The Pathophysiology of Orthostatic Hypotension

Vanderbilt University Medical Center

Status and phase: Completed; Phase 1

Conditions: Autonomic Nervous System Diseases; Orthostatic Intolerance; Dopamine Beta-Hydroxylase Deficiency; Orthostatic Hypotension

Treatments: Procedure: Standing or upright tilt; Procedure: Microneurography; Procedure: Brain function studies; Procedure: Metabolic chamber; Procedure: Pain response testing; Device: neck cuff stimulation; Procedure: Eye exam; Procedure: BodPod; Procedure: QSweat; Procedure: Sleep study; Drug: clonidine,yohimbine,metoclopramide,alpha-methyldopa; Procedure: Bicycle Exercise Test; Drug: phenylephrine,isoproterenol,nitroprusside,propranolol,edrophonium,atropine,tyramine

Study type: Interventional

Funder types: Other

Identifiers

NCT00748059

HL056693

030752

Details and patient eligibility

About

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.

Enrollment: 10 patients

Sex: All

Ages: 12 to 70 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Screening

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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10 participants in 1 patient group

A

Experimental group

Description:

Patients with Orthostatic Hypotension

Treatment:

Procedure: Sleep study

Procedure: QSweat

Procedure: Microneurography

Procedure: Brain function studies

Procedure: Standing or upright tilt

Procedure: Metabolic chamber

Device: neck cuff stimulation

Procedure: Bicycle Exercise Test

Drug: clonidine,yohimbine,metoclopramide,alpha-methyldopa

Procedure: Eye exam

Drug: phenylephrine,isoproterenol,nitroprusside,propranolol,edrophonium,atropine,tyramine

Procedure: BodPod

Procedure: Pain response testing