Oxygen transport

The primary role of the cardiorespiratory system is to meet the metabolic demands of the body by delivering adequate amounts of oxygen (O2). The quantity of oxygen extracted by the body’s tissues can be increased significantly under physiologic conditions to satisfy cellular needs. This provides an important buffer that allows the maintenance of adequate oxygen consumption during times of increased demand. Despite this reserve, multiple pathophysiologic insults can disrupt this balance and result in shock states, including hypovolemia, cardiac failure, neurologic injury, anaphylaxis, and sepsis.