Liquid barium is not representative of infant formula: characterisation of rheological and material properties

The viscosity-enhancing effect of carob bean gum and sodium carboxymethylcellulose when added to infant formula

Despite limited supporting evidence, the practice of thickening breast milk or infant formula with commercially available thickening agents is prevalent. This study explored the viscosity-enhancing impact of carob bean gum (CBG) and sodium carboxymethylcellulose (NaCMC) when added to infant formula at various concentrations and for different thickening durations. The findings indicate that thickening leads to an exponential increase in milk viscosity, from 25% of the recommended dosage onward. This suggests that minor adjustments in dosage can significantly impact formula thickness, underscoring the importance of accurately dosing and preparing infant milk. The considerable variability in viscosity also emphasizes the need for thoughtful selection of teat size, considering the energy expenditure of the sucking infant. When using 50% of the recommended CBG dose or 25% of NaCMC, the resulting viscosity matches that of a commercially available casein-based formula containing CBG for anti-regurgitation. In the case of CBG, a viscosity plateau is only reached after 30 min. Therefore, educating parents on the correct handling and preparation steps for CBG-thickened infant milk is crucial, including a 30-min waiting period to achieve the intended thickening effect.

Effects of barium sulfate on rheological properties and IDDSI flow consistency of liquid stimuli prepared using commercial thickening powders

During videofluoroscopic swallowing study (VFSS), barium sulfate (BaSO4 ) is commonly added into food samples as a radiopaque contrast media for bolus visualization and examination. Accordingly, the consistency and flow behavior of barium stimuli can differ significantly from their non-barium counterparts. Such differences may have a subsequent impact on the validity of VFSS. Therefore, in this study, effects of barium sulfate on the shear and extensional rheological properties and IDDSI (International Dysphagia Diet Standardization Initiative) flow consistency of liquids prepared using various commercial thickening powders were investigated. Results showed that all barium stimuli exhibited shear thinning behavior but with significantly higher shear viscosity compared to the non-barium counterparts. A shift factor of viscosity at shear rate 50 s-1 with values in range of 1.21-1.73 could be used to describe the increase in the viscosity for samples thickened with gum-based thickeners. However, the change in the viscosity was not invariant for the stimuli prepared starch-based thickener. The addition of BaSO4 had a negative impact on extensional properties of samples by demonstrating a faster filament rupture. The extent of impact on the decrease in filament breakup time was more pronounced in xanthan > guar gum ≈ tara gum-based thickeners. Based on the IDDSI flow test, no significant effect of BaSO4 was found on the gum-based thickeners, whereas there was a marked effect in the starch-based sample. These results can be used beneficially to assist clinicians in the dysphagia diagnosis for matching rheological properties of the barium stimuli to enhance effectiveness dysphagia interventions.

Fiberoptic Endoscopic Evaluation of Swallowing in the Breastfeeding Infant

OBJECTIVE

To demonstrate the importance of utilizing fiberoptic endoscopic evaluation of swallowing (FEES) when evaluating breastfeeding infants with suspected dysphagia. Failure to recognize and account for the fundamentally different physiology of the primarily breastfed infant can lead to false assumptions about the safety of breastfeeding in this understudied patient population.

METHODS

Case-series. The medical records of patients referred to an urban, university-based, pediatric hospital for FEES from February 2017 to October 2020 were reviewed. Their presenting symptoms, dysphagia severity, comorbidity, dysphagia workup, and management were analyzed. The standardized Dysphagia Outcome and Severity Scale was used to appraise dysphagia severity.

RESULTS

204 FEES exams were reviewed. 35 were conducted on breastfed infants. 34 of the 35 infants calmed for the FEES exam while breastfeeding. Cohorts were defined by a particular presenting sign (cough, laryngeal congestion, choking, and respiratory illness) and anatomical characteristic (laryngomalacia, vocal cord paralysis, aspiration, penetration, etc.) and then compared to all other exams. The average dysphagia score for all the exams was 2.37. Patients presenting with laryngeal congestion had an average dysphagia score of 2.81. There was no difference in dysphagia score based on comorbidities or anatomy.

