Understanding the Viscosity of Liquids used in Infant Dysphagia Management

A Prospective Study of Parental Experience with Thickening Feeds for Children with Oropharyngeal Dysphagia and Gastroesophageal Reflux

Thickening is efficacious and commonly recommended for oropharyngeal dysphagia and gastroesophageal reflux. Little is known about parental experience with this practice. Results of this cross-sectional questionnaire study suggest attitudes are positive, but parents frequently adjust recipes/nipple sizes, which might increase aspiration risk. Clinical follow-up is essential to ensure safe feeding.

Using an Automated Speech Recognition Approach to Differentiate Between Normal and Aspirating Swallowing Sounds Recorded from Digital Cervical Auscultation in Children

Use of machine learning to accurately detect aspirating swallowing sounds in children is an evolving field. Previously reported classifiers for the detection of aspirating swallowing sounds in children have reported sensitivities between 79 and 89%. This study aimed to investigate the accuracy of using an automatic speaker recognition approach to differentiate between normal and aspirating swallowing sounds recorded from digital cervical auscultation in children. We analysed 106 normal swallows from 23 healthy children (median 13 months; 52.1% male) and 18 aspirating swallows from 18 children (median 10.5 months; 61.1% male) who underwent concurrent videofluoroscopic swallow studies with digital cervical auscultation. All swallowing sounds were on thin fluids. A support vector machine classifier with a polynomial kernel was trained on feature vectors that comprised the mean and standard deviation of spectral subband centroids extracted from each swallowing sound in the training set. The trained support vector machine was then used to classify swallowing sounds in the test set. We found high accuracy in the differentiation of aspirating and normal swallowing sounds with 98% overall accuracy. Sensitivity for the detection of aspiration and normal swallowing sounds were 89% and 100%, respectively. There were consistent differences in time, power spectral density and spectral subband centroid features between aspirating and normal swallowing sounds in children. This study provides preliminary research evidence that aspirating and normal swallowing sounds in children can be differentiated accurately using machine learning techniques.

Thickened Formulas Used for Infants with Dysphagia: Influence of Time and Temperature

Infant dysphagia is commonly managed using thickened formulas. Substantial research investigates thickening of a variety of beverages for adults and children, yet few studies address the unique considerations of thickened formula for infants. Understanding the consistency and behaviour of thickened formula will guide clinicians and parents to make informed decisions to minimise risk of aspiration. To investigate the effect of time and storage temperature on the flow properties of thickened formula, four formulas and two thickeners currently utilised at a major metropolitan children's hospital in Australia were tested in combinations, at refrigerated and room temperatures. Their flow properties were measured at three time-points (baseline, 1 h, 24 h) using the International Dysphagia Diet Standardisation Initiative (IDDSI) Flow Test, the current clinical standard for classifying drinks based on flow properties. A combination of paired t tests, Wilcoxon Signed-Rank tests, repeated measures analysis of variance (ANOVA) and Cohen's d was used to statistically compare flow properties and determine the significance of the observed data. At baseline, 98% (n = 48) of the thickened formula bottles were measured as thinner than the "mildly thick" IDDSI category to which they were prepared. Conversely, at 24 h, 17% were measured thicker than "mildly thick" whilst 10% measured too thin for the category "mildly thick". Refrigerated samples increased in thickness more significantly over time compared to those stored at room temperature. Two of the formulas, when thickened, resulted in a foamy mixture non-compatible with IDDSI Flow Test measurement. As a result, these two formulas were not subjected to further testing. All the tested commercial products behaved differently to each other and were unstable over varying times and temperatures. This finding indicates the need for improved guidelines regarding preparation and storage of thickened fluids. Further investigation is recommended into the chemical processes underlying the observed deviations.

