Early enteral gut feeding with conditionally indispensable pharmaconutrients is metabolically safe and is well tolerated in postoperative cancer patients--a pilot study

BACKGROUND & AIMS: Postoperative early enteral gut feeding with conditionally indispensable pharmaconutrients can contribute to minimize trauma-induced gut damage. Aim of this pilot study was the evaluation of metabolic effects and gastrointestinal tolerance of a new enteral supplement. METHODS: In a prospective open clinical trial, 20 cancer patients received the test supplement containing glutamine (as dipeptides), antioxidative (pro-)vitamins (C, E, beta-carotene), maltodextrine, tributyrine, sodium, zinc, and selenium within 2-3 h after elective gastrointestinal surgery continuously via jejunostomy tube for 3 postoperative days (500 ml/day). From postoperative day 3-5, additional enteral nutrition (1500 kcal/6270 kJ/day) was given. Metabolic effects (substrate monitoring, hematology, liver/kidney parameters) and tolerance (nausea, vomiting, flatulence, constipation, diarrhea) was assessed through the study. RESULTS: Gastrointestinal tolerance of the supplement was excellent: no adverse events related to the product were documented. Significantly increased mean plasma levels (day 3 vs. day 1) of vitamin C (13.0 +/- 7.3 vs. 62.8 +/- 29.7 micromol/l), vitamin E (13.5 +/- 6.6 vs. 20.8 +/- 9.2 micromol/l), zinc (5.6 +/- 1.9 vs. 8.6 +/- 2.3 micromol/l) and selenium (35.0 +/- 19.6 vs. 42.9 +/- 0.9 microg/l) as well as enhanced plasma glutamine levels (429.6 +/- 90.6 vs. 530 +/- 200.1 micromol/l) reflected an effective absorption of substrates supplied. Adverse effects on organ functions and hematology were not observed. CONCLUSIONS: Early postoperative gut feeding with the newly developed enteral supplement shows no adverse effects, is well tolerated in cancer patients and provides a novel method to deliver conditionally indispensable pharmaconutrients.