View clinical trials related to Hypotension, Orthostatic.
Filter by:With upright postures, there is an immediate redistribution of blood to the dependent circulation; venous return and central venous filling pressure are reduced, resulting in diminution of cardiac output and blood pressure. These hemodynamic alterations stimulate the baroreceptor reflex, which is mediated via the central nervous system to increase peripheral sympathetic vasomotor tone, restoring blood pressure and cardiac output within seconds-to-minutes of the assumption of the upright position. Following SCI, individuals often experience the inability to adjust to postural changes due to disruption of central command of the baroreceptor reflex and reduction in efferent sympathetic neural pathways; consequently, orthostatic hypotension (OH) and symptoms of cerebral hypo-perfusion may ensue. OH is a well-documented phenomenon, which is characterized by a fall in systolic blood pressure of >20 mmHg or diastolic BP of > 10 mmHg within 3 minutes of assumption of an upright posture. As a consequence of OH, many individuals experience symptoms of cerebral hypo-perfusion which include lightheadedness, dizziness, blurry vision, fatigue, nausea, ringing in the ears, cognitive impairment and heart palpitations. Although several investigators have reported increased prevalence of OH during the acute phase of spinal cord injury (SCI), individuals with chronic injury also experience significant falls in blood pressure with seated upright postures. This investigation will examine the effects of an alpha-agonist, midodrine hydrochloride, during head-up tilt on systemic blood pressure, cerebral blood flow and cerebral oxygenation compared to placebo administration in persons with chronic SCI who demonstrate significant orthostatic hypotension during a 24-hour observation study. This is the first study to determine the dose response and efficacy of midodrine to improve orthostatic blood pressure and cerebral blood flow and oxygenation in the SCI population.
The purpose of this study is to determine how blood pressure and blood flow are controlled during head-up tilt in a semi-upright position. In this investigation we are studying blood pressure and blood flow to the brain, with and without a medication which lowers blood pressure (Vasotec). We will determine how persons with a spinal cord injury are able to maintain blood flow to the brain (not get dizzy) as they assume a more upright position and their blood pressure decreases.
The autonomic nervous system serves multiple regulatory functions in the body, including the regulation of blood pressure and heart rate, gut motility, sweating and sexual function. There are several diseases characterized by abnormal function of the autonomic nervous system. Medications can also alter autonomic function. Impairment of the autonomic nervous system by diseases or drugs may lead to several symptoms, including blood pressure problems (e.g., high blood pressure lying down and low blood pressure on standing), sweating abnormalities, constipation or diarrhea and sexual dysfunction. Because treatment options for these patients are limited. We propose to study patients autonomic failure and low blood pressure upon standing and determine the cause of their disease by history and examination and their response to autonomic testing which have already been standardized in our laboratory. Based on their possible cause, we will tests different medications that may alleviate their symptoms.
The purpose of this study is to determine the prevalence and clinical course of orthostatic hypotension (OH) on a rehabilitation and nursing home unit during their inpatient stay and to initiate a standardized, interdisciplinary treatment plan for patients with OH and determine the effect of treatment on the clinical course of OH during their inpatient stay.
Patients with Parkinson's Disease or Multiple System Atrophy (MSA), and symptoms of orthostatic hypotension, are eligible for the study. Each patient will have three weeks of conservative therapy, three weeks of therapy with fludrocortisone, and three weeks of therapy with domperidone. Autonomic testing, a symptom questionnaire, bedside blood pressure testing, and Unified Parkinson Disease Rating Scale (UPDRS) will be performed after each intervention.
We are seeking male and female patients to voluntarily take part in a clinical research study. Patients must be aged 18 or older and diagnosed with symptomatic orthostatic hypotension (low blood pressure while in the upright position) due to Parkinson's disease, multiple system atrophy, pure autonomic failure or autonomic neuropathies (i.e. neurogenic orthostatic hypotension). Symptoms of low blood pressure include dizziness, lightheadedness, changes in vision and generalized weakness upon standing. The main effect of the drug being studied is to increase blood pressure in the upright position so symptoms will decrease. The purpose of this clinical study is to further assess the clinical benefit of midodrine hydrochloride (ProAmatine®), an approved treatment for orthostatic hypotension. During the course of the study, participants will receive either ProAmatine® or a placebo. Assessments will be made using questionnaires that measure symptom and activity levels. Blood pressure in the lying down and standing positions will be measured at each visit.
Please note that the continuation study can be found at http://clinicaltrials.gov/show/NCT00633880. RATIONALE: Neurogenic hypotension is a fall in blood pressure that occurs when one moves from a lying down to a standing position or after eating a meal. It causes one to feel dizzy, light headed, and weak. Neurogenic hypotension is caused by a problem in the part of the nervous system that controls such functions as heart rate and blood pressure. Droxidopa, a drug that may increase blood pressure, may be an effective treatment for neurogenic hypotension. PURPOSE: Clinical trial to study the effectiveness of droxidopa in treating patients who have neurogenic hypotension.
OBJECTIVES: I. Study further the safety and efficacy of the alpha-receptor agonist midodrine in patients with neurogenic orthostatic hypotension. II. Assess the quality of life in these patients with this treatment regimen.