POSTTRAUMATIC HORMONAL ENVIRONMENT DURING TOTAL PARENTERAL-NUTRITION

Hormonal responses to major trauma trigger a cascade of metabolic adju stments leading to catabolism and substrate mobilization. Energy defic it and energy surfeit have profound effects on hormone levels. To char acterize the course of changes in regulatory hormone levels after mult iple injury, we measured the plasma levels of eight hormones, once wit hin 48-60 h after injury in the fasting state and then daily for 5 day s during the administration of total parenteral nutrition in 10 hyperm etabolic, highly catabolic, and severely injured adult patients. Acute deficiency in anabolic insulinlike growth factor 1 (IGF-1) and growth hormone levels and elevated levels of counterregulatory stress hormon es and insulin were seen as a result of trauma. Provision of nutrition on the 1st day has no effect on IGF-1 and cortisol levels. However, g rowth hormone levels are raised to normal, and the nitrogen balance is improved. Over the next 4 days, there were no appreciable changes in these parameters. The persistent low levels of IGF-1 reflect the alter ed nutrition status of the patients, as characterized by the continued negative nitrogen balance and elevated cortisol levels in the early p osttrauma period. Anabolic IGF-1 and insulin levels showed significant negative correlation with the catabolic indicators 3-methylhistidine and catecholamine excretion. The results suggest that IGF-1 is regulat ed by nutritional intake independently of growth hormone and may be a better nutrition indicator.