View clinical trials related to Hypotension.
Filter by:Rapid administration of crystalloid immediately after induction of spinal anesthesia (coload) to be more effective in terms of managing hypotension as compared to administering crystalloid before spinal anesthesia (preload). Phenylehrine infusion is a safe and effective way to reduce incidence and frequency of hypotension during SA for cesarean delivery. Hypotension was virtually eliminated by use of high-dose prophylactic phenylephrine infusion at a rate of 100 µg/min and rapid crystalloid coload up to two liters (administration at the time of SA). However, incidence of reactive hypertension was frequent up to 47% with decrease in maternal heart rate (HR). This may raise concern in patients in whom increase of blood pressure may be detrimental, like chronic hypertension and in the presence of a compromised uteroplacental blood flow. A recent study found that infusing phenylephrine at a fixed rate of 75 and 100 ug/min is associated with more episodes of hypertension than placebo or the lower infusion rates of 25 and 50 ug/min respectively. However, there was no reduction in the number of physician interventions (phenylephrine boluses and stopping the infusion) needed to maintain maternal systolic blood pressure within 20% of baseline among all groups. Prophylactic fixed rate infusions may have limited application in clinical practice, and a variable rate (i.e. modifying the rate according to hemodynamics) has been advocated. The bolus administration of phenylephrine to treat hypotension is still commonly used, but requests multiple interventions from the anesthesiologists and is time consuming. Eighty patients scheduled for cesarean delivery under spinal anesthesia will be assigned to one of two groups. Immediately after spinal injection, rapid crystalloid colaod of lactated Ringer of 15 mL/kg over a period of 10-15 min will be initiated. Patients in Group I will receive infusion of normal saline (placebo) and patients in group II variable infusion rate of phenylephrine started at 0.75 ug/kg (close to the dose of 50 ug/min recommended for fixed infusion rate). The number of interventions needed to maintain maternal systolic blood pressure within 20% of baseline, hemodynamic performance, intraoperative nausea and vomiting, and umbilical cord blood gases will be compared between the two groups. We will define a reliable and safe method to ensure maternal hemodynamic stability during spinal anesthesia for cesarean delivery with the least physician interference.
This study is being done to study the combination of pyridostigmine and low-dose Droxidopa for the treatment of orthostatic hypotension.
In this study the investigators aimed 1. to investigate the prevalence of orthostatic hypotension in elderly nursing home residents. 2. to investigate whether the presence of orthostatic hypotension influences the chance of successful rehabilitation.
The investigators seek to determine the efficacy, duration of action and safety of escalating dose of droxidopa on systemic blood pressure, cerebral blood flow and vasoactive hormones and catecholamines during upright seated posture. Primary Question: 1. What is the lowest dose of droxidopa that increases seated SBP to 115±5 mmHg in men and 105±5 mmHg in women? - When does the defined increase in SBP occur after oral ingestion of droxidopa? - How long does this dose of droxidopa sustain SBP at these levels? - What are the vital signs and the subjective symptomology following droxidopa administration? Secondary Question: 1. What is the MFV response to droxidopa administration in hypotensive individuals with SCI? - Does an increase in SBP correspond to an increase in MCA MFV? Tertiary Question: 1. What is the vasoactive hormone and catecholamine response to droxidopa administration in hypotensive individuals with SCI? - Does droxidopa administration result in a change in APR, Aldo or NE in hypotensive individuals with SCI?
Ascites is a frequent complication of patients with portal hypertension. As portal hypertension progresses, a percentage of these patients develop refractory ascites. Management options at that point include either TIPS or intermittent large volume paracentesis (LVP), with its attendant risks, Portal hypertension is accompanied by systemic circulatory dysfunction (decreased systemic vascular resistance and systolic BP), which is exacerbated by large volume paracentesis, with resultant renal and cardiac dysfunction. There are limited options for managing patients with acute decompensation, such as hepatorenal syndrome, although midodrine and other vasoconstrictors have been used in such patients. Midodrine has not been used as a possible therapeutic for ascites. Midodrine however, has been found to change the hemodynamics related to portal hypertension and ascites. There has been also change in mediators related to renal and circulation in studies of short duration (7 days) but not found in studies of 1 month duration, however the clinical effects of midodrine is found for longer duration in other similar conditions. The purpose of the study is to assess the utility of midodrine in patients with obvious systemic circulatory dysfunction (hypotension) in improving the outcome of patients with refractory ascites and change in hemodynamic parameters and its mediators. Specific endpoints include: 1) an objective reduction of the volume/rate of accumulation of ascites and 2) a decrease in the frequency of LVP.
Low blood pressure or hypotension is a very important problem that is often seen in premature babies, especially those with low birth weight. Severe hypotension leads to significant problems including brain bleeds, developmental delays, kidney and liver problems, and other issues that can affect babies for the rest of their lives. An important aspect in the management of infants with hypotension is the decision of when to treat and with what agent. Research is being conducted to try to find the best medication to use in these situations. Dopamine is often used first, but it does not always prove to be effective, and it has several concerning side effects. This study will look at vasopressin, which has fewer side effects, as a first-line medication for low blood pressure in extremely low birth weight infants. Hypotheses and Specific Aims: This study will show superiority of vasopressin to dopamine in preterm, extremely low birth weight infants who have hypotension within the first 24 hours of life. We will specifically look at its ability to raise blood pressure values, improve clinical symptoms seen, any adverse effects, and clinical outcomes of babies being treated.
The autonomic or automatic nervous system helps control blood pressure. Diseases of the autonomic nervous system may result in a drop in blood pressure on standing in many cases leading to fainting. Diseases that affect the autonomic nervous system include pure autonomic failure, multiple system atrophy and Parkinson's disease, and can present with very similar symptoms and it is sometimes difficult to determine an exact diagnosis. The purpose of the study is to find out if the blood pressure response from taking a single dose of the medication atomoxetine can help in the diagnosis of these diseases.
The purpose of this study is to determine whether the orthostatic hypotension reported among subjects during bortezomib-containing regimen is caused by a dysfunction of the autonomic nervous system (ANS).
Inadequate identification of and subsequent delayed therapy for patients with hypoperfusion (including hypovolemia, congestive heart failure and sepsis) is a common problem faced by physicians and intensivists caring for critically ill patients. Bedside clinical assessment is notoriously inaccurate in diagnosing complex etiologies of hemodynamic disturbances and in deciding on the appropriate therapy. Invasive techniques which are often required to guide diagnosis and therapy have significant risks associated with them, are costly, and are time consuming. New technology has been developed that allows for instantaneous, noninvasive monitoring of key hemodynamic parameters, like stroke volume, peak velocity and cardiac output. This new technology has the potential to improve recognition of the etiology of hemodynamic disturbances and assist the clinician in optimizing therapy based on changes in hemodynamic parameters. There is significant potential for this to be translated into improved outcomes in critically ill patients, but this has never been studied.
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.