Active clinical trials for "Hypotension"

The purpose of this study is to determine whether phenylephrine infusion are effective in the prevention of hypotension after changing position to beach chair position during general anesthesia for shoulder arthroscopic surgery. Investigators hypothesized that by increasing arterial blood pressure with phenylephrine infusion, incidence of hypotension would be decreased.

This study evaluates the effect of prophylactic ondansetron on the incidence of spinal hypotension and vasopressor consumption in caesarean section patients using norepinephrine treatment. Half of participants receive ondansetron before spinal anesthesia while the other half receive saline.

Pregnant women with a positive preoperative Supine stress test were found to be a subgroup at increased risk of symptomatic hypotension after spinal anesthesia

Subarachnoid block is the preferred method of anaesthesia for caesarean section, but is associated with hypotension and bradycardia, which may be deleterious to both parturient and baby. Animal studies suggest that in the presence of decreased blood volume, 5-HT may be an important factor inducing the Bezold Jarisch reflex via 5-HT3 receptors located in intracardiac vagal nerve endings. In this study, the investigators evaluated the effect of ondansetron, as a 5-HT3 receptor antagonist, on the haemodynamic response following subarachnoid block in parturients undergoing elective caesarean section.

The aim of this study is to evaluate the effect of leg elevation on the prevention of intraoperative hypotension during shoulder surgery in the Beach-chair position. patients undergoing shoulder surgery in the Beach-chair position will be randomly assigned to Group L (with leg elevation) or Group C (no intervention). The primary outcome is the incidence of intraoperative hypotension (mean blood pressure < 60mmHg or systolic blood pressure < 80% of baseline). Secondary outcomes are the incidence of intraoperative cerebral desaturation (cerebral oxygen saturation < 80% of baseline, longer than 30 seconds), total amounts of administered inotropic agents, and systolic blood pressure, heart rate, and cerebral oxygen saturation at various time points.

The purpose of this study is to determine whether a decision support system can improve the adherence to thresholds for low blood pressure by anesthesia providers, which in turn prevents their patients from having organ injury.

The prophylactic use of small doses of ephedrine may be effective in obtunding of the hypotension responses to propofol with minimal hemodynamic and ST segment changes. The investigators aimed to evaluate the effects of small doses of ephedrine on hemodynamic responses of propofol anesthesia for valve surgery. There is widespread interest in the use of propofol for the induction and maintenance of anesthesia for fast track cardiac surgery. However, its use for induction of anesthesia is often associated with a significant rate related transient hypotension for 5-10 minutes. This is mainly mediated with decrease in sympathetic activity with minor contribution of its direct vascular smooth muscle relaxation and direct negative inotropic effects. Ephedrine has demonstrated as a vasopressor drug for the treatment of hypotension in association with spinal and general anesthesia. Prophylactic use of high doses of ephedrine [10-30 mg] was effective in obtunding the hypotensive response to propofol with associated marked tachycardia. However, the use of smaller doses (0.1-0.2 mg/kg) was successfully attenuated, but not abolished, the decrease in blood pressure with transient increase in heart rate. This vasopressor effect is mostly mediated by β-stimulation rather than α-stimulation and also indirectly by releasing endogenous norepinephrine from sympathetic nerves. Because the effect of decreasing the dose of ephedrine from 0.1 to 0.07 mg/kg may be clinically insignificant, the investigators postulated that the prophylactic use of small dose of ephedrine may prevent propofol-induced hypotension after induction of anesthesia for valve surgery with minimal in hemodynamic, ST segment, and troponin I changes. The aim of the present study was to investigate the effects of pre-induction administration of 0.07, 0.1, 0.15 mg/kg of ephedrine on heart rate (HR), mean arterial blood pressure (MAP), central venous and pulmonary artery occlusion pressures (CVP and PAOP, respectively), cardiac (CI), stroke volume (SVI), systemic and pulmonary vascular resistance (SVRI and PVRI, respectively), left and right ventricular stroke work (LVSWI and RVSWI, respectively) indices, ST segment, and cardiac troponin I (cTnI) changes in the patients anesthetized with propofol-fentanyl for valve surgery.

A fall in blood pressure (hypotension) occurs in one third of spinal anesthetics administered to pregnant patients undergoing cesarean delivery. However, predicting which patients will experience hypotension following spinal anesthesia has proven difficult. Pulse wave analysis is a repeatable and reproducible method for investigation of cardiovascular function. A device called a SphygmacorTM can be used to measure pulse. The pulse measurement is called the Augmentation Index (AIx). AIx has been useful in detecting risks associated with blood pressure changes after complex surgery in patients with heart and blood vessel disease. In this study the investigators wish to see if it is possible to predict if a subject will experience hypotension based on her AIx measurement preoperatively.

The aim of the study is to evaluate the efficacy of Voluven® in the prevention of maternal hypotension in women undergoing spinal anesthesia for cesarean section

The purpose of this study is to determine the minimum effective bolus dose of phenylephrine to prevent post-spinal hypotension in Cesarean section in 95 % of our patients. An adequate response will be defined as the absence of hypotension or nausea/vomiting during the period from induction of spinal anesthesia to uterine incision prior to fetal delivery.