Safety and Efficacy of Specially Designed Texture-Modified Foods for Patients with Dysphagia Due to Brain Disorders: A Prospective Study

Providing texture-modified food for patients with dysphagia is a cornerstone of dysphagia treatment. This study aimed to evaluate the safety and efficacy of a specially designed texture-modified food that can be easily swallowed while maintaining the unique taste by adjusting hardness and adhesiveness in patients with brain disorders using a videofluoroscopic swallowing study. We included 101 patients with oropharyngeal dysphagia due to brain disorders who were referred to the rehabilitation department. To evaluate the safety and efficacy of a specially designed texture-modified food, rice gruel was compared with a regular instant rice porridge, and bulgogi mousse was compared with ground bulgogi, which normally serves as a texture-modified diet for patients with dysphagia in our hospital during the videofluoroscopic swallowing study. The Penetration–Aspiration Scale score, oropharyngeal transit time, number of swallows required to maximally eliminate food materials from the oropharyngeal space, and vallecular and pyriform sinus residue after swallowing scale score were compared. Rice gruel required a shorter oropharyngeal transit time and fewer number of swallowing per the given amount of food than regular instant rice porridge; however, no statistical difference was found in the vallecular and pyriform sinus residue after swallowing scale scores and the Penetration–Aspiration Scale scores. Bulgogi mousse required more swallowing and had lower Penetration–Aspiration Scale scores than ground bulgogi; however, no significant difference was found in the oropharyngeal transit time and the vallecular and pyriform sinus residue after swallowing scale scores. The study foods were safe and efficacious compared to control foods usually provided for patients with dysphagia from various brain disorders.

Thickened liquids: do they still have a place in the paediatric dysphagia toolkit?

PURPOSE OF REVIEW

Use of thickened fluids has long been a cornerstone of dysphagia management. However, clinicians and researchers are increasingly questioning their effectiveness and highlighting potential harms. This review aims to present the current state of the evidence for use of thickened fluids in children.

RECENT FINDINGS

The relationship between aspiration and respiratory infection is complex. The role of thickened fluids in improving respiratory health is limited and contradictory. A high level of variability exists in all aspects of thickened fluid use. Little is known about patient and family perspectives on meaningful endpoints for intervention.

SUMMARY

Clinicians should be open and transparent in their decision making with patients and families, acknowledging the limited evidence and the need for individualised care. Further research is needed to establish the efficacy of thickened fluid use in children with regard to improvements in respiratory health, fluid intake and child and family wellbeing.

Oral delivery of peptide therapeutics in infants: Challenges and opportunities

The vast majority of drugs are not designed or developed for pediatric and infant populations. Peptide drugs, which have become increasingly relevant in the past several decades, are no exception. Unfortunately, nearly all of the 60+ approved peptide drugs are formulated for injection, a particularly unfriendly mode of administration for infants. Although three peptide drugs were recently approved for oral formulations, this major advance in peptide drug delivery is available only for adults. In this review, we consider the current challenges and opportunities for the oral formulation of peptide therapeutics, specifically for infant populations. We describe the strategies that enable oral protein delivery and the potential impact of infant physiology on those strategies. We also detail the limited but encouraging progress towards 1) adapting conventional drug development and delivery approaches to infants and 2) designing novel infant-centric formulations. Together, these efforts underscore the feasibility of oral peptide delivery in infants and provide motivation to increase attention paid to this underserved area of drug delivery and formulation.

Fluid-structure interaction modeling of lactating breast: Newtonian vs. non-Newtonian milk

Breastfeeding is a highly dynamic and complex mechanism. The suckling process by the infant involves compression and intra-oral vacuum pressure, leading to milk expression from breast. The accumulated milk from the nipple varies depending on the milk properties and transient flow rate during the suckling cycle. Rheological studies on raw human milk indicate that milk has a non-Newtonian shear-thinning flow behavior. This study aims to investigate the effect of non-Newtonian milk on flow behavior through the breast ductal system using fluid-structure interaction (FSI) simulation. The results of the non-Newtonian effects on flow velocity and the volumetric flow rate of expressed milk are presented. The results show that non-Newtonian Carreau model is promising for the simulation of human milk flow through the breast ductal systems. Also, the results show that the non-Newtonian effects on the milk flow behavior appear for 30-35% of the suckling cycle. Therefore, the Newtonian model is acceptable for the purpose of numerical simulation.

