Is iohexol an acceptable alternative to barium sulphate for videofluoroscopy swallowing studies? An observational mixed-methods study using the theoretical framework of acceptability

PURPOSE: Videofluoroscopic swallowing studies traditionally use barium sulphate and remains the gold standard for evaluating swallowing disorders. Due to a global shortage, this study investigates the acceptability of iohexol as an alternative. METHOD: An observational mixed-method study in a quaternary hospital. Speech-language pathologists rated 294 swallows across 70 videofluoroscopic swallowing studies on a 5-point Likert scale assessing visibility, while blinded to the contrast used (barium or iohexol). Speech-language pathologists experienced with both agents also completed a qualitative online survey on contrast acceptability. Both data types were given equal weight in analysis. RESULT: Fifteen Speech-language pathologists (mean years of experience 6.87, SD = 5.33) completed visibility ratings; 11 completed the acceptability survey. Acceptability was found to be consistency dependent with iohexol preferred for thin fluids; yet acceptability was also influenced by contrast availability, taste, preparation time, and effort, as well as patient aspiration risk. When blinded to the contrast used, speech-language pathologists were more often satisfied with barium (odds ratio 0.51, 95% CI 0.46-0.58); however, for fluids alone, iohexol was rated more satisfactory (odds ratio 1.26, 95% CI 1.07-1.49). CONCLUSION: Barium sulphate remains preferable for visibility and preparation, but iohexol was also acceptable, particularly for fluids and in situations where barium is unavailable.