[Effects of surgery on plasma amino acids levels]

This study was aimed at comparing pre- and immediately postoperative plasma amino acids levels in ten patients undergoing moderately important surgery and anaesthetised using the same protocol. Amino acid levels were measured using and automatic analyser equipped with an ion exchanger column. Changes in total blood amino acid levels showed wide variations. It is difficult to assess the role played by possible changes in blood volume, and for this reason results are expressed as a percentage of total amino acid levels. Under such conditions, findings were as follows: - taurine and alamine rose significantly; - there was a significant fall in serine, citrulline, alpha- amino-butyric acid and isoleucine. The results of this study differed markedly from findings reported in the literature: the authors noted a fall in plasma amino acid levels both in relation to preoperative levels as well as in relation to "normal" levels in the literature. This could be related to haemodilution, this hypothesis being supported by the fall in total aminogram in eight of the ten patients of the group. The most notable fact in the variations seen in this study was the rise in plasma alamine levels which could be indicative of a fall in gluconeogenesis. This hypothesis requires confirmation.