IMMEDIATELY ELEVATED POSTOPERATIVE SERUM BRANCHED-CHAIN AMINO-ACIDS FOLLOWING EFFECTIVE GI DECOMPRESSION AND ENTERAL FEEDING

Postoperative patients are hypercatabolic. They also suffer a degree o f 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 da ys of negative nitrogen balance and diminution of serum branched-chain amino acids (BCAA) result. Some data suggest an association with subo ptimal 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 surge ry. Our study group consisted of 34 consecutive elective ''open'' chol ecystectomy patients who had terminal esophageal, gastric, and proxima l duodenal decompression. Simultaneous distal duodenal feeding of elem ental 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 tha t each serum BCAA concentration rose above basal by one hour. The diff erences reached statistical significance (p less than or equal to 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 functi on can be maintained and successfully utilized in the immediate postop erative period for absorption of 300 kcal/h. Postoperative depression of serum BCAA concentrations are prevented. The serum BCAA rise of the se GI protected and immediately fed postoperative patients contrasts w ith 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 r esistance, and muscle sparing, remains to be determined.