Shock is a pathological state resulting from inadequate delivery, increased demand or poor utilization of metabolic substrates (i.e., oxygen and glucose), which leads to cellular dysfunction and cell death. This then leads to progressive acidosis, endothelial dysfunction and inflammatory cascade that results in end-organ injury. Early in the course of shock, compensatory mechanisms may attempt to augment cardiac output (CO) and/or systemic vascular resistance (SVR) in an effort to improve tissue perfusion. Without treatment, those compensatory mechanisms are overwhelmed, leading to decompensated shock, multiorgan failure (MOF) and death.