ABSTRACT
Cardiac output (CO) is defi ned as the volume of blood ejected from the left ventricle per minute. It is determined by a number of interplaying factors including heart rate, rhythm, preload, contractility and afterload. Circulation (both in terms of pressure and fl ow) is essential to organ perfusion and O2 delivery. However, it varies signifi cantly under different physiological extremes and disease states.
