Metabolism of prolonged shock

Dogs in shock due to controlled cardiac tamponade for 4 or 12 h were studied to determine which of the metabolic changes characteristic of early shock persisted if the shock state was prolonged. Moderate hyperglycemia and severe lactacidemia were present in the first few hours but the levels returned to near normal values by the end of 12 h. The entry rate of lactic acid into the circulation as well as the rate of glycogenolysis was high in the first 4 h but decreased thereafter even though skeletal muscle glycogen stores were not exhausted. In early but not in late shock glycogen accumulated in the heart. Glucose entry and exit rates were significantly elevated in early shock only. Increased protein utilization and decreased fatty acid mobilization persisted throughout the experimental period. Both in early and late shock the incorporation of labeled free fatty acid into tissue lipids was decreased in most organs. In the diaphragm free fatty acid incorporation only decreased in late shock. In the heart and lung, incorporation was higher than normal in the early stages but was at control levels after 12 h of shock.