Resistance of nitrogen metabolism to growth hormone treatment in the early phase after injury of patients with multiple injuries.

OBJECTIVES AND DESIGN

Several studies have shown an anticatabolic effect of recombinant human growth hormone (rhGH) in surgical patients. We investigated, in a prospective, randomized, double blind, and placebo-controlled study, the effect of r-hGH on hormone and nitrogen metabolism in 14 patients with multiple injuries in the early phase of injury.

MATERIALS AND METHODS

All patients were treated in the intensive care unit, had mechanical ventilation, and were highly catabolic, with a mean daily nitrogen loss of 13.2 +/- 1.8 g. r-hGH was given subcutaneously (once a day, at 8 PM) in a dosage of 0.2 IU/kg.d for seven days, starting on the second day after injury.

RESULTS

Administration of r-hGH evoked a significant increase in plasma concentrations of GH, insulin-like growth factor-I (IGF-I), and insulin-like growth factor binding-protein-3 (IGFBP-3). No significant differences were found for either daily or cumulative nitrogen balances (-103.1 +/- 14 g for patients receiving r-hGH and -92.1 +/- 18.1 for those with placebo). r-hGH therapy did not affect skeletal muscle extracellular water, nor did it affect plasma or muscle concentrations of total free amino acids or glutamine. Plasma albumin, prealbumin, and retinol-binding protein concentrations were also unchanged by r-hGH therapy, as were the urinary excretion of potassium and urea.

CONCLUSIONS

We conclude that elevated plasma levels of GH, insulin, and IGF-I are unable to effect a protein anabolic drive in patients with multiple injuries during the early postinjury phase and assume that this r-hGH resistance to nitrogen metabolism takes place at the level distal to IGF-I.