Active clinical trials for "Hypotension"

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.

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.

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.

Spinal anesthesia is still the regional anesthesia technique most widely employed in everyday clinical practice. The most feared and common of its well known side effects consist in an abrupt reduction of systemic vascular resistances, with consequence risk of systemic hypotension. To prevent this potentially severe complication, an adequate correction of patients' volume status through a preventive administration of fluids is widely used. However this volume repletion is commonly accomplished on an empirical basis, without having a real insight of patient hemodynamic status, carrying the risk of possible volume overload. Aim of the study is to test the clinical impact of two simple, non-invasive methods to guide volemic repletion before spinal anesthesia on the reduction of significant hypotension rate, compared to empirical fluid administration.

The investigators hypothesize that given prophylactically, intravenous ondansetron will attenuate the drop in blood pressure and heart rate frequently seen after spinal anesthesia. Eighty-six American Society of Anesthesiologists (ASA) physical status I or II in preoperative patient assessment, parturients age of 18 to 45 years scheduled to undergo elective caesarean section will be enrolled. Patients will be randomized to 2 groups: the ondansetron group, receiving 8 mg intravenous ondansetron diluted in 10 mL of saline; or the placebo group, who were administered 10 mL of saline given 5 minutes prior to performing the spinal anesthetic. Investigational Pharmacy will randomize and dispense study drug. Baseline measurements of vital signs will be taken. Otherwise standard management will then be used: Patients must be NPO for 8 hours Pulse oximetry, EKG monitoring, noninvasive blood pressure at a minimum of every 3 minutes, more frequently if decided by the provider. Standard lumbar puncture in a sitting position the L3-L4 or L4-L5 Whitacre pencil-point, 25 gauge Injectate: 2 mL of 0.75% hyperbaric bupivacaine, 100 mcg preservative free morphine, 20 mcg fentanyl Immediately after completing the subarachnoid injection, patients will be laid supine with left lateral uterine displacement The sensory level of anesthesia will be assessed in the standard fashion every five minutes using ice. The motor component will tested using the Bromage scale for spinal anesthesia (0, no paralysis; 1, inability to lift the thigh [only knee/feet]; 2, inability to flex the knee [only feet]; 3, inability to move any joint in the legs).

This study was conducted to evaluate the effects of rapid crystalloid (Lactated Ringer's solution) or colloid (hydroxyethyl starch; HES) cohydration with a second intravenous access line on the incidence of hypotension and ephedrine requirement during spinal anaesthesia for caesarean section.

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 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.

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.