

1 site
  • Stanford Health Care (SHC)
    Palo Alto, California 94304, United States
08

References and documents

Publications

  • Urmey WF, Talts KH, Sharrock NE. One hundred percent incidence of hemidiaphragmatic paresis associated with interscalene brachial plexus anesthesia as diagnosed by ultrasonography. Anesth Analg. 1991 Apr;72(4):498-503. doi: 10.1213/00000539-199104000-00014. PubMed 2006740 ↗
  • Urmey WF, McDonald M. Hemidiaphragmatic paresis during interscalene brachial plexus block: effects on pulmonary function and chest wall mechanics. Anesth Analg. 1992 Mar;74(3):352-7. doi: 10.1213/00000539-199203000-00006. PubMed 1539813 ↗
  • Lenters TR, Davies J, Matsen FA 3rd. The types and severity of complications associated with interscalene brachial plexus block anesthesia: local and national evidence. J Shoulder Elbow Surg. 2007 Jul-Aug;16(4):379-87. doi: 10.1016/j.jse.2006.10.007. Epub 2007 Apr 19. PubMed 17448698 ↗
  • Zink W, Graf BM. Local anesthetic myotoxicity. Reg Anesth Pain Med. 2004 Jul-Aug;29(4):333-40. doi: 10.1016/j.rapm.2004.02.008. PubMed 15305253 ↗
  • Katircioglu K, Ozkalkanli MY, Kalfaoglu H, Sannav S, Ozgurbuz U, Savaci S. Reversal of prilocaine epidural anesthesia using epidural saline or ringer's lactate washout. Reg Anesth Pain Med. 2007 Sep-Oct;32(5):389-92. doi: 10.1016/j.rapm.2007.06.004. PubMed 17961836 ↗
  • Park EY, Kil HK, Park WS, Lee NH, Hong JY. Effect of epidural saline washout on regression of sensory and motor block after epidural anaesthesia with 2% lidocaine and fentanyl in elderly patients. Anaesthesia. 2009 Mar;64(3):273-6. doi: 10.1111/j.1365-2044.2008.05746.x. PubMed 19302639 ↗
  • Sitzman BT, DiFazio CA, Playfair PA, Stevens RA, Hanes CF, Herman TB, Yates HK, Leisure GS. Reversal of lidocaine with epinephrine epidural anesthesia using epidural saline washout. Reg Anesth Pain Med. 2001 May-Jun;26(3):246-51. doi: 10.1053/rapm.2001.22587. PubMed 11359224 ↗
  • Ip VH, Tsui BC. Continuous interscalene block: the good, the bad and the refined spread. Acta Anaesthesiol Scand. 2012 Apr;56(4):526-30. doi: 10.1111/j.1399-6576.2012.02650.x. Epub 2012 Feb 16. PubMed 22338616 ↗
  • Courtney KR, Kendig JJ, Cohen EN. Frequency-dependent conduction block: the role of nerve impulse pattern in local anesthetic potency. Anesthesiology. 1978 Feb;48(2):111-7. No abstract available. PubMed 306789 ↗
  • Gerber LN, Sun LY, Ma W, Basireddy S, Guo N, Costouros J, Cheung E, Boublik J, Horn JL, Tsui BC. Clinical effect of normal saline injectate into interscalene nerve block catheters given within one hour of local anesthetic bolus on analgesia and hemidiaphragmatic paralysis. Reg Anesth Pain Med. 2021 Feb;46(2):124-129. doi: 10.1136/rapm-2020-101922. Epub 2020 Nov 12. PubMed 33184166 ↗

Individual participant data

Plan to share: No

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Aug 2, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03677778
Lead sponsor
Stanford University
Responsible party
Chi-Ho Ban Tsui (Professor, Stanford University) — Principal investigator
First posted
Sep 19, 2018
Start date
Oct 22, 2018
Primary completion
Jul 7, 2022
Completion
Jul 7, 2022
Last update
Aug 2, 2022

Study contacts

Ban Tsui, MD
principal investigator · Stanford University

Oversight

FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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