Effect of mixing method on resulting thickness of infant formula

Previous research shows that factors such as time, temperature, nutritional make-up of a liquid, and type of thickening agent can significantly alter the resulting thickness of liquids. This study sought to determine the effect of three distinct mixing methods on the resulting thickness of ready to feed infant formulas mixed to Mildly and Moderately Thick (International Dysphagia Diet Standardization Initiative [IDDSI] Levels 2 and 3) with three different thickening agents. Eight commercially available infant formulas were mixed with three different thickening agents by three different mixing methods. The IDDSI Syringe Flow Test was used to categorize the thickened formulas. Chi square analyses were completed to determine the impact of mixing method on the thickened formulas. The majority (94%) of thickened formula combinations prepared to a target Mildly Thick consistency produced thickened formula that was thinner or thicker than the target. In contrast, the majority (76%) of thickened formula combinations prepared to a target Moderately Thick (IDDSI Level 3) consistency produced thickened formula that was equivalent to the target consistency. A statistically significant relationship was found between mixing methods and resulting IDDSI category for samples mixed to a target of Moderately Thick. The thickening agent and method of mixing must be considered carefully when preparing infant formulas to Mildly and Moderately Thick target IDDSI categories. Based on results of this study, it is recommended that providers utilize a clinical testing method, such as the IDDSI Syringe Flow Test, when attempting to create a Mildly Thick formula consistency.

Frontline Interventions: Considerations for Modifying Fluids and Foods for Management of Feeding and Swallowing Disorders Across the Life Span

Purpose Individuals with dysphagia across the age continuum may require dietary modifications of fluids and foods for safe and adequate oral intake. Considerations of this frontline intervention are presented in this clinical forum dedicated to the discussion of dysphagia. Method This clinical focus article reviews the technical challenges of providing modified fluids and foods across the life span as well as the literature specific to its origins, efficacy, challenges and solutions to standardization, and the methods for ensuring quality service delivery. Conclusion Dietary modification is an often-used method of dysphagia management that presents unique challenges to the clinician for successful application. Speech-language pathologists in clinical practice across all settings must remain dedicated to evidence-based practice as they navigate service delivery of this strategy to individuals with dysphagia across the life span.

An Experimental Study on Human Milk Rheology: Behavior Changes from External Factors

The influence of external factors, including temperature, storage, aging, time, and shear rate, on the general rheological behavior of raw human milk is investigated. Rotational and oscillatory experiments were performed. Human milk showed non-Newtonian, shear-thinning, thixotropic behavior with both yield and flow stresses. Storage and aging increased milk density and decreased viscosity. In general, increases in temperature lowered density and viscosity with periods of inconsistent behavior noted between 6–16 ∘ C and over 40 ∘ C. Non-homogeneous breakdown between the yield and flow stresses was found which, when coupled with thixotropy, helps identify the source of nutrient losses during tube feeding.

Associations between age, respiratory comorbidities, and dysphagia in infants with down syndrome

OBJECTIVES

Children with Down syndrome (DS) have a high risk of dysphagia and the pediatric pulmonologist may be involved in diagnosis and management. The objective of this study is to evaluate the associations between age, dysphagia, and medical comorbidities in young children with DS. We hypothesized that swallow study findings are more likely to change in younger infants and that medical comorbidities may be associated with dysphagia.

STUDY DESIGN

Results of videofluoroscopic swallow studies (VFSS) and fiberoptic endoscopic evaluation of swallowing (FEES) from 2010 to 2016 were collected retrospectively in children with DS with initial swallow study at less than 12 months of age. Results were analyzed for findings and change based on age at initial study, reason for referral, and medical comorbidities.

RESULTS

One hundred eleven infants with 247 VFSS and 14 FEES were included. Deep laryngeal penetration and/or aspiration were found in 31.9% of infants less than 6 months and 51.3% of infants 6 to 12 months. Children with initial swallow study performed at greater than or equal to 6 months of age were more likely (80.0%) to have unchanged findings on follow-up study compared to children imaged at less than 6 months (35.3%). Laryngomalacia, pulmonary hypertension, pneumonia, and congenital cardiac disease were associated with dysphagia.

CONCLUSION

We confirmed that dysphagia is common in infants with DS and comorbidities and provided preliminary evidence that swallow study findings may be more likely to change in children tested under 6 months of age. Providers should consider that results for instrumental swallow studies may change, particularly if the test was completed on a young infant.

