Immediately elevated postoperative serum branched-chain amino acids following effective GI decompression and enteral feeding

Postoperative patients are hypercatabolic. They also suffer a degree of gastrointestinal (GI) dysfunction impairing nutritional intake. Safe enteral absorption had been limited to a maximum of 500 kcal provided over the initial 24 h in all previously reported regimens. Several days of negative nitrogen balance and diminution of serum branched-chain amino acids (BCAA) result. Some data suggest an association with suboptimal wound healing, and immune competence. We tested the hypothesis that immediate exploitation of more effectively preserved GI function could prevent this depressed serum concentration within hours of surgery. Our study group consisted of 34 consecutive elective “open” cholecystectomy patients who had terminal esophageal, gastric, and proximal duodenal decompression. Simultaneous distal duodenal feeding of elemental diet began immediately in the Recovery Room at 300 mL/h for 8–16 h, providing 2,400–4,800 kcal and 100–200 g amino acids. We found that each serum BCAA concentration rose above basal by one hour. The differences reached statistical significance (p ≤ 0.05) within 2 h after surgery, when leucine had risen above basal levels by 70%, isoleucine by 63%, and valine by 26%. Elevations in these BCAA serum concentrations persisted for the duration of feeding. GI function can be maintained and successfully utilized in the immediate postoperative period for absorption of 300 kcal/h. Postoperative depression of serum BCAA concentrations are prevented. The serum BCAA rise of these GI protected and immediately fed postoperative patients contrasts with the 48–72 h decline universally reported with conventional protein- and calorie-deficient regimens. The optimum nutritional regimen for achievement of clinically significant enhanced wound healing, sepsis resistance, and muscle sparing, remains to be determined.