View clinical trials related to Cardiac Output.
Filter by:Hemodynamic monitoring, especially cardiac output assessment, is a key feature for the management of critically ill patients. Although the use of invasive methods, such as thermodilution with a pulmonary artery catheter, remains the GOLD standard for the evaluation of the cardiac output, several non-invasive techniques are currently used in practice. An acceptable estimation of the cardiac output can be made by standard transthoracic echocardiography. Cardiac output can be calculated from subaortic velocity time integral (VTI). However, this technique requires a trained operator and depends on the echogenicity of the patient. The best method for assessing cardiac output depends on the patient's needs, the clinical scenario and the physician's experience with the monitoring device itself. No simple and rapid tool currently exist for assessing cardiac output in critically ill patients. The measurement of end-tidal carbon dioxide (EtCO2) used in routine in critically ill patients requiring mechanical ventilation could be an interesting alternative. Indeed, the amount of carbon dioxide (CO2) exhaled depends on the production of CO2 by the body, the pulmonary blood flow (corresponding to cardiac output) and its elimination by alveolar ventilation. In controlled ventilation, ie for constant alveolar ventilation, EtCO2 should therefore depend only on cardiac output. It has been shown in a porcine model that EtCO2 and cardiac output are strongly related under stable respiratory and metabolic conditions. In humans, only the variation of EtCO2 after volume expansion has been studied and EtCO2 seems to reflect changes in cardiac output. Nevertheless, the usefulness of EtCO2 in assessing cardiac output has never been evaluated. The objective of this study is therefore to determine the relationship between EtCO2 and cardiac output evaluated by the measurement of subaortic VTI in critically ill patients.
To compare the less invasive Oesophageal Doppler cardiac output Monitor (ODM) to the invasive (standard of care) Transpulmonary Thermodilution cardiac output monitor (TPTD) in children.
Compromised peripheral tissue oxygenation during surgery may lead to worse patient outcome, mainly due to post-operative infections or heart failure. Insufficient stroke volume and/or cardiac output due to hypovolemia or cardiac defects play a central role in causing poor peripheral tissue oxygenation. In order to assess stroke volume, there are numerous invasive and non-invasive methods available. Up to the present date it is unknown, if these methods may by used interchangeably in patients with severe cardiac defects like aortic stenosis.
Recent occurrence of significant post-operative liver impairment at Nottingham University Hospitals NHS Trust has prompted investigation into whether interaction between general anaesthesia and prone positioning (lying face down) for surgery can influence liver function. Historical research has shown that the heart does not function as efficiently when an anaesthetised patient is placed in the prone position for surgery. The techniques used for anaesthetising and monitoring these patients have changed remarkably, since these studies were first performed. It is important to know accurately how the heart functions to enable better understanding of the changes in blood flow to the liver when in the prone position. Studies looking at blood flow to the liver when lying face down have been done before but are mainly reporting patients on the intensive care unit. These intensive care patients are different to those in theatre undergoing routine surgery. The intensive care patients are usually received in different types of drugs and monitored with several different types of monitor at the time. Perhaps most importantly is that they are placed face down on a soft air cushioned mattress and pillows rather than the rigid support used for surgical patients. This study will look at whether the function of the liver changes when a patient is anaesthetised and is then rolled onto their front. The function of the liver will be measured by looking how it clears a specific drug from the blood. Also this study will look at how accurate a particular type of heart monitor is when an anaesthetised patient is placed onto their front.