Changes in Skin Conductance Measurement as an Endpoint Monitor for Sympathetic Blocks

NCT02390323 | Completed Results

• 1 other identifier: 2012-012
• Study Type: interventional
• Target: 13
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study is intended to evaluate a monitor that will facilitate ascertainment of an effective sympathetic blockade following Lumbar Sympathetic blocks. Utilization of a monitor with a rapid response and easy clinical applicability which can demonstrate effective sympathetic block would increase efficiency within the procedure suite and also serve to function as an objective endpoint for the evaluation of sympathetic blockade in future research.In current clinical practice, the most commonly used monitoring methods are clinical observations of sympathetic blockade, skin temperature monitoring, pulse pressure monitoring and any combination of these monitoring methods. The skin temperature and pulse pressure may increase after sympathetic block. However, changes in the skin temperature and pulse pressure often demonstrate an unpredictable or delayed response. Confounding variables, such as ambient temperature, coexisting vascular disease, use of other vasoactive medications may contribute to inconsistencies in the temperature or pulse pressure responses. Normal sympathetic activity stimulates muscarinic receptors in the periphery that subsequently stimulate the sweat glands to secrete and fill with sweat containing sodium and other electrolytes. The electrolytes present in the sweat increase the electrical conductance while decreasing the electrical resistance at the skin level. The real-time changes in skin conductance indices can be monitored at the skin level, by use of non-invasive electrodes attached to the skin (similar to EKG electrodes). A computer program analyzes the data and produces a real-time graphic and numeric data demonstrating the skin conductance response. The initiation of successful sympathetic blockade can cause rapid cessation of the skin sympathetic activity that leads to a decrease in skin conductance within seconds.

Conditions

Nerve; Disorder, Sympathetic

Outcome Measures

Primary Outcomes (6)

• Time to Indication of Successful Blockade Between the Skin Conductance Numeric Value and Bilateral Thermometry.

  The skin conductance monitor will be applied immediately prior to the beginning of the procedure. Measurements will be recorded at 0 minutes and every 1 minute until 10 minutes after completion of procedure. Additional measurements will be recorded at the following time points: 1. Prior to start of procedure (Baseline measurement) 2. Infiltration of Local Anesthetic 3. Insertion of the needle 4. Start of block (First local anesthetic injection after the test dose) 5. End of block 6. End of Procedure/Removal of monitor

  10 minutes

• Difference in Time to Indication of Successful Blockade Between the Skin Conductance Numeric Value and Unilateral Thermometry.

  10 minutes

• Hazard Ratio for Time to Successful Blockade Between the Skin Conductance Numeric Value and Plethysmography.

  Hazard Ratios are calculated using a Cox proportional Hazards model to compare each traditional method to SCM using a marginal approach with a working independence assumption to account for the correlation between measurements on the same patients. A lower score is a better outcome.

  10 minutes

• Hazard Ratio for Difference in Time to Indication of Successful Blockade Between the Skin Conductance Numeric Value and Subjective Temperature Difference.

  Hazard Ratio for Time to Indication of Successful Blockade Between the Skin Conductance Numeric Value and Subjective Temperature Difference. Hazard Ratios are calculated using a Cox proportional Hazards model to compare each traditional method to SCM using a marginal approach with a working independence assumption to account for the correlation between measurements on the same patients. A lower score is a better outcome.

  10 minutes

• Hazard Ratio for Time to Indication of Successful Blockade Between the Skin Conductance Numeric Value and Clinically Visible Hyperemia.

  Hazard Ratios are calculated using a Cox proportional Hazards model to compare each traditional method to SCM using a marginal approach with a working independence assumption to account for the correlation between measurements on the same patients. The skin conductance monitor will be applied immediately prior to the beginning of the procedure. Measurements will be recorded at 0 minutes and every 1 minute until 10 minutes after completion of procedure. Additional measurements will be recorded at the following time points: 1. Prior to start of procedure (Baseline measurement) 2. Infiltration of Local Anesthetic 3. Insertion of the needle 4. Start of block (First local anesthetic injection after the test dose) 5. End of block 6. End of Procedure/Removal of monitor A lower score is a better outcome.

