Myocardial substrate utilization in anaphylactic shock.

Changes in myocardial substrate utilization were studied in anesthetized dogs following the production of anaphylactic shock. Mean arterial blood pressure, cardiac output, and pH decreased significantly during this form of shock. Myocardial FFA oxidation was greatly diminished especially within the first hour following challenge and lactate uptake more than doubled during the same time. Thus, it is concluded that myocardial substrate utilization shifted away from FFA and towards lactate during anaphylactic shock and these changes resembled those observed following an acute, severe hemorrhage, or the administration of E. coli endotoxin.