The Novel Role of Amino Acid Parenteral Nutrition in the Perioperative Management of Upper Gastrointestinal Surgery.

［Background］Loss of muscle mass after gastrectomy in gastric cancer patients negatively affects the continuation of adjuvant chemotherapy and is related to the poor prognosis. On the other hand, administration of branched-chain amino acids（BCAA）and exercise treatment prevent muscle loss in elderly patients with primary sarcopenia. We evaluated the effect of combined parenteral nutrition（PPN）and exercise treatment to prevent loss of muscle mass after surgery for gastric cancer（UMIN000042579）.［Methods］In the study group, an infusion solution containing amino acids, glucose and fat emulsions was selected as PPN in the early postoperative period. Parenteral nutrition was continued until postoperative day 5. In the control group, a maintenance infusion was selected, and fat emulsion was not used in combination. Exercise intervention based on walking was started on the first day after surgery for both patients in the test group and control group. For exercise after discharge, a target number of steps is set for each age group, and light exercise such as squats is added according to the target number of steps. The primary endpoint was the rate of lean body mass reduction on the 7th day after surgery. The secondary endpoints were the rates of lean body mass reduction up to 1 month and 3 months after surgery［. Results］The reduction rate of lean mass on the 7th day after surgery was - 0.2％ in the study group and -1.7％ in the control group（P=0.21）. One month after surgery, the percentage of lean body mass decreased was +0.3％ in the study group and -4.5％ in the control group（P=0.038）. There was no significant difference between the two groups in the percentage of lean body mass reduction 3 months after surgery（the study group：-3.3％, the control group：-3.5％, P=0.47）［. Conclusions］Intravenous administration containing amino acids, glucose and fat emulsion combined with early exercise treatment after gastrectomy suppressed the loss of lean body mass 1 month after surgery.