Figure 52-12 Schematic drawing of the circulation. Compliant regions (stippled lines) of the upper and lower parts of the body and end-diastolic volumes of the left ventricle in a control state (left panel) are shown after occlusion of aorta alone (middle panel) and combined occlusion of the aorta and inferior vena cava (right panel). IVC, inferior vena cava; LV, left ventricle; PVS and PVI, pressure in compliant regions of the upper and lower body respectively; Shunt, physiologic shunt; SVC, superior vena cava. (From Stokland O, Miller MM, Ilebekk A, Kiil F: Mechanism of hemodynamic responses to occlusion of the descending thoracic aorta. Am J Physiol 238:H423–H429, 1980.)