[Prevention of stress reactions by influencing energy metabolism using the extracorporeal circulation as a model (author's transl)].

Following a brief discussion of the principles and pathophysiology of energy metabolism, the effects of high free fatty acid (FFA) levels upon the organism and the possibilities of preventing their accumulation are commented on. Furthermore, the question of whether extracorporeal circulation (ECC) is comparable to a stress situation is analysed. In a review of previous studies the concept is introduced that the prompt exogenous administration of adequate calories can inhibit the endogenous mobilization of energy in a stress situation. An attempt was already been made to demonstrate this point in relation to catecholamine excretion. The calories should primarily consist of easily-utilizable carbohydrates (concentrated glucose with high doses of insulin), a regimen enabling the administration also of fat emulsions as an additional source of calories even at an early stage. Patients with severe brain injuries received this treatment as from the first day of admission. Evidence that glucose metabolism impairment was successfully overcome after severe shock was obtained in 40 patients receiving glucose-insulin solutions. It was deduced from this study to prevent a stress reaction by the administration of an augmented dose of insulin before ECC. The blood levels of glucose, insulin, lipids (FFA, triglycerides, cholesterol) and heparin, as well as some routinely-determined parameters (coagulation, haematocrit, haemolysis, potassium) were studied in 31 adults undergoing open heart surgery for congenital or acquired diseases of the heart. The incidence of cardiac arrhythmias was also recorded. The metabolic influence of glucose-insulin administration on these parameters was studied in one group of the patients who received 250 ml of 33% glucose (82 g) along with 40 units of insulin-MC (24 U insulin/50 g glucose) over an average period of 80 minutes (0.9 g glucose/kg/h) before heparinization for the ECC, whereas the second group of patients served as controls. The following effects of the administration of insulin plus glucose before the period of ECC were demonstrated: Blood glucose levels were elevated throughout the infusion; within the period of ECC, however, these levels were similar to the control group. Insulin levels were distinctly elevated and remained significantly higher until after the ECC as compared with the controls. Hence, the stage of insulin suppression appears to be surpassed by these means.