Dawn Simulation and Postural Hypotension
Orthostatic HypotensionOne of the most physiologically demanding things that older people do every day is to get up in the morning. After spending a night laying flat, where the blood distributes evenly across the body, when they stand in the morning (and the blood rushes to their feet), their cardiovascular system may not be able to compensate and maintain blood flow to the brain. This phenomenon is known as orthostatic or postural hypotension. The investigators have found in a group of young individuals that use of a dawn-simulation light that gradually wakes the brain is able to increase cardiovascular tone prior to arising. The goal of this experiment is to determine whether this dawn simulation light is able to increase cardiovascular tone in older adults such that they would have reduced or absent postural hypotension when they awaken in the morning. This would greatly reduce the risks of falls and their associated morbidities in older adults.
The Pleth Variability Index and Hypotension at Caesarean Under Spinal.
Caesarean SectionDuring a caesarean section the blood pressure is usually measured every few minutes and it may fall too quickly to be detected in a timely fashion by this intermittent means. The monitor the Masimo Rainbow SET® (MRS) uses a peg attached to a finger to detect (amongst other things) the flow of blood through it. One of the measures it takes is called the Pleth Variability Index (PVI) which (unlike standard blood pressure measurement) it measures continuously. The investigators would like to try the MRS on patients to see if the PVI can be used to predict falls in blood pressure.
Assessment of Hand-grip in the Prevention of Postural Orthostatic Hypotension
Orthostatic HypotensionThe study is aimed to assess the efficacy of hand-grip in preventing orthostatic hypotension in 20 patients diagnosed with autonomic failure. Five healthy subjects will be studied for comparison. The investigators will evaluate the subjects while on tilt table for 10 minutes and than while mounted from lying down to 70 degrees for additional 10 minutes. Blood pressure, heart rate and symptoms will be continuously measured. First study will evaluate the blood pressure changes. Second measure will include hand-grip maneuver 1 minute before the erect positon. Trans cranial Doppler will assess the intracranial blood flow during the position changes.
Prospective Trial of Alerting to Extended Hypotensive Exposures on Long-Term Outcome After Surgery...
AnesthesiaHypotensionPatients undergoing anesthesia for non-cardiac surgery will be randomized to either having their anesthesia team alerted or kept blinded to extended periods of less than normal blood pressure with the goal of studying if providing these alerts leads to improved outcome after surgery (lower risk of death or complication in the days and weeks following surgery).
A Study Comparing Two Spinal Techniques for for Cesarean Delivery Anesthesia
HypotensionHeadacheThe purpose of this study is to compare single shot versus sequential bolus spinal technique via a catheter in patients undergoing Cesarean Section. We aim to determine which technique results in less blood pressure reduction and subsequent vasopressor use. Other study endpoints include the incidence of maternal post dural puncture headaches and nausea and vomiting. In addition blood and CSF will be collected to see if biochemical mediators are related to wound hyperalgesia and healing.
Epidemiology of Septic Shock in Medical or Polyvalent ICU in the North-East Region of France
Severe SepsisPersistent HypotensionThe epidemiology of this study aims and outcome of patients with septic shock in the intensive care unit (or versatile) of the North-East region in france as well as the modalities of care.
Maternal Hypotension During Cesarean Section and Short Term Neonatal Outcome.
Elective Cesarean SectionMaternal HypotentionAbout 20-25% of deliveries are by cesarean section. Most are elective with use of regional anesthesia (spinal/epidural). Drop of blood pressure after regional anesthesia is common. It have the risk of reduction of blood flow to the placenta and the fetus. No studies had followed the newborns their first days of live,of mothers who developed hypotension in durins CS.
Non-invasive Objective Assessment of Hemodynamics in Preterm Neonates
Hypotension and ShockHypoperfusion4 moreStudy type: Prospective Observational trial Study design: Longitudinal Population: Preterm newborns <32 weeks gestational age Hypothesis: The inclusion of non-invasive physiological measures of cardiac output, peripheral perfusion and brain oxygenation (NIRS) for preterm neonates is feasible and reveals additional information on the hemodynamic status compared to blood pressure alone. These measurements can improve the ability to rapidly identify those infants who might benefit from intervention and are correlated with short term clinical outcomes.
Effect of Phenylephrine Versus Norepinephrine on Venous Return
Arterial HypotensionInduction of general anesthesia often induces a decrease in the mean arterial blood pressure (MAP) caused by arterial and venous dilatation. Fluid administration is conventionally used to increase the patient's total blood volume, but is often associated with multiple adverse events such as postoperative edema. Arterial hypotension can also be treated by vasopressor agents such as norepinephrine and phenylephrine which mainly increase the blood pressure by arterial vasoconstriction. Compared to phenylephrine, norepinephrine has a shorter half-life (2 - 3 minutes) and improves the MAP by increase in cardiac contractility. In a recent study at our department it was demonstrated that besides arterial vasoconstriction, phenylephrine also improves venous return and cardiac output by venous vasoconstriction. The aim of this study is to compare the hemodynamic effects of both vasopressor agents in patients undergoing deep inferior epigastric perforators (DIEP) flap surgery. If significant differences between both agents are demonstrated, these findings can provide an important basis for future recommendations.
Neurohumoral Mechanism of Deferent Frequency Transcutaneous Electrical Acupoint Stimulation(TEAS)...
HypotensionThe purpose of this study is to explore the neurohumoral mechanism of deferent frequency TEAS pretreatment.