Time course of the early pituitary-adrenal and metabolic responses to accidental injury

We have made serial measurements of the plasma adrenocorticotrophic hormone (ACTH), cortisol, glucose, lactate, glycerol, nonesterified fatty acid (NEFA), and beta-hydroxybutyrate concentrations in 14 recently injured patients. We took 6 to 9 blood samples at about 20-minute intervals from each patient within the first 3 hours after accidental injury of moderate severity (Injury Severity Score of 9 to 13). Plasma ACTH varied greatly both with time and between patients; in the majority, it fell throughout the sampling period and in the others, the pattern varied. The changes in plasma cortisol were mostly appropriate to those in ACTH. Plasma glucose and glycerol did not change systematically with time. In contrast, plasma lactate fell, and plasma NEFA, beta-hydroxybutyrate, and the NEFA:glycerol ratio rose, throughout the sampling period. Analysis of variance for these data showed that time after injury made a contribution that was highly significant, although smaller than that arising from differences between patients.