The Measurement of Thickened Liquids Used for the Management of Dysphagia

Abstract

Abstract. Dysphagia is a condition where a person has difficulty in swallowing. This can lead to reduced dietary intake, dehydration and malnutrition and also aspiration of material into the lungs and asphyxiation. Using thickened fluids slow the act of swallowing and by doing so enhance safe swallowing. A common method of thickening drinks is to use a powdered thickener, but this can lead to problems in ensuring that the consistency of the degree of thickening appropriate to an individual is maintained by those making up the fluids. There is also no assurance that the thickness of thickened liquids is consistent across commercial manufacturers. In this field viscosity is typically measured using a Line Spread Test, with the resulting viscosities being described by such terms as nectar-honey-or pudding-thick. This test is prone to many variations in operating conditions and so cannot provide accurate reproducible data. In this paper we have used conventional rheology (dynamic oscillatory using a couette cell) to provide quantitative measurement of the development in thickness of various beverages as a fianction of time. It was found fruit juices typically required less thickener and milk more to achieve the same thickness, but that the degree of thickening varied non-linearly with addition level.

Understanding the Rheological Parameters of Thickened Fluids for Dysphagia Sufferers

“…Several manufacturers have stopped the production of starch based thickener due to many limitations that have been found. It was found that starch based thickeners have a long standing time; that is, it keeps thickening even after ten minutes of standing after mixing (Nicholson et al, 2008). Nevertheless, several manufacturers use a mixture of modified maize starch, guar gum and xanthan gum as their main ingredients.…”

“…This is because there are many factors that affect the ability to reliably produce thickened liquids with a consistent thickness level (Pelletier, 1997, Mills, 2008. These factors include a lack of knowledge about preparing thickened fluids, (Rosenvinge and Starke, 2005), differences in the behaviour of thickening agents , Sopade et al, 2008a, Sopade et al, 2008b, Garcia et al, 2005, solids content of the liquid (Sopade et al, 2008a) and differences in dispersing media , Garcia et al, 2005, Nicholson et al, 2008) amongst other parameters.…”

“…powdered thickener) to their drinks to make thickened fluids. Apart from offering greater diversity in flavours, using a powder instead of pre-thickened drinks is more cost-effective (Nicholson et al, 2008). McCormick et al (2009) reported that the fluids consumed in pre-thickened form were found to be more healthy in comparison with drinks thickened with powdered thickener.…”

“…However, patients who live at home often prefer to add a powdered thickener to their drinks to make thickened fluids. This is mainly because using a thickening agent offers greater diversity in flavour and may be less expensive compared to pre-thickened drinks (Nicholson et al, 2008). However, patients and carers have difficulty preparing thickened drinks to the correct thickness level.…”

“…This is because there are many factors that affect the ability to reliably produce thickened liquids with a consistent level of thickness. These factors are: differences in thickening agent , Sopade et al, 2008b, Garcia et al, 2005 solids content of the liquid (Sopade et al, 2008a), serving temperature (Garcia et al, 2008), and differences in dispersing media , Garcia et al, 2005, Nicholson et al, 2008.…”