Sequential changes in insulin-like growth factor 1, plasma proteins, and total body protein in severe sepsis and multiple injury

Background: Our group wanted to test the hypothesis that plasma levels of insulin-like growth factor 1 (IGF-1), transferrin, and prealbumin are useful markers of nutritional progress in severe sepsis and multiple injury Methods: Measurements of IGF-1 and plasma proteins were made in critically ill patients as soon as they were hemodynamically stable and 5, 10, 15, and 21 days later. The magnitude and direction of the measured changes were compared with the magnitude and direction of the change in total body protein in the same time period. Results: Fourteen patients with severe sepsis and 10 multiply injured patients were studied. As a group they had an increased metabolic expenditure that peaked at 153% of normal and lost similar to 12.0% of total body protein. An early fall in IGF-1 and plasma proteins accompanied a marked acute phase response, and recovery occurred while hypermetabolism and net proteolysis continued. No correlation existed between changes in IGF-1 or plasma proteins and the change in total body protein. Conclusions: Plasma levels of IGF-1, transferrin, and prealbumin are not useful for following changes in protein stores early in the course of critical illness.