Effect of hemodialysis on plasma amino acid concentrations in healthy dogs

Objective - To characterize the effect of maintenance hemodialysis on plasm a amino acid concentrations and to quantitate free amino acid losses into t he dialysate during hemodialysis in healthy dogs. Animals - 8 healthy adult dogs. Procedure - Five dogs received hemodialysis treatments 3 times per week for 4 weeks. Plasma amino acid concentrations were evaluated once per week for 4 weeks in each of the 5 dogs prior to hemodialysis (time 0), 90 minutes d uring hemodialysis, and immediately after hemodialysis (180 minutes). Total free amino acid concentrations and plasma amino acid concentrations (time 0, 90 minutes, and 180 minutes) in the dialysate were evaluated in 3 dogs t hat received 1 hemodialysis treatment. Results - Significant time versus week interactions with any plasma amino a cid were not detected; however, significant decreases in all plasma amino a cid concentrations measured were detected at the midpoint of dialysis (46 /- 2%) and at the end of each dialysis session (38 +/- 2%). Mean (+/- SEM) total free amino acid loss into the dialysate was 2.7 +/- 0.2 g or 0.12 g/k g of body weight. Conclusions and Clinical Relevance-Hemodialysis is associated with signific ant alterations in plasma amino acid concentrations and loss of free amino acids into the dialysate. Loss of amino acids into the dialysate, coupled w ith protein calorie malnutrition in uremic patients, may contribute to depl etion of amino acid stores.