View clinical trials related to Hypotension.
Filter by:The purpose of this study is to compare two different strategies of intraoperative mean arterial pressure (MAP) and stroke volume index management in high-risk patients undergoing major abdominal and orthopedic surgery (manual versus automated) The investigators hypothesis is that the automated group will spend less time during surgery in hypotension (defined as a MAP<90% of patient's MAP baseline) compared to the manual group.
This study evaluates the volume of optimal resistance exercise to generate postexercise hypotension after performing a single exercise in hypertensive elderly subjects. 20 subjects will perform 1 control session and 3 resistance training sessions with different volume: 3, 6 and 9 sets
Spinal anesthesia for caesarean section is associated with a decrease in systemic vascular resistance and cardiac output and may cause hypotension in a significant portion of the parturients. Hypotension during delivery may cause maternal and fetal complications. If parturients who are likely to develop hypotension after spinal anesthesia can be identified before surgery, anesthesiologists would have opportunity to take measures such as prophylactic vasopressor administration. Perfusion index (PI) measured by pulse oximetry reflects vasomotor tone which affects the degree of hypotension after spinal anesthesia. This is a non-invasive method of assessing the relative vascular tone with the use of pulse oximeter which calculates the ratio of pulsatile versus the non-pulsatile component of the blood flow. A lower PI indicates greater peripheral vasomotor tone. Pleth variability index (PVI) is calculated using maximum and minimum values of perfusion index during respiratory cycles. PVI is one of the dynamic indices that can predict fluid responsiveness. There are several studies investigating the predictive value of finger PI and PVI on hypotension after spinal anesthesia. However the aortocaval compression by the gravid uterus directly effects the lower extremity perfusion. So, in this study we aimed to investigate whether the right toe PI and PVI values at supine and left lateral positions can predict hypotension during caesarean section.
The present study is aimed at comparing different strategies of UF profiling, dialysate sodium individualization and sodium profiling (even combining one with the other) and at evaluating the effectiveness of a new UF profile which has an ascending/descending shape. The goal of the study is to provide better dialysis tolerance and lower rates of intradialytic hypotensive events by the application of this UF profile design in combination with a neutral sodium balance.
Open label, randomized, cross-over clinical study comparing the acute effect of high versus low protein meals during dialysis on intradialytic blood pressure, 24-hour ambulatory blood pressure and arterial stiffness indices on maintenance hemodialysis patients.
Intraoperative hypotension is common in non cardiac surgery. longer duration of intraoperative hypotension is related with postoperative morbidity and mortality. however, with the change of hypotension criteria, the duration threshold also change. the relationship of different hypotension criteria and its duration is unclear. This study is to explore the their relationship.
The purpose of this study is to compare the administration of two different doses of ondansetron to placebo to prevent hypotension and bradycardia following spinal anaesthesia. Apart from haemodynamic parameters (blood pressure and heart rate),characters of the spinal blockage (time of onset and regression) will be recorded too.
This study will be collecting data on participants undergoing lower body negative pressure (LBNP) to simulate progressive blood loss. The goal of the study is to collect data to allow for development of an algorithm with machine learning to predict blood pressure responses to hyporvolemia by analyzing the arterial waveforms collected during LBNP.
Despite being studied less than half as frequently, autonomic dysfunction is a greater priority than walking again in spinal cord injury. One autonomic condition after spinal cord injury is orthostatic hypotension, where blood pressure dramatically declines when patients assume the upright posture. Orthostatic hypotension is associated with all-cause mortality and cardiovascular incidents as well as fatigue and cognitive dysfunction, and it almost certainly contributes to an elevated risk of heart disease and stroke in people with spinal cord injury. In addition, autonomic dysfunction leads to bladder, bowel, sexual dysfunctions, which are major contributors to reduced quality and quantity of life. Unfortunately, the available options for treating this condition, are primarily limited to pharmacological options, which are not effective and are associated with various side effects. It has been recently demonstrated that spinal cord stimulation can modulate autonomic circuits and improve autonomic function in people living with spinal cord injury. Neuroanatomically, the thoracolumbar sympathetic pathways are the primary spinal cord segments involved in blood pressure control. Recently, a pilot study has been published demonstrating that transcutaneous spinal cord stimulation of thoracolumbar afferents can improve cardiovascular function. However, some studies have shown that lumbosacral transcutaneous spinal cord stimulation can also elicit positive cardiovascular effects. Therefore, there is no consensus on the optimal strategy in order to deliver transcutaneous spinal cord stimulation to improve the function of the autonomic system, and it may be that lumbosacral (i.e. the stimulation site being used most commonly for restoring leg function is sufficient). Another key knowledge gap in terms of transcutaneous spinal cord stimulation is whether or not the current is directly or indirectly activating these spinal circuits. Last but not least, the effects of epidural spinal cord stimulation on the function of cardiovascular, bladder, bowel and sexual system in spinal cord injury have been investigated in no study yet. AIMS AND HYPOTHESES: Aim 1. To examine the effects of short-term (one session) transcutaneous spinal cord stimulation on the frequency and severity of episodes of orthostatic hypotension/autonomic dysfunction, and bladder, bowel, and sexual functions. These effects will be compared at two sites of stimulation. Hypothesis 1.1: Short-term transcutaneous mid-thoracic cord stimulation will mitigate the severity and frequency of orthostatic hypotension/autonomic dysfunction. Hypothesis 1.2: Lumbosacral transcutaneous spinal cord stimulation will improve bladder, bowel, and sexual functions. Aim 2. To examine the effects of long-term (one month) transcutaneous spinal cord stimulation on the severity and frequency of orthostatic hypotension/autonomic dysfunction. Hypothesis 2.1: Long-term stimulation of the mid-thoracic cord will result in sustained improvements in mitigated severity and frequency of orthostatic hypotension/autonomic dysfunction that is not dependent on active stimulation. Hypothesis 2.2: Long-term lumbosacral transcutaneous spinal cord stimulation will result in sustained improvements in bowel, bladder, and sexual function that is not dependent on active stimulation. Aim 3: To examine the effects of short-term (one session) epidural spinal cord stimulation on the severity and frequency of orthostatic hypotension/autonomic dysfunction, and bladder, bowel, and sexual functions. Hypothesis 3.1: Epidural spinal cord stimulation will mitigate the severity and frequency of orthostatic hypotension/autonomic dysfunction and improve bladder, bowel, and sexual function. Hypothesis 3.3: There is no significant difference between immediate effects of lumbosacral transcutaneous spinal cord stimulation and epidural spinal cord stimulation on bladder, bowel, and sexual function. For aim 1, 14 participants with spinal cord injury and no implanted electrodes on the spinal cord will be recruited. Participants will randomly receive one-hour stimulation under each of the two stimulation conditions in a crossover manner: Mid-thoracic and Lumbosacral. For aim 2, 28 individuals with spinal cord injury and no implanted electrode will be pseudo-randomized (1:1) to one of two stimulation sites. Participants will receive one-hour stimulation, five sessions per week for four weeks. Cardiovascular and neurological outcomes will be measured before the first stimulation session and after the last stimulation session. For aim 3, 4 participants with spinal cord injury with implanted electrodes on the spinal cord will be recruited to study the immediate effects of invasive epidural spinal cord stimulation. All outcomes will be measured in two positions: a) Supine, b) ~ 70° upright tilt-test. Additionally, bowel, bladder, and sexual functions in project 2 will be assessed weekly.
The investigators study 160 patients undergoing spinal surgery.Participants will be randomly divided into study group and control group.The study group will receive controlled hypotension by nitroglycerin and be divided into 3 groups according to CI.