View clinical trials related to Hypotension, Orthostatic.
Filter by:Neurogenic orthostatic hypotension occurs in a significant number of people and has no effective treatment. Neurogenic orthostatic hypotension is associated with intermittent episodes of fainting which can be debilitating for the patients. Using sinusoidal galvanic vestibular stimulation, an oscillating current between the two ears, collaborators have discovered an effective technique to habituate anesthetized rats that develop vasovagal responses. The investigators propose to determine whether a similar use of sinusoidal galvanic vestibular stimulation can eliminate or alleviate neurogenic orthostatic hypotension and the associated syncope in susceptible human subjects. If so, then sinusoidal galvanic vestibular stimulation, which is safe and widely used to study muscle sympathetic nerve activity, can be used in humans, who have a history of syncope and a positive tilt test to habituate vasovagal responses. Habituation will be accomplished using repetitive periods of sinusoidal galvanic vestibular stimulation in two 30min sessions three times/week for 2 weeks. Similar 1 hour sessions are routinely used by others when activating muscle sympathetic nerve activity with sinusoidal galvanic vestibular stimulation without harm to the subjects. The 30 min periods were chosen because this was effective in producing habituation of vasovagal responses. The habituating stimulus will be given by applying paste electrodes over the mastoid processes and plugging the leads into a battery driven-stimulus box, which when activated by a switch, will provide a very low frequency bipolar, ± 2 mA, 0.025 Hz oscillating current sinusoidal galvanic vestibular stimulation between the mastoids. Subjects will be seated during the stimulation. The onset and end of the stimulation period will be denoted by tones, and the subjects will be free to watch television, read, or listen to music while they are being stimulated. The effectiveness of the habituation will be determined in several ways: 1) Subjects will keep a history of the number of episodes of syncope in the inter-test intervals. 2) They will have tilt tests at the beginning and end of habituation. 3) Their blood pressure and heart rate will be recorded and the investigators will determine if there is a loss of low frequency (0.025 Hz) oscillations, which the investigators have found in animal models to disappear when the animals are habituated. 4) Habituation should be accompanied by an increase in heart rate to counteract the fall in blood pressure.
The purpose of the present clinical trial is to determine whether the use of an elastic abdominal binder is effective in the non-pharmacological management of symptomatic, neurogenic orthostatic hypotension (OH) in individuals suffering from Parkinson's disease (PD) or Parkinson variant multiple system atrophy (MSA-P).
Incidence of orthostatic intolerance and orthostatic hypotension after intravenous administration of morphine in patients prior to hip or knee arthroplasty.
This study looks to characterize autonomic nervous system dysfunction after spinal cord injury and identify the potential role that transcutaneous spinal cord stimulation may play at altering neuroregulation. The autonomic nervous system plays key parts in regulation of blood pressure, skin blood flow, and bladder health- all issues that individuals with spinal cord injury typically encounter complications. For both individuals with spinal cord injury and uninjured controls, experiments will utilize multiple parallel recordings to identify how the autonomic nervous system is able to inhibit and activate sympathetic signals. The investigators anticipate that those with autonomic dysfunction after spinal cord injury will exhibit abnormalities in these precise metrics. In both study populations, transcutaneous spinal cord stimulation will be added, testing previously advocated parameters to alter autonomic neuroregulation. In accomplishing this, the investigators hope to give important insights to how the autonomic nervous system works after spinal cord injury and if it's function can be improved utilizing neuromodulation.
Incidence and pathophysiologic hemodynamics of postoperative orthostatic intolerance and orthostatic hypotension in patients receiving antihypertensives
The objective of this study is to find a more objective and accurate way to assess the efficacy of the treatment for neurogenic orthostatic hypotension. For this purpose, the investigators will use an activity monitor to determine the amount of time patients spend in the upright position (standing and walking; upright time) during 1 week of placebo (a pill with no active ingredients) and 1 week of their regular medication for orthostatic hypotension (midodrine or atomoxetine at their usual doses). Total upright time (i.e. tolerance to standing and walking) will be compared between placebo and active treatment to test the hypothesis that it can be used to assess the efficacy of the treatment for orthostatic hypotension and whether this outcome is superior to the assessment of symptoms using validated questionnaires.
The purpose of this study is to learn more about the effects of abdominal compression and the medication midodrine, two interventions used for the treatment of orthostatic hypotension (low blood pressure on standing), on hemodynamic markers of cardiovascular risk. The study will be conducted at the Vanderbilt University Medical Center and consists of a screening and 2 testing days, one with abdominal compression and one with midodrine. The total length of the study will be about 5 days.
This study will comprise of two phases, an observational phase and a treatment phase. In the observational phase the specific aims are: 1. To determine the presence and regional distribution of microglial activation, as assessed by 18F-PBR06 PET, in subjects with MSA as compared to healthy controls, at baseline and at 6-9 months' follow-up. 2. To assess the relationship between microglial activation and clinical progression at baseline and follow-up. In the treatment phase the specific aims of the study are: The specific aims of the study are: 1. To assess whether verdiperstat (BHV-3241) reduces 18F-PBR06 PET signal, and thus microglial activation and inflammation, in well-characterized MSA patients. 2. To assess the relationship between PET changes and clinical progression at baseline and follow-up in patients treated with verdiperstat. 3. To assess the relationship between PET changes and volumetric brain MRI at baseline and follow-up in patients treated with verdiperstat. Currently there is no known disease modifying therapy for MSA. Recently, the drug verdiperstat (BHV-3241) has appeared in the investigational arena specifically for the indication of Multiple System Atrophy. Verdiperstat (BHV-3241) is currently being used in a phase 3 active drug trial at Massachusetts Hospital. Verdiperstat (BHV-3241) is known to target Myeloperoxidase, an enzyme implicated in neuroinflammation, a major driver in disease pathogenesis. Our previous study (IRB protocol #2016P002373) demonstrated that applying TSPO (translator protein) PET imaging enabled us to track changes in neuroinflammation and thus provide a viable biomarker for disease progression. In this pilot study, the investigators aim to assess the effect of an investigational drug, verdiperstat (BHV-3241) on microglial activation in MSA patients using [F-18]PBR06 and to link it with clinical and morphometric MRI brain changes following treatment.
The study is examining differences in central arterial stiffness, orthostatic changes in blood pressure, norepinephrine, and plasma renin in individuals with spinal cord injury compared with age-matched uninjured controls.
Orthostatic hypotension (OH), which consists in a significant reduction in blood pressure levels upon standing from a seated position, may affect approximately one in three patients with Parkinson's disease (PD). It usually presents as dizziness, lightheadedness, feeling faint, or feeling like you might black out while standing. This can significantly impact the quality of life (QoL) of PD patients, resulting in difficulties with balance, walking, and increased risk of falls. The main aim of this study is to evaluate whether the use of technological devices (a computerized system for analyzing abnormalities in walking in clinical settings and a wearable sensor to detect changes in postural unsteadiness in the home environment) may improve the detection of complications and the response to medical therapies for OH in patients with PD.