Characterizing the Flow of Thickened Barium and Non-barium Liquid Recipes Using the IDDSI Flow Test

The use of thickened liquids for dysphagia management has become wide-spread. Videofluoroscopy is commonly used to determine dysphagia severity and to evaluatethe effectiveness of interventions, including texture modification, but this requires theuse of radio-opaque contrast media. In order for the results of a videofluoroscopy tohave validity with respect to confirming swallowing safety and efficiency on differentliquid consistencies, it is important to understand the flow characteristics of the contrastmedia used and how the flow of these stimuli compares to the flow of liquids that areprovided outside the assessment context. In this study, we explored the flowcharacteristics of 20% w/v barium and non-barium stimuli prepared using starch andgum thickeners to reach the slightly, mildly and moderately thick liquid categoriesdefined by the International Dysphagia Diet Standardisation Initiative (IDDSI). Our goalwas to identify recipes that would produce stimuli with stable flow properties over a 3h time frame post mixing. Thickener concentration was titrated to achieve matchingflow (i.e., IDDSI Flow Test results within a 1 ml range) across the four stimulus types(non-barium starch, non-barium gum, barium starch, barium gum) within each IDDSIlevel. The combination of barium and thickeners resulted in further thickening, particularly with starch-based thickening agents. A probe of the influence ofrefrigeration showed no difference in flow measures between chilled and roomtemperature stimuli over a 3-h time frame. Overall, recipes with stable flow overthree hours were identified for all barium and non-barium liquids tested.