Metabolic control in non-septic patients with musculoskeletal injuries

Changes in gaseous exchange, plasma substrates and hormones and excretion of nitrogen were followed in 13 non-septic male patients, all of whom had sustained at least 1 fracture of a long bone. Results were compared with normal subjects given glucose to produce a range of substrate and hormone concentrations. Over the 3 weeks following injury, oxidation of fat decreased from high levels whilst oxidation of carbohydrate rose. This reflected to some extent changes in availability of substrate, but early after injury oxidation of fat was higher than expected for the concentration of free fatty acids in plasma and later oxidation of carbohydrate was increased relative to concentrations of glucose and insulin. Concentrations of insulin in plasma were high for the prevailing concentrations of glucose, and peak urinary excretion of nitrogen coincided with maximum levels of insulin. It was concluded that in the injured patient there are changes at the level of utilization and oxidation of plasma substrates as well as in their availability, and that there is marked unresponsiveness of protein metabolism to the normal anabolic effect of insulin.