Breathing Device for Orthostatic Hypotension (OH)

Study Overview
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Brief Summary
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The investigators will test whether breathing through an inspiratory resistance device will improve the ability to be upright and decrease blood pressure drops on standing in patients with orthostatic hypotension.

Detailed Description
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Orthostatic hypotension is commonly described, especially in an elderly population. Using data from a national hospital inpatient database, Shibao et al. have reported that the annual hospitalization rate for orthostatic hypotension was 233 per 100000 among patients older than 75 years. Orthostatic hypotension is associated with an increased risk of falls, increased risk of coronary heart disease and mortality. Orthostatic hypotension is defined as a fall in systolic blood pressure of at least 20 mmHg within 3 minutes upon standing 3. Patients with orthostatic hypotension commonly experience lightheadedness or syncope. In normal individuals, changes in posture do not results in significant changes in blood pressure due to physiological compensation for the gravity-mediated pooling of blood in the lower limbs with upright posture. Unfortunately, in patients with impairments of the autonomic nervous system, one or more of these adaptive mechanisms fail, and an orthostatic fall in blood pressure results. In this pilot study, we will test the hypothesis that breathing through an inspiratory resistance device will improve orthostatic tolerance and reduce orthostatic hypotension in patients with neurogenic orthostatic hypotension.

Official Title
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Assessment of Inspiratory Breathing Devices to Improve Orthostatic Tolerance in Neurogenic Orthostatic Hypotension

Conditions
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Orthostatic Hypotension

Intervention / Treatment
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* Device: Inspiratory Threshold Device (Res-Q-Gard ITD)
* Device: Sham Inspiratory Threshold Device


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosed with neurogenic orthostatic hypotension by the Vanderbilt Autonomic Dysfunction Center Decrease in systolic blood pressure ≥ 20 mmHg with position change from supine to standing (10 minutes) Evidence of reproducibility suggestive of non-reversible nervous system origin for the orthostatic hypotension Age between 18-80 years Male and female subjects are eligible Able and willing to provide informed consent Exclusion Criteria: Overt cause for orthostatic hypotension (such as acute dehydration) Inability to give, or withdrawal of, informed consent Pregnant Other factors which in the investigator's opinion would prevent the subject from completing the protocol

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ITD breathing device<br>Breathing through the Res-Q-Gard ITD device from Advanced Circulatory Systems Inc. | Device: Inspiratory Threshold Device (Res-Q-Gard ITD)<br>* Patient will breathe through this device attached to a mouthpiece during assessment of orthostatic tolerance.<br>* Other names: Res-Q-Gard ITD device 7.0 (Ref:12-0463-000);|
| Sham Comparator: Sham Device<br>Breathing device similar to active Res-Q-Gard device but with one-way resistance valve removed. | Device: Sham Inspiratory Threshold Device<br>* Breathing through device similar to active device but with the one-way threshold valve removed.<br>* Other names: Res-Q-Gard device 7.0 (with active valve removed);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Magnitude of drop in Systolic Blood Pressure during head-up tilt |  | 1 min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Standing Time tolerated with systolic blood pressure above 70 mmHg |  | 10 min (max) | 
| Symptom rating |  | 10 min (max) | 
| Hemodynamics (non-invasive) |  | 10 min | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Orthostatic hypotension, Breathing, Blood pressure, standing