Assessment of Hand-grip in the Prevention of Postural Orthostatic Hypotension

Study Overview
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Brief Summary
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The study is aimed to assess the efficacy of hand-grip in preventing orthostatic hypotension in 20 patients diagnosed with autonomic failure. Five healthy subjects will be studied for comparison. The investigators will evaluate the subjects while on tilt table for 10 minutes and than while mounted from lying down to 70 degrees for additional 10 minutes. Blood pressure, heart rate and symptoms will be continuously measured. First study will evaluate the blood pressure changes. Second measure will include hand-grip maneuver 1 minute before the erect positon. Trans cranial Doppler will assess the intracranial blood flow during the position changes.

Detailed Description
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Study 1: 10 minutes lying on the tilt table. Performing TCD study at 10 minutes. Raising the tilt table to 70 degrees. Performing TCD study 5 minutes after tilting. Measuring blood pressure and symptoms for 10 minutes. Returning the tilt bed to supine position. Study 2. in continue with study 1: 10 minutes lying on the tilt table. Performing TCD study at 10 minutes. Performing hand-grip at 50-70% grip force for 1 minute Raising the tilt table to 70 degrees. Performing TCD study 5 minutes after tilting. Measuring blood pressure and symptoms for 10 minutes. Returning the tilt bed to supine position.

Official Title
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Assessment of Hand-grip in the Prevention of Postural Orthostatic Hypotension

Conditions
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Orthostatic Hypotension

Intervention / Treatment
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* Other: Hand grip maneuver


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Man or women 18 years of age or older Diagnosed with orthostatic hypotension due to Parkinson's disease, multiple system atrophy or pure autonomic failure Orthostatic hypotension is not due to drugs, any heart disorder, anemia or dehydration Exclusion Criteria: Pregnant or breast feeding

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patients<br>Patients with autonomic failure. | Other: Hand grip maneuver<br>* Hand grip on blood pressue cuff slightly inflated at 50-70% of maximal force for 1 minute<br>|
| Experimental: Healthy subjects<br>Control group | Other: Hand grip maneuver<br>* Hand grip on blood pressue cuff slightly inflated at 50-70% of maximal force for 1 minute<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in orthostatic blood fall after tilting with and without hand grip. | Patients will be tilted to 70 degrees twice. Hand grip maneuver will be performed 1 minute before the second tilt study and the differences in blood pressure changes [baseline-end tilt (mmHg)] will be compared between the two studies and to those obtained from a healthy control group. | 10 minutes after tilting the subjects. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the intracranial blood flow after tilting with and without hand grip. | Intracranial blood flow will be evaluated by transcranial doppler at baseline and after tilting. Differences will be compared [peak systolic flow (PSW) cm/sec], after tilting with and without prior hand grip and in comparison to tilting a control group. | 10 minutes after tilting. |