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The Effects of Horner's Syndrome Developing After Interscalene Brachial Plexus Block on Autonomic Nervous Activity

Completed
Conditions
Brachial Plexus Block
Horner Syndrome
Autonomic Imbalance
Interventions
Procedure: Interscalene brachial plexus block
Registration Number
NCT03514342
Lead Sponsor
Daegu Catholic University Medical Center
Brief Summary

This study evaluates the effects of Horner's syndrome on cardiac autonomic nervous activity after interscalene brachial plexus block. Cardiac autonomic nervous activity and bilateral pupil diameters will be measured in a scotopic light condition, 30 minutes after interscalene brachial plexus block under ultrasound guidance and 15 minutes after the subsequent sitting position.

Detailed Description

Stellate ganglia provide sympathetic fibers to the heart. Ipsilateral stellate ganglion block accompanied by interscalene brachial plexus block causes Horner's syndrome presenting with miosis, ptosis, and anhidrosis. The extent of Horner's syndrome can be represented by the difference in pupil diameter between bilateral eyes. Cardiac autonomic nervous activity affected by stellate ganglion block can be measured by calculation of heart rate variability parameters.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
48
Inclusion Criteria
  • American Society of Anesthesiologists physical status 1
  • Arthroscopic shoulder surgery under interscalene brachial plexus block
Exclusion Criteria
  • Coagulopathy
  • Infection at the site of brachial plexus block
  • Peripheral neuropathy or neurologic sequelae on the operative limb
  • Allergy to local anesthetics or history of allergic shock
  • Psychiatric diseases
  • Patient refusal
  • Difficulty communicating with medical personnel
  • Arrhythmias
  • Ischemic heart disease
  • Hypertension
  • Diabetes mellitus
  • Thyroid dysfunction
  • Conduction abnormalities on electrocardiogram
  • Electrolyte imbalance
  • Medications affecting cardiac conduction
  • Contralateral vocal cord palsy
  • Contralateral hemidiaphragmatic paresis or paralysis
  • Contralateral pneumothorax or hemothorax

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Interscalene brachial plexus blockInterscalene brachial plexus blockUltrasound-guided interscalene brachial plexus block with 25 ml to 30 ml of 0.75% ropivacaine
Interscalene brachial plexus block0.75% ropivacaineUltrasound-guided interscalene brachial plexus block with 25 ml to 30 ml of 0.75% ropivacaine
Primary Outcome Measures
NameTimeMethod
Post-sitting sympathetic nervous activity15 minutes after the sitting position following interscalene brachial plexus block

Natural-log transformed low frequency power of heart rate variability calculated using R wave to R wave intervals obtained for 5 minutes between 10 and 15 minutes after the sitting position following interscalene brachial plexus block

Secondary Outcome Measures
NameTimeMethod
Pre-anesthetic sympathovagal balance15 minutes after baseline acclimiation

Low-to-high frequency power ratio of heart rate variability 15 minutes after baseline acclimation

Pre-anesthetic contralateral pupil diameter15 minutes after baseline acclimation

Contralateral pupil diameter measured under a mesopic condition 15 minutes after baseline acclimation

Pre-anesthetic overall variability of autonomic nervous system15 minutes after baseline acclimation

Natural-log transformed total power of heart rate variability 15 minutes after baseline acclimation

Post-sitting ipsilateral pupil diameter15 minutes after the sitting position following interscalene brachial plexus block

Ipsilateral pupil diameter measured under a mesopic condition 15 minutes after the sitting position following interscalene brachial plexus block

Post-sitting contralateral pupil diameter15 minutes after the sitting position following interscalene brachial plexus block

Contralateral pupil diameter measured under a mesopic condition 15 minutes after the sitting position following interscalene brachial plexus block

Post-anesthetic ipsilateral pupil diameter30 minutes after interscalene brachial plexus block

Ipsilateral pupil diameter measured under a mesopic condition 30 minutes after interscalene brachial plexus block

Post-anesthetic contralateral pupil diameter30 minutes after interscalene brachial plexus block

Contralateral pupil diameter measured under a mesopic condition 30 minutes after interscalene brachial plexus block

Pre-anesthetic ipsilateral pupil diameter15 minutes after baseline acclimation

Ipsilateral pupil diameter measured under a mesopic condition 15 minutes after baseline acclimation

Post-sitting parasympathetic nervous activity15 minutes after the sitting position following interscalene brachial plexus block

Natural-log transformed high frequency power of heart rate variability calculated using R wave to R wave intervals obtained for 5 minutes between 10 and 15 minutes after the sitting position following interscalene brachial plexus block

Post-sitting sympathovagal balance15 minutes after the sitting position following interscalene brachial plexus block

Low-to-high frequency power ratio of heart rate variability obtained for 5 minutes between 10 and 15 minutes after the sitting position following interscalene brachial plexus block

Post-sitting overall variability of autonomic nervous system15 minutes after the sitting position following interscalene brachial plexus block

Natural-log transformed total power of heart rate variability obtained for 5 minutes between 10 and 15 minutes after the sitting position following interscalene brachial plexus block

Post-anesthetic sympathetic nervous activityBetween 25 and 30 minutes after interscalene brachial plexus block

Natural-log transformed low frequency power of heart rate variability between 25 and 30 minutes after interscalene brachial plexus block

Post-anesthetic parasympathetic nervous activityBetween 25 and 30 minutes after interscalene brachial plexus block

Natural-log transformed high frequency power of heart rate variability between 25 and 30 minutes after interscalene brachial plexus block

Post-anesthetic sympathovagal balanceBetween 25 and 30 minutes after interscalene brachial plexus block

Low-to-high frequency power ratio of heart rate variability between 25 and 30 minutes after interscalene brachial plexus block

Post-anesthetic overall variability of autonomic nervous systemBetween 25 and 30 minutes after interscalene brachial plexus block

Natural-log transformed total power of heart rate variability between 25 and 30 minutes after interscalene brachial plexus block

Pre-anesthetic sympathetic nervous activity15 minutes after baseline acclimiation

Natural-log transformed low frequency power of heart rate variability 15 minutes after baseline acclimation

Pre-anesthetic parasympathetic nervous activity15 minutes after baseline acclimiation

Natural-log transformed high frequency power of heart rate variability 15 minutes after baseline acclimation

Sensory blockade30 minutes after interscalene brachial plexus block

C5 to T1 dermatomal blockade of the shoulder graded from 0 to 2 (0 = no cold sensation, 1 = reduced cold sensation, and 2 = normal cold sensation) by applying ice to the shoulder

Motor blockade30 minutes after interscalene brachial plexus block

Motor blockade of the radial, ulnar, median, musculocutaneous, and axillary nerves graded from 0 to 2 (0 = no block 1 = partial block, and 2 = complete block)

Trial Locations

Locations (1)

Daegu Catholic University Medical Center

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Daegu, Korea, Republic of

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