Cardiac output has always been a subject of interest to both clinicians and researchers in different branches of medicine and surgery. In the last decade more attention has also been paid to its application in pediatrics, neonatology, fetal medicine and pregnancy. Better understanding of the peripheral circulation has provided more insight into the patholophysiology of different diseases. Many cardiac and non-cardiac disorders affect cardiac outputs. Monitoring of the changes in cardiac output is also important in the acutely ill patient. There are several methods to measure cardiac output,...