View clinical trials related to Hypotension.
Filter by:Background: - Orthostatic hypotension is a fall in blood pressure when standing up. Normally, a reflex action of the automatic nervous system makes blood vessels tighten when people stand up. The nervous system releases the chemical norepinephrine, which tightens blood vessels and keeps blood pressure in check. In orthostatic hypotension, the nervous system does not release enough norepinephrine when a person stands up, which can cause fainting or falling. Researchers are interested in determining whether norepinephrine given as a drug by vein can help maintain blood pressure during changes in body position. Objectives: - To determine whether intravenous norepinephrine can maintain blood pressure in people with orthostatic hypotension. Eligibility: - Individuals at least 18 years of age who have been diagnosed with orthostatic hypotension related to Parkinson's disease or pure autonomic failure. Design: - This study will require a 2-day inpatient admission to the NIH Clinical Center. The first day will involve laboratory evaluation and the second day will involve testing with norepinephrine. The second day requires an overnight stay. - Participants will be screened with a medical history and physical examination, blood samples, and an electrocardiogram or echocardiogram. - Participants who are on medications may be asked to taper or discontinue one or more medications for the purposes of this study. Participants may not take aspirin or any drugs that slow blood clotting for 7 days before study participation. - Day 1: Participants will have a clear liquid breakfast, and will have a 1-hour baseline tilt table test to monitor blood flow, skin temperature, sweating, and blood pressure. Body temperature and breathing will also be monitored. - Day 2: Participants will have a clear liquid breakfast, and will have a 2-hour tilt table test. Initial blood pressure readings will be taken, and an intravenous line will be placed. Participants will then receive norepinephrine or saline, followed by additional position changes of the tilt table to measure blood pressure differences before returning to the starting position. After about 10 minutes, the tilt table testing and infusion will be repeated with the other drug (saline or norepinephrine). - Participants will be discharged 24 hours after the testing is complete.
This study aims to identify women at risk of low blood pressure (hypotension) after the usual cesarean anesthetic - a spinal anesthetic. Hypotension may be caused by dehydration. We believe we can predict who will get hypotension by using two anesthesia monitors together with a passive leg raise (PLR) (legs elevated after a period spent reclining). The PLR will cause a shift of blood from the legs to the heart, and the monitors will detect the heart's response to tell if a subject is dehydrated. We want to see if these dehydration tests can also predict hypotension after a spinal anesthetic.
To determine if proprietary software that uses pulse-wave analysis to interpret the output of a conventional pulse-oximeter, can predict the onset of circulatory stress, before changes in blood pressure and pulse occur, in patients undergoing outpatient hemodialysis.
The purpose of this study is to assess if abdominal binders that use pull strings to adjust compression (non-elastic) are more effective than standard elastic abdominal binders in attenuating neurogenic orthostatic hypotension.
1. Aim: The aim of the clinical trial is to study the accuracy of the TensorTip device compared with registered (FDA-approved) invasive and non-invasive devices. 2. Hypothesis: Human physiological biomarkers may be measured from the color distribution of the internal or external (skin) tissue. The technology of the TensorTip finger-mounted device is based on the color distribution of the peripheral blood tissue, which enables the measurement of certain biomarkers and vital signs under consideration.
This is a study to evaluate the effects of an investigational drug, Droxidopa, in participants with neurogenic orthostatic hypotension (NOH), associated with Parkinson's disease. Droxidopa is being studied to determine the effects on blood pressure changes upon standing up (orthostatic challenge). Symptoms and activity measurements, including patient reported falls, will be evaluated to determine the effectiveness of the study drug. Symptoms of NOH may include any of the following: - Dizziness, light-headedness, feeling faint or feeling like you may blackout - Problems with vision (blurring, seeing spots, tunnel vision, etc.) - Weakness - Fatigue - Trouble concentrating - Head & neck discomfort (the coat hanger syndrome) - Difficulty standing for a short time or a long time - Trouble walking for a short time or a long time The study duration is a maximum of approximately 14 weeks including up to 2 weeks for screening, up to 2 weeks for proper dose finding, followed by an 8 week treatment period and a follow-up visit after 2 weeks. A sufficient number of patients will be screened to allow approximately 211 randomized patients. An extension study is also available to continue treatment if determined appropriate by the study doctor. This Study is NCT01132326 sponsored by Chelsea Therapeutics and is enrolling by invitation only.
Hypotension after spinal anesthesia for Cesarean section occurs in up to 90% usually under five minutes after local anesthetics administration. These changes are poorly depicted by oscillometric measurements. The investigators hypothesized, that a continuous noninvasive device detects more hypotensive periods with lower blood pressures.
One purpose of this study is to determine if taking droxidopa after eating will have an effect on how the body processes (absorbs and eliminates) the drug in healthy elderly subjects. Another purpose of this study is to see how the body processes (absorbs and eliminates) one 300mg capsule compared to three 100mg capsules. This study will also evaluate how well the body processes (absorbs and eliminates) and tolerates droxidopa when a 300 mg capsule is given 3 times a day for a total dose of 900 mg over the course of one day. Droxidopa is used to treat low blood pressure upon standing in patients with diseases of the nervous system, to prevent low blood pressure in patients with kidney disease during hemodialysis (removal of waste products of the blood), and to treat frozen gait (walking, stepping or running) and dizziness upon standing in patients with Parkinson's disease.
Hypotension frequently occurs during anesthesia induction. Preload decrease by anesthetics was often considered as one of main causes for this hypotension. However, the studies on this topic have been lacking. Dynamic preload indices are more suitable than static preload indices to predict the effect of preload changes. And, recently, passive leg raising test showed successful results to predict fluid responsiveness in patient with spontaneous ventilation. The investigators hypothesized that hypotension after induction of anesthesia is caused by decrease of preload by anesthetics and passive leg raising test could predict this hypotension. In this study, the investigators will try to evaluate whether passive leg raising induced hemodynamic changes could predict hypotension during anesthesia induction.
Symptomatic NOH in patients with primary autonomic failure is thought to be a consequence of norepinephrine depletion leading to a diminished capacity to effect an appropriate cardiovascular response to an orthostatic challenge resulting in symptomatic cerebral-hypoperfusion. Droxidopa augments norepinephrine levels which should lead to improved cerebral perfusion following orthostatic challenge thereby reducing the symptoms of NOH. The present study will evaluate the long-term safety of droxidopa.