View clinical trials related to Cardiac Output.
Filter by:Cardiac output (CO) is an essential physiological parameter of healthy person or illness. In clinical practices, all methods of measuring the CO(Fick method, thoracic impedance, esophageal echodoppler etc) contain limit. Each method are dangerous or hard to implement. CO is probably determining element of blood transit time and thus the availability of oxygen between the central organs (heart, lung) and the peripheral organs (leg, arms). Our hypothesis is transcutaneous oxymetry mesurement with oxygen inhalation, to cause a transient hyperoxia, can be used to determinate blood transit time between central organs and peripheral organs. This simple method will be non invasive technique.
Shunt quantification in atrial septal defect (ASD) is estimated by Echocardiography-Doppler, with the pulmonary-to-systemic blood flow ratio: Qp/Qs. Higher is the ratio, more important is the shunt, and the consequence on right ventricular function. A value higher than 1.5 is one of the criteria for percutaneous closure of Secundum ASD. Maatouk and al. have demonstrated that a shunt fraction (Qp/Qs) over 3 is a predictive factor of an incomplete reversibility of the right ventricular remodeling [1]. Even if the accuracy of Doppler echocardiography is admitted for Qp/Qs measurement, there is still some technical difficulties. Thus, the right cardiac catheterization for O2 consumption measurement by the direct Fick method is used. The major inconvenient is the potential risk of adverse effects. Non-invasive methods have been developed using physical properties (as the thoracic bioimpedance) or inert gas rebreathing technique. Thoracic Bioimpedance (TB) and inert gas rebreathing (IGR) techniques have been studies on healthy individual and different respiratory or cardiac diseases to evaluate the cardiac output (CO). TB and IGR measure the systemic and pulmonary blood flow respectively. Without shunt the pulmonary blood flow is equal to the systemic blood flow. Thus, Investigator suppose that combine the two techniques in disease with shunt, will allow a quantification of the shunt fraction Qp/Qs as accurate as with the gold standard technique (Fick method and Echocardiography Doppler). The purpose of the study is to evaluate the feasibility and the accuracy of the non-invasive measurement of the Qp/Qs ratio in secundum ASD using the IGR technique and the TB versus the two gold standard techniques: the Fick method and the Echocardiography-Doppler. The study hypothesizes that the values of Qp et Qs determined by IGR et TB respectively are in the same range of values that the one determined by gold standard techniques.
Cardiac output, the amount of blood pumped by the heart in one minute, will be measured in pediatric patients undergoing surgery involving cardiopulmonary bypass (CPB). Cardiac output will be measured after cardiopulmonary bypass using a device that employs ultrasound dilution technology. At times, cardiac output will be measured during a procedure called modified ultrafiltration (MUF). The ultrasound dilution cardiac output measurements will be validated or compared with cardiac output measurements made using other FDA approved techniques and devices.
Cardiac output, the amount of blood pumped by the heart in one minute, will be measured in adults undergoing surgery involving cardiopulmonary bypass. Cardiac output will be measured before and after cardiopulmonary bypass using a device that employs ultrasound dilution technology. The ultrasound dilution cardiac output measurements will be validated or compared with cardiac output measurements made using thermodilution, which is the current "gold standard."
This study is to test the usefulness of ultrasound dilution measurements in patients on extracorporeal membrane oxygenation. Measurements may include; efficiency of support (recirculation), amount of clotting in the oxygenator (oxygenator blood volume), and how well the heart is working (cardiac output). At the present time there are no devices available to perform these functions.