Implications of the National Dysphagia Diet: A Literature Review

1. Implications of the National Dysphagia Diet: A Literature Review Noel McAuliffe Wayne State University Dr. Fleming March 2013

2. Overview • Explore the existing literature concerning the implications of the National Dysphagia Diet • Research in the literature suggests several variables that complicate the standardization of the National Dysphagia Diet • Variables: temperature, time, thickening agents used, and clinician interpretations

3. Introduction • The goal of dysphagia treatment: ensure safe and adequate nutrition and hydration for the patient • Diet modifications • American Dietetic Association established a set of standards and terminology to regulate the application of diet modifications used to manage dysphagia • This set of standards and terminology is known as the National Dysphagia Diet

4. Liquid Thickening Products • Inconsistencies in the rheological properties of both instant food thickeners and commercially packaged pre-thickened beverages • Temperature influence both of these products • Commercially packaged pre-thickened beverages were less viscous than the guidelines set by the National Dysphagia Diet Task Force • Instant food thickener was more likely to be within the guidelines than the commercially packaged pre-thickened beverages • Adeleye & Rachal, 2007

5. Liquid Thickening Products • Variation among the starch-based thickening agents • All of the viscosity limits were within the guidelines set by the National Dysphagia Diet Task Force • However, there was variation of the consistency and structure of the liquids that used the starch-based thickening agents • Payne, Methven, Fairfield, & Bell, 2011

6. Clinician Interpretation • Subjective Measurements • Interpretation of product directions • Correctly identify the viscosity of a physical sample of the liquid • The study found that physical manipulation of the liquids was a more accurate subjective measurement • Steele and Goff, 2003

7. Temperature and Time • gum-based food thickeners were more likely , than starch-based food thickeners to maintain a consistent level of viscosity over time • As the amount of time that the liquid is allowed to thicken increases, the viscosity of the liquid also increases • As temperature increased, the viscosity decreased • Garcia, Chambers, Matta, & Clark, 2008

8. Time • Increase in viscosity measurements over time with nectar-thick and honey-thick liquids • Garcia, Chambers, Matta, and Clark, 2005 • Increased viscosity for starch-thickeners when the thickening agent was allowed to thicken for thirty minutes • Dewar and Joyce, 2006

9. Conclusion • Inconsistencies regarding the application of the National Dysphagia Diet • Clinical Application • Patient drink preferences • Patient’s rate of beverage consumption • Type of thickening products the facility has available

10. References • Adeleye, B., & Rachal, C. (2007). Comparison of the rheological properties of ready-to-serve powdered instant food thickeners at different temperatures for dysphagic patients. Journal of the american dietetic association, 10, 1176-1182. • Dewar, R., & Joyce, M. (2006). Time-dependent rheology of starch thickener and the clinical implications for dysphagia therapy. Dysphagia, 10, 264-269.

11. References • Garcia, J., Chambers, E., Matta, Z., & Clark, M. (2005). Viscosity measurements of nectar- and honey-thick liquids: Product liquid and time comparisons. Dysphagia, 20, 325-335. • Garcia, J., Chambers, E., Matta, Z., & Clark, M. (2008). Serving temperature viscosity measurements of nectar- and honey-thick liquids. Dysphagia, 23, 65-75.

12. References • Payne, C., Methven, L., Fairfield, C., & Bell, A. (2011). Consistently inconsistent: Commercially available starch-based dysphagia products. Dysphagia, 26, 27-33. • Steele, C., & Goff, H. (2003). The rheology of liquids: A comparison of clinicians’ subjective impressions and objective measurement. Dysphagia, 18, 182-195.