ABSTRACT
INTRODUCTION Circulatory shock is characterized by inadequate systemic tissue perfusion due to altered physiology and reduced blood supply. Hypotension is differentiated from shock by the ability to meet the tissue’s metabolic demands by maintaining tissue perfusion. Tissue perfusion, a function of systemic vascular resistance (SVR) and cardiac output, is significantly reduced in instances where SVR is low and cardiac output is elevated (vasodilatory shock) or where SVR is elevated and cardiac output is reduced. When the latter is accompanied by inadequate intravascular volume, hypovolemic shock is present. Depressed cardiac output with elevated SVR in the presence of adequate intravascular volume defines cardiogenic shock (CS) (Table 34.1).
