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, β-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 μmol/l), vitamin E (13.5±6.6 vs. 20.8±9.2 μmol/l), zinc (5.6±1.9 vs. 8.6±2.3 μmol/l) and selenium (35.0±19.6 vs. 42.9±0.9 μg/l) as well as enhanced plasma glutamine levels (429.6±90.6 vs. 530±200.1 μmol/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.