Glutamine and ornithine-α-ketoglutarate but not branched-chain amino acids reduce the loss of muscle glutamine after surgical trauma

The concentration of free glutamine in skeletal muscle decreases characteristically after surgical trauma. In animal studies a correlation between muscle protein synthesis and the glutamine concentration is reported. For pharmaceutical reasons, commercially available amino acid solutions do not contain glutamine. Therefore, at present, postoperative total parenteral nutrition does not provide glutamine. Several modifications of the composition of the amino acid solutions given in total parenteral nutrition have been evaluated recently. Ornithine-α-ketoglutarate preserves muscle protein synthesis and spares nitrogen after elective surgery, and an extra supply of branched-chain amino acids improves muscle protein synthesis in animals. Patients undergoing elective abdominal surgery (n = 33) received isocaloric (135 kJ/kg body weight/24 h) and isonitrogenous (0.2 g N/kg body weight/24 h) total parenteral nutrition for three days immediately following surgery. Administration of glutamine and ornithine-α-ketoglutarate as part of the amino acid supply reduced the loss of muscle glutamine from 40% to 25% (P \u3c .05). Additional supplementation of branched-chain amino acids produced no such effect, however, as compared with the control group. Further clinical trials including glutamine and ornithine-α-ketoglutarate are advocated. © 1989