Substrate fuel kinetics in enterally fed trauma patients supplemented with ornithine alpha ketoglutarate

Ornithine-alpha-ketoglutarate (OKG) is a promising anticatabolic agent and the mechanisms of its potential use in trauma patients are not clearly understood.

To determine the altered whole-body protein, lipid and glucose substrate kinetics in trauma victims in the early flow-phase of injury when they were fed enterally with or without OKG.

Fourteen adult, multiple trauma patients who were highly catabolic and hypermetabolic were studied. Whole-body protein ((15)N glycine), fat (2 stage glycerol infusion) and glucose ((3H)glucose) kinetics (t/o) and plasma parameters were measured (A) within 48-60 h after injury before starting nutritional support and then (B) after 4 days of enteral feeding. Group A (n=7, control) received a defined enteral formula (Two Cal HN, 1.4 times BEE calories) and Group B (n=7, OKG) received same isonitrogenous diet replacing 2.62gN/d from the enteral diet by OKG-N (20g OKG/d). RESULTS (Mean+/-SEM): Protein turnover is significantly (P<==0.05) increased in OKG treated patients (4.68+/-0. 15 vs 3.90+/-0.23, gP/kg/day) and glycerol turnover is decreased (0. 87+/-0.16 vs 1.46+/-0.16, micro mole/kg/min). Glucose turnover is not changed. Significant (P<== 0.05) increases in circulating plasma levels of hormones (insulin, 44.2+/-8.4 vs 15.7+/-5.0 ulU/ml, growth hormone 1.68+/-0.33 vs 0.92+/-0.16, ng/ml and IGF-1, 106+/-13 vs 75+/-18, ng/ml) and free amino acids (glutamine, 383+/-20 vs 306+/-25, Proline, 203+/-18 vs 146+/-13 and ornithine, 164+/-27 vs 49+/-5 micro mole/l) are found in OKG treated patients, compared to non OKG patients.

Increased hormone secretion due to OKG and the rapid interaction between the metabolites of OKG at the intermediary metabolism level may be responsible for altered substrate fuel kinetics.