View clinical trials related to Circulatory Failure.
Filter by:It has been well established that only 40 to 60% of the patients hospitalized for inflammatory response syndrome (SIRS) positively respond to volume expansion (VE). The fluid responsiveness is usually estimated by assessing VE-induced change in stroke volume (SV). To guide prescriptions and possibly avoid deleterious effects of inappropriate VE, several clinical studies demonstrated that invasive dynamic indices based on heart-lung interactions permit an accurate prediction of the hemodynamic effects induced by VE. Mechanical ventilation induces cyclic changes in intrathoracic and transpulmonary pressures that transiently affect venous return, right and left ventricular preload, resulting in pronounced cyclic changes in SV in preload-dependent, but not in preload-independent patients. These cyclic changes in SV can be evaluated by the cyclic changes in arterial pulse pressure. Several studies have shown that pulse pressure variation is able to predict fluid responsiveness in patients in the operating room and intensive care unit (ICU). However, this technique requires percutaneous arterial catheterization, which is associated with several rare but serious complications (thrombosis, infections, pseudoaneurysm,hematoma, and bleeding). A method for assessing noninvasive arterial blood pressure using an electropneumatic control loop was introduced by Penaz in 1973. Briefly, the blood volume in a finger is measured and kept constant by applying corresponding external pressure. The continuously changing external pressure needed to keep the volume constant directly corresponds to the arterial pressure and, therefore can be used as continuous measurement of arterial blood pressure. Numerous studies evaluating the accuracy of this technology, e.g., Finapres™ (Ohmeda Monitoring Systems, Englewood, CO), and more recently of the Infinity CNAP™ SmartPod (Dräger Medical AG & Co.KG, Lübeck, Germany). The basic operating principle of the CNAP™ is similar to the Finapres™, but CNAP™ uses multiple control loops. It has recently been shown that CNAP provides real-time estimates of mean arterial blood pressure (MAP) comparable with those measured by an invasive intraarterial catheter system during general anaesthesia. The accuracy of the measures and the respiratory variations in pulse pressure obtained with the CNAP system have not yet been studied in ICU.
Objectives: To investigate whether respiratory variations of inferior vena cava diameters (cIVC) predict fluid responsiveness in spontaneously breathing patients with septic acute circulatory failure and irregular heartbeats. Design: Prospective, bicentric study, intensive care units. Patients and measures: Spontaneously breathing patients with sepsis and clinical signs of acute circulatory failure are included. A positive response to fluid loading (FL) is defined as an increase of the stroke volume (SV) >10%. The investigators measured the minimum inspiratory and maximum expiratory diameters of the IVC (idIVC and edIVC) during standardized (st) and unstandardized (ns) breathing. The investigators calculated cIVCst and cIVCns before a 500ml-colloid FL.
Hypovolemia and acute circulatory failure affects more than 60% of patients hospitalized in intensive care or resuscitation. The volume expansion (VE) by fluid replacement therapy is the first treatment improve circulatory function. However, too much VE can be harmful. So, the use of dynamic predictive indicators of fluid responsiveness is recommended in patients with sepsis.In patients with spontaneous ventilation, few studies have evaluated these parameters. In mechanical ventilation, indices based on the respiratory variation of the diameters of vena cava have been studied and validated to predict the response to VE. However there is no similar study in spontaneously breathing patients without ventilatory support. The investigators hypothesize that the respiratory variations in the IVC diameters and femoral artery flow during standardized respiratory cycles are predictive factors of fluid responsiveness in spontaneously breathing patients with sepsis, acute circulatory failure, and regular cardiac rhythm.
The study investigates the influence of a clinically indicated fluid challenge on end-expiratory lung impedance, assessed by electrical impedance tomography (EIT). EIT data will be collected before, during and after infusion of 500 ml of crystalloid solution in mechanically ventilated patients on an operative intensive care unit.
After a basic training to echocardiography, emergency physicians will have to answer simple clinical questions about circulatory failure mechanisms. The objective of the study is to assess the agreement between these answers and those of the expert physician in patients admitted in the emergency department with a circulatory failure due to sepsis or not. Emergency physicians will volunteer to take part in a basic training on echocardiography. The training will include 4 hours of theory, 2 hours of interactive clinical cases and 6 hours of tutored practice at patients' bedside (10 to 15 examinations). The objective of the practice sessions will be to learn the technical grounds of transthoracic echocardiography (TTE), the different views and to identify the anatomical structures. The second part of the study will start after the training. Each eligible patient will be successively assessed by two investigators: one emergency physician recently trained and the expert physician. The echocardiography will be performed as soon as possible in the emergency department before or after the initiation of treatment without delaying it. The order of hemodynamic assessments will be random depending on the availability of the investigators; both assessments will however be performed within 30 minutes. Each investigator will independently read the echocardiography in real time at patients' bedside. They will then answer a limited list of standardized questions using two-choice answers or predefined choices. Finally investigators will choose a therapeutic proposition among a predefined list based on the answers. Only the results of the echocardiography performed by the expert physician will be used in patient management.