  10 minutes

• Hazard Ratio for Difference in Time to Indication of Successful Blockade Between the Skin Conductance Numeric Value and Clinically Visible Engorgement of Veins.

  Hazard Ratios are calculated using a Cox proportional Hazards model to compare each traditional method to SCM using a marginal approach with a working independence assumption to account for the correlation between measurements on the same patients. The skin conductance monitor will be applied immediately prior to the beginning of the procedure. Measurements will be recorded at 0 minutes and every 1 minute until 10 minutes after completion of procedure. Additional measurements will be recorded at the following time points: 1. Prior to start of procedure (Baseline measurement) 2. Infiltration of Local Anesthetic 3. Insertion of the needle 4. Start of block (First local anesthetic injection after the test dose) 5. End of block 6. End of Procedure/Removal of monitor A lower score is a better outcome.

  10 minutes

Study Arms (1)

Lumbar Sympathetic Block

EXPERIMENTAL

Patients receiving a Lumbar Sympathetic Block as treatment for lower extremity pain. Skin conductance algesimeter will be used to measure sympathetic activity.

Procedure: Lumbar Sympathetic Block; Device: Skin conductance algesimeter

Interventions

Lumbar Sympathetic Block PROCEDURE

A lumbar sympathetic block is an injection in the middle of the lower back, toward the left or right side. The "lumbar sympathetic nerves" are a small bundle of nerves that carries "sympathetic" nerve signals from the lower extremities. In some instances, certain injuries to the lower extremities can cause a burning, unusual pain called complex regional pain syndrome or reflex sympathetic dystrophy. Injecting a small amount of local anesthetic on the lumbar sympathetic nerves can identify whether or not this pain is carried by the sympathetic nervous system.

Lumbar Sympathetic Block

Skin conductance algesimeter DEVICE

The real-time changes in skin conductance indices can be monitored at the skin level, by use of non-invasive electrodes attached to the skin (similar to EKG electrodes) connected to the skin conductance algesimeter. A computer program analyzes the data and produces a real-time graphic and numeric data demonstrating the skin conductance response. The initiation of successful sympathetic blockade can cause rapid cessation of the skin sympathetic activity that leads to a decrease in skin conductance within seconds.

Lumbar Sympathetic Block

Eligibility Criteria

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

You may qualify if:

• Patients presenting for sympathetic block of the lower extremity (lumbar sympathetic block)
• Ages 18-99

You may not qualify if:

• Patients with pacemakers or cardiac defibrillators
• Age \<18
• IV sedation for anxiolysis or analgesia
• Burn patients or patients with severe dermatologic conditions (as defined by skin conditions causing further pain to patients that actively has to be treated)
• Allergy to adhesive tape
• Patient with diagnosis of: Dysautonomia, Sympathetic dysfunction (e.g.,Raynaud disease, Buerger disease) or Disorders of sweating (e.g.,Acquired idiopathic generalized anhidrosis)
• Patients on vasoactive drugs

Sponsors & Collaborators

• Hospital for Special Surgery, New York: lead
• Oslo University Hospital: collaborator

Related Publications (1)

• Storm H. Changes in skin conductance as a tool to monitor nociceptive stimulation and pain. Curr Opin Anaesthesiol. 2008 Dec;21(6):796-804. doi: 10.1097/ACO.0b013e3283183fe4.

  PMID: 18997532 BACKGROUND

Results Point of Contact

• Title: Semih Gungor
• Organization: Hospital for Special Surgery

gungors@hss.edu

212-606-1206

Study Officials

• Semih Gungor, MD

  Hospital for Special Surgery, New York

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: SUPPORTIVE CARE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 17, 2015
• First Posted: March 17, 2015
• Study Start: January 1, 2014
• Primary Completion: September 1, 2014
• Study Completion: September 1, 2014
• Last Updated: August 9, 2022
• Results First Posted: August 9, 2022

Record last verified: 2022-07