Relations Between Circulatory and Metabolic Changes in Sepsis

The classic approach to human sepsis focuses on the role of various patho­ logic bacteria and fungi as infectious agents of varying potency. This review emphasizes that sepsis is an acquired disease of intermediary metabolism induced by infectious agents and producing characteristic patterns of meta­ bolic and physiologic host responses. These fundamental abnormalities in the biochemical processes and hor­ monal regulations of substrate utilization and oxidative energy generation interfere with the normal flux of energetic fuels and metabolic catabolic byproducts between muscle, liver, and adipose tissue. These fuel-energy deficits result in incomplete catabolism of aromatic amino acids and may generate as yet incompletely identified vasoactive substances that induce the pathophysiologic peripheral vascular pressure:flow relations characteristic of the septic process. In the septic host who retains the capability for a heightened sympathetic response, the resultant cardiac inotropic compensa­ tion to these vascular tone abnormalities appears to be a major factor in the development of the septic hyperdynamic state and its consequent pulmo­ nary perfusion maldistribution abnormality. All of these factors interact with the septic-induced alterations in capillary permeability and with the energetically induced protein-calorie malnutrition to produce a septic auto­ cannibalism which alters the balance