In vitro radionuclide labeling characteristics of blenderized tube feeds for quantitative gastric motility assessment

Gastric emptying scintigraphy (GES) using technetium-99m-sulfur colloid (^99mTc-SC) is an important tool for evaluating feeding intolerance. Stable ^99mTc-SC binding to the solid component of the meal is imperative for accurate result interpretation. The objective of this study is to quantify the binding characteristics of ^99mTc-SC to blenderized tube feeds. ^99mTc-SC stably bound to chicken and egg blenderized diets over 4 h, the typical duration of gastric emptying exams. While more ^99mTc-SC was found in the liquid phase for both blenderized feeds compared to the standard egg meal, this was within clinically acceptable range (chicken-blend T₀ 15%, T_1h 17%, and T_4h 18.5%; egg-blend T₀ 12%, T_1h 11%, and T_4h 10%; egg-standard T₀ 2.5%, T_1h 3.5%, and T_4h 7%, p < 0.05 for all pairwise comparisons at each time point except chicken-blend vs. egg-blend at T₀). Results suggest that ^99mTc-SC binding characteristics in blenderized feeds are acceptable for use in GES.