Suspension syndrome refers to a potentially life-threatening condition that can occur in unconscious persons after prolonged suspension in a harness. To date, our understanding of the pathophysiology and appropriate treatment is based primarily on case reports and expert opinion. The main pathophysiological hypothesis implicates blood pooling in the lower extremity and lack of return via muscle pumping. However, a recent French study could not support this hypothesis. Other mechanisms, such as a central vagal reflex may play a role in the pathophysiology of suspension syndrome. The aim of this study is to better understand the pathophysiological basis of suspension syndrome and to develop practical recommendations for prevention and treatment.
Purpose: Fluid responsiveness in a context of circulatory failure can be predicted by different way. Dynamic criteria such as pulse pressure variation, stroke volume variation during an end-expiratory occlusion maneuver or a passive leg raising have been reported to predict fluid responsiveness. Only aortic velocity peak variation measured with transthoracic echocardiography during mechanical ventilation has been reported to predict fluid responsiveness in children. Besides some physician use a maneuver of abdominal compression to predict fluid responsiveness in children with circulatory failure. This strategy has never been formally evaluated. The investigators will study the diagnosis accuracy of the stroke volume variation induced by an abdominal compression to predict stroke volume variation after 10 ml/kg fluid load in children with circulatory failure. Thirty-eight pediatric patients under eight years old in circulatory failure, for whom the attending physician has decided a fluid load will be included. Hemodynamic parameters: arterial pressure, heart rate, stroke volume measured with echocardiography; will be recorded. This data collection will be performed before, after abdominal compression and after a fluid load of 10 ml/kg. Patients will be aposteriori sorted in two groups: Fluid responders and Fluid non-responders. Fluid responders are defined as patients that show an increase greater than 15 % in stroke volume. The diagnosis ability of the Stroke volume variation after an abdominal compression to predict fluid responsiveness will be investigate and receiving operative characteristic (ROC) curve will be built. The correlation between the variation of stroke volume during abdominal compression and during the fluid load will be studied. Other parameters such as arterial pressure and heart rate will also be investigated.
Fluid responsiveness in a context of circulatory failure can be assessed by different way. Microcirculatory evaluation to assess fluid responsiveness could be interesting, but the available device are expensive and the analysis are delayed. Capillary refill time (CRT) is hampered by its variability. The investigators have developed a method to standardize the pressure, the length of compression and a computerized analysis to calculate the capillary refill time. This method enables accurate measure of CRT. The investigators will study if CRT variation induced by a passive leg raising (PLR) can predict CRT after a 500 ml Fluid Load. About thirty patients in circulatory failure with a continuous cardiac output monitoring for whom, the attending physician has decided a fluid load, will be included. hemodynamic parameters (arterial pressure, venous pressure, cardiac output), metabolic parameters (arterial and venous blood gas and lactate), microcirculatory parameters (assessed by sublingual video-microscopy) and capillary refill time measured on the thorax and on the gingival area will be recorded. Data collection will be made before and after a passive leg raising and after a 500 ml fluid load of crystalloids. Patients will be aposteriori sorted in two groups: responders and non responders, defined by the reduction of CRT after the fluid load. The diagnosis ability of the CRT variation after PLR to predict in which group each patient is classified will be investigate and receiver operative characteristic curve will be built. These results will be compared to the metabolic response, the macrocirculatory response, and the microcirculatory response.
Our goal was to study the feasibility of predicting fluid responsiveness by transcutaneous partial pressure of oxygen (PtcO2) in the critically ill patients.
1 in 1000 babies are born suffering from a lack of oxygen. This is known as hypoxic ischemic encephalopathy (HIE). Infants with this condition can suffer multiple organ problems. In particular it can affect how their hearts pump blood around their body thus leading to a poor blood supply to parts of their body such as the brain. This is known as circulatory failure and can contribute to poor long term outcomes such as cerebral palsy. To try and prevent brain damage these infants are treated with total body cooling, however this treatment can further effect how babies pump blood around the body, but also how drugs which may be used by in this condition are processed. In order to assess and treat this condition doctors need to be able to accurately measure the blood supply in an infant. However there is no agreement on how best to do this. This makes decisions about when to treat an infant difficult. Sometimes doctors may want to use drugs such as dobutamine or adrenaline but these drugs are unlicensed in babies. This study proposes to observe the way babies circulatory problems are treated in babies with HIE the in the first four days of life. In addition the study will look are two new measurements of a babies blood supply to see if they are a better measure of when an infant needs treatment. This will involve an ultrasound scan of the heart and measurement of the baby's oxygen levels from a probe placed on their hand. The study will also look at how the drug dobutamine is processed by babies. This will be done from two small extra blood tests. The aim of the study is to help clinicians refine the identification and treatment of circulatory failure in babies with HIE.