The influence of syringe geometry on the International Dysphagia Diet Standardisation Initiative flow test

Abstract

SummaryRecently published International Dysphagia Diet Standardisation Initiative (IDDSI) framework provides a new global guideline on texture modification and standardisation for dysphagia patients. The IDDSI flow test determines the usage of the 10‐mL syringe with a fixed length from the zero to the 10‐mL line engraved on the barrel. The objective of this work was to investigate the influences of the other syringe geometries on the IDDSI test. Three syringes of different geometries were used for the test. Results from the IDDSI test (i.e. the amount of residue in the syringe after the gravitational flow for 10 s) depended on the syringe geometries. The actual amount of residue in the syringe can be predicted by calculation using the Hagen–Poiseuille equation. Most importantly, results from the simulation of the residue with changing the syringe geometries demonstrated that the nozzle inner diameter is the most important factor on the IDDSI flow test.