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The Pathophysiology of Orthostatic Hypotension

This study is ongoing, but not recruiting participants.
Sponsor:
Information provided by (Responsible Party):
Emily M. Garland, Vanderbilt University Medical Center
ClinicalTrials.gov Identifier:
NCT00748059
First received: September 5, 2008
Last updated: May 19, 2017
Last verified: May 2017
September 5, 2008
May 19, 2017
December 1996
December 2017   (Final data collection date for primary outcome measure)
hemodynamic changes with standing [ Time Frame: following test ]
Same as current
Complete list of historical versions of study NCT00748059 on ClinicalTrials.gov Archive Site
  • blood and urine hormones [ Time Frame: after test ]
  • blood volume [ Time Frame: during supine and/or upright postures ]
  • sympathetic nerve activity [ Time Frame: during stimulation of sympathetic nervous system ]
  • quantitative sweat testing [ Time Frame: 2 hours ]
  • Eye function [ Time Frame: once ]
  • Sleep efficiency [ Time Frame: once ]
  • Metabolic rate [ Time Frame: once ]
  • Pain response [ Time Frame: once ]
  • Responses on questionnaires and computer tasks designed to assess brain function [ Time Frame: once ]
  • blood and urine hormones [ Time Frame: after test ]
  • blood volume [ Time Frame: during supine and/or upright postures ]
  • sympathetic nerve activity [ Time Frame: during stimulation of sympathetic nervous system ]
  • quantitative sweat testing [ Time Frame: 2 hours ]
Not Provided
Not Provided
 
The Pathophysiology of Orthostatic Hypotension
The Pathophysiology of Orthostatic Hypotension
The purpose of this study is to determine the cause of low blood pressure in selective patients who have problems with their involuntary (autonomic) nervous system. These patients frequently have had symptoms throughout their life, and their disorder might have a genetic basis. The biochemical, physiological and pharmacological procedures in this study should help us define the problem and perhaps lead to more effective treatment.
Not Provided
Interventional
Phase 1
Intervention Model: Single Group Assignment
Masking: No masking
Primary Purpose: Screening
  • Autonomic Nervous System Diseases
  • Orthostatic Hypotension
  • Dopamine Beta-Hydroxylase Deficiency
  • Orthostatic Intolerance
  • Procedure: Standing or upright tilt
    stand upright or tilt table test
  • Procedure: Microneurography
    Recording from sympathetic nerve
  • Procedure: QSweat
    quantitative sweat testing
  • Device: neck cuff stimulation
    Blood pressure receptors in the neck arteries may be stimulated by applying suction through a collar around the neck.
  • Drug: phenylephrine,isoproterenol,nitroprusside,propranolol,edrophonium,atropine,tyramine

    IV Pharmacological Testing

    phenylephrine 12.5 - 400 ug, isoproterenol 0.1 - 0.4 ug or higher until desired effect, nitroprusside 0.1 - 1.6 ug/kg, propranolol 1.1 mg/min, edrophonium maximum of 10 mg, atropine .01 mg/kg, tyramine 250-4000 ug or higher until desired effect

  • Drug: clonidine,yohimbine,metoclopramide,alpha-methyldopa

    Oral Pharmacological Testing

    clonidine 0.1-0.3 mg, yohimbine 5-10 mg, metoclopramide 10 mg, alpha-methyldopa 62.5 mg, placebo

  • Procedure: BodPod
    Determination of body composition
  • Procedure: Eye exam

    Examination of pressure in the eye and eyelid fatiguability. The following eyedrops might be used:

    1. 0.5% proparacaine (Alcaine, Allergan, Inc)
    2. Fluress (0.4% benoxinate hydrochloride, fluorescein sodium, Akorn, Inc)
    3. 0.5%, 1% tropicamide (Mydriacyl, Alcon)
    4. Over-the-counter preservative-free artificial tears
    5. 0.25%, 2.5% and 10% phenylephrine (Bausch and Lomb)
    6. 1% cyclopentolate hydrochloride (Alcon)
  • Procedure: Sleep study
    Recording of sleep pattern overnight
  • Procedure: Pain response testing
    Subjects will rate the quality and intensity of 2 pain tasks.
  • Procedure: Metabolic chamber
    Determination of metabolic rate via 24hr stay in whole-room indirect calorimeter
  • Procedure: Brain function studies
    Questionnaires and computer tasks, an EEG and an MRI may be used to assess brain function.
  • Procedure: Bicycle Exercise Test
    Blood pressure and heart rate may be monitored while exercising on a stationary bicycle.
Experimental: A
Patients with Orthostatic Hypotension
Interventions:
  • Procedure: Standing or upright tilt
  • Procedure: Microneurography
  • Procedure: QSweat
  • Device: neck cuff stimulation
  • Drug: phenylephrine,isoproterenol,nitroprusside,propranolol,edrophonium,atropine,tyramine
  • Drug: clonidine,yohimbine,metoclopramide,alpha-methyldopa
  • Procedure: BodPod
  • Procedure: Eye exam
  • Procedure: Sleep study
  • Procedure: Pain response testing
  • Procedure: Metabolic chamber
  • Procedure: Brain function studies
  • Procedure: Bicycle Exercise Test
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Active, not recruiting
25
December 2017
December 2017   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • severe orthostatic hypotension and other autonomic symptoms but do not meet criteria for standard diagnosis
  • non-smokers
  • drug-free
  • able to give informed consent
  • free of pulmonary, renal, hematopoietic, hepatic and cardiac disease

Exclusion Criteria:

  • medications affecting the autonomic nervous system
  • any chronic illness
  • anemia (Hct<30)
  • women of childbearing age who are pregnant or nursing
  • smokers
Sexes Eligible for Study: All
12 Years to 70 Years   (Child, Adult, Senior)
No
Contact information is only displayed when the study is recruiting subjects
United States
 
 
NCT00748059
030752
HL056693
No
Not Provided
Not Provided
Not Provided
Emily M. Garland, Vanderbilt University Medical Center
Vanderbilt University Medical Center
Not Provided
Principal Investigator: Emily M Garland, PhD Vanderbilt University
Vanderbilt University Medical Center
May 2017

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP