AJP - Endocrinology and Metabolism, Vol 263, Issue 1 E129-E135, Copyright © 1992 by American Physiological Society
Thermogenic and hormonal responses to amino acid infusion in septic humans
J. Arnold, D. Leinhardt, G. Carlson, P. Gray, R. A. Little and M. H. Irving
North Western Injury Research Centre, University of Manchester, United Kingdom.
Metabolic effects of a commercially available amino acid infusate were
investigated in five preoperative patients with abdominal sepsis and five
healthy subjects. Oxygen consumption (VO2) was measured continuously during
the 3-h study, and blood samples were taken regularly for hormone and
metabolite analyses. During 1 h of preinfusion measurements, VO2 was 15%
higher (P less than 0.05) in the septic patients. Preinfusion plasma
cortisol, glucagon, and catecholamines were also significantly elevated in
the septic group. The amino acid solution (9 g nitrogen; 950 kJ; 227 kcal)
was infused into each subject through their central venous catheter during
the 2nd and 3rd h of the study. VO2 increased similarly in both groups by
approximately 21% during the infusion (P less than 0.05), whereas
respiratory quotient increased significantly in only the controls (P less
than 0.05). Plasma insulin and glucagon concentrations rose significantly
in both groups during the infusion, despite little change in glucose
levels. Plasma norepinephrine increased in both groups, although the
response was significant in only the control subjects. In summary, the
amino acid infusate stimulated metabolic rate similarly in the septic and
nonseptic subjects.
