Substantial losses of nutrients may occur during tube (gavage) feeding of fortified human milk. Our objective was to compare the losses of key macronutrients and minerals based on method of fortification and gavage feeding method. We used clinically available gavage feeding systems and measured pre- and post-feeding (end-point) nutrient content of calcium (Ca), phosphorus (Phos), protein, and fat. Comparisons were made between continuous, gravity bolus, and 30-minute infusion pump feeding systems, as well as human milk fortified with donor human milk-based and bovine milk-based human milk fortifier using an in vitro model. Feeding method was significantly associated with fat and Ca losses, with increased losses in continuous feeds. Fat losses in continuous feeds were substantial, with 40 ± 3 % of initial fat lost during the feeding process. After correction for feeding method, human milk fortified with donor milk-based fortifier was associated with significantly less loss of Ca (8 ± 4% vs. 28 ± 4%, p< 0.001), Phos (3 ± 4% vs. 24 ± 4%, p < 0.001), and fat (17 ± 2% vs. 25 ± 2%, p = 0.001) than human milk fortified with a bovine milk-based fortifier (Mean ± SEM).
Keywords: calcium; enteral nutrition; lipids; neonates; phosphorous; protein.