Net protein anabolism with hypocaloric parenteral nutrition in obese stressed patients

Thirteen obese patients requiring parenteral nutrition for postoperative complications were studied prospectively to evaluate the efficacy of hypocaloric, high-protein parenteral feeding. Nonprotein caloric intake averaged 881 kcal/d or 51.5% of the patients' measured resting energy expenditure. Protein intake averaged 2.13 +/- 0.59 g/kg IBW. Serum albumin and TIBC increased significantly (2.8 +/- 0.5 g/dL to 3.2 +/- 0.4 g/dL, p less than 0.01, and 196 +/- 39 micrograms/dL to 248 +/- 49 micrograms/dL, p less than 0.05, respectively), and subjects lost weight (120.0 +/- 60.0 kg to 109.7 +/- 32.5 kg, p less than 0.05). Nitrogen balance studies in eight subjects suggested nitrogen equilibrium or positive balance can be achieved (+2.4 +/- 1.9 g/d). All patients exhibited complete tissue healing of wounds and abscess cavities and closure of fistulae. In obese, protein-depleted surgical patients net protein anabolism and clinical efficacy can be achieved with hypocaloric, high-protein feeding. Abundant endogenous fat stores provide obligatory energy.