Swallowing Analyses of Neonates and Infants in Breastfeeding and Bottle-feeding: Impact on Videofluoroscopy Swallow Studies

Introduction  Dysphagia, when left untreated, can result in an increase in morbidity and mortality rates, especially among infants with history of life-threatening neonatal diseases. The videofluoroscopy swallowing study (VFSS) is considered the gold standard for the diagnosis of dysphagia. There are few imaging studies of infant swallowing based on videofluoroscopy, none of which were performed during breast-feeding. Objective  To analyze the similarities and differences in infant swallowing function -regarding the feeding method - breast or bottle - and the impact on videofluoroscopy findings. Methods  A retrospective study of 25 VFSSs of breastfeeding and bottle-feeding infants was performed. The studied variables were: oral capture and control; tongue versus mandible movement coordination; sucking pattern; mandible excursion; liquid flow; bolus retention; laryngeal penetration; tracheal aspiration; clearing of material collected in the pharynx; and gastroesophageal reflux (GER). Results  The study showed a statistically significant association between nipple/areole capture; oral control; sucking pattern; mandibular excursion; liquid flow and feeding method. The velar sealing deficit, the place that trigger the pharyngeal swallow, food retention in the pharyngeal recesses, laryngeal penetration and GER were also factors associated with the feeding method. Conclusion  The analysis of the swallowing characteristics of both feeding methods revealed significant differences between them, with an impact on the diagnosis in the VFSSs, especially regarding velar function.

Modulation of Tongue Pressure According to Liquid Flow Properties in Healthy Swallowing

Purpose During swallowing, the tongue generates the primary propulsive forces that transport material through the oral cavity toward the pharynx. Previous literature suggests that higher tongue pressure amplitudes are generated for extremely thick liquids compared with thin liquids. The purpose of this study was to collect detailed information about the modulation of tongue pressure amplitude and timing across the range from thin to moderately thick liquids. Method Tongue pressure patterns were measured in 38 healthy adults (aged under 60 years) during swallowing with 4 levels of progressively thicker liquid consistency (International Dysphagia Diet Standardisation Initiative, Levels 0 = thin, 1 = slightly thick, 2 = mildly thick, and 3 = moderately thick). Stimuli with matching gravity flow (measured using the International Dysphagia Diet Standardisation Initiative Flow Test; Cichero et al., 2017 ; Hanson, 2016 ) were prepared both with/without barium (20% weight per volume concentration) and thickened with starch and xanthan gum thickeners. Results After controlling for variations in sip volume, thicker liquids were found to elicit significantly higher amplitudes of peak tongue pressure and a pattern of higher (i.e., steeper) pressure rise and decay slopes (change in pressure per unit time). Explorations across stimuli with similar flow but prepared with different thickeners and with/without barium revealed very few differences in tongue pressure, with the exception of significantly higher pressure amplitudes and rise slopes for nonbarium, starch-thickened slightly and mildly thick liquids. Conclusions There was no evidence that the addition of barium led to systematic differences in tongue pressure parameters across liquids with closely matched gravity flow. Additionally, no significant differences in tongue pressure parameters were found across thickening agents. Supplemental Material https://doi.org/10.23641/asha.7616537.

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 evaluate the effectiveness of interventions, including texture modification, but this requires the use of radio-opaque contrast media. In order for the results of a videofluoroscopy to have validity with respect to confirming swallowing safety and efficiency on different liquid consistencies, it is important to understand the flow characteristics of the contrast media used and how the flow of these stimuli compares to the flow of liquids that are provided outside the assessment context. In this study, we explored the flow characteristics of 20% w/v barium and non-barium stimuli prepared using starch and gum thickeners to reach the slightly, mildly and moderately thick liquid categories defined by the International Dysphagia Diet Standardisation Initiative (IDDSI). Our goal was to identify recipes that would produce stimuli with stable flow properties over a 3 h time frame post mixing. Thickener concentration was titrated to achieve matching flow (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 IDDSI level. The combination of barium and thickeners resulted in further thickening, particularly with starch-based thickening agents. A probe of the influence of refrigeration showed no difference in flow measures between chilled and room temperature stimuli over a 3-h time frame. Overall, recipes with stable flow over three hours were identified for all barium and non-barium liquids tested.