A condition of profound and generally acute hemodynamic and metabolic disturbance characterized by failure of the circulatory system to maintain adequate perfusion of vital organs - Clinical indicators: o Reduced mean arterial pressure, tachycardia, tachypnea, cool skin and extremities, acutely altered mental status, oliguria, hypotension (usually, but not always, present), narrow differential pressure (difference between systolic and diastolic blood pressure), low cardiac output leading to a delayed capillary refill o End result is tissue hypoxia, often manifested by lactic acidosis - Clinical manifestations of hypovolemic or cardiogenic shock: o Hypotension, hyperventilation, cold, clammy, cyanotic skin, a weak and rapid pulse, oliguria, mental confusion, and combativeness or anxiety - Clinical manifestations of septic shock: o Chills and fever, warm flushed skin, a lower degree of hypotension, and an increase in cardiac output o If unresponsive to therapy, septic shock progresses to the clinical pattern described for hypovolemic and cardiogenic shock.