CONCLUSIONS

FEES is the instrumental exam of choice when evaluating a primarily breastfed infant who has suspected dysphagia. The exam is well tolerated and provides accurate, objective information while accounting for this population's unique swallowing physiology. Primarily breastfed infants presenting with laryngeal congestion are more likely to have clinically worse dysphagia than those presenting with other clinical symptoms.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:2803-2807, 2023.

Rheological Issues on Oropharyngeal Dysphagia

There is an increasing proof of the relevance of rheology on the design of fluids for the diagnosis and management of dysphagia. In this sense, different authors have reported clinical evidence that support the conclusion that an increase in bolus viscosity reduces the risks of airway penetration during swallowing. However, this clinical evidence has not been associated yet to the definition of objective viscosity levels that may help to predict a safe swallowing process. In addition, more recent reports highlight the potential contribution of bolus extensional viscosity, as elongational flows also develops during the swallowing process. Based on this background, the aim of this review paper is to introduce the lecturer (experts in Dysphagia) into the relevance of Rheology for the diagnosis and management of oropharyngeal dysphagia (OD). In this sense, this paper starts with the definition of some basic concepts on Rheology, complemented by a more extended vision on the concepts of shear viscosity and elongational viscosity. This is followed by a short overview of shear and elongational rheometrical techniques relevant for the characterization of dysphagia-oriented fluids, and, finally, an in-depth analysis of the current knowledge concerning the role of shear and elongational viscosities in the diagnosis and management of OD (shear and elongational behaviors of different categories of dysphagia-oriented products and contrast fluids for dysphagia assessment, as well as the relevance of saliva influence on bolus rheological behavior during the swallowing process).

LUNCH-Lung Ultrasound for early detection of silent and apparent aspiratioN in infants and young CHildren with cerebral palsy and other developmental disabilities: study protocol of a randomized controlled trial

Background

Children with neurological impairment may have dysphagia and/or gastro-esophageal reflux disease (GERD), which predispose to complications affecting the airways, increasing risk for aspiration-induced acute and chronic lung disease, or secondarily malnutrition, further neurodevelopmental disturbances, stressful interactions with their caregivers and chronic pain. Only multidisciplinary clinical feeding evaluation and empirical trials are applied to provide support to the management of feeding difficulties related to dysphagia or GERD, but no standardized feeding or behavioral measure exists at any age to assess aspiration risk and support the indication to perform a videofluoroscopic swallowing study (VFSS) or a fibre-optic endoscopic examination of swallowing (FEES), in particular in newborns and infants with neurological impairments. Lung ultrasound (LUS) has been proposed as a non-invasive, radiation-free tool for the diagnosis of pulmonary conditions in infants, with high sensitivity and specificity.

Methods

A RCT will be conducted in infants aged between 0 and 6 years having, or being at risk for, cerebral palsy, or other neurodevelopmental disease that determines abnormal muscular tone or motor developmental delay assessed by a quantitative scale for infants or if there is the suspicion of GERD or dysphagia based on clinical symptoms. Infants will be allocated in one of 2 groups: 1) LUS-monitored management (LUS-m); 2) Standard care management (SC-m) and after baseline assessment (T0), both groups will undergo an experimental 6-months follow-up. In the first 3 months, infants will be evaluated a minimum of 1 time per month, in-hospital, for a total of 3 LUS-monitored meal evaluations. Primary and secondary endpoint measures will be collected at 3 and 6 months.

Discussion

This paper describes the study protocol consisting of a RCT with two main objectives: (1) to evaluate the benefits of the use of LUS for monitoring silent and apparent aspiration in the management of dysphagia and its impact on pulmonary illness and growth and (2) to investigate the impact of the LUS management on blood sample and bone metabolism, pain and interaction with caregivers.

Trial registration

Trial registration date 02/05/2020; ClinicalTrials.gov Identifier: NCT04253951.

Instrumental and sensory techniques to characterize the texture of foods suitable for dysphagic people: A systematic review

The interest to characterize texture-modified foods (TMFs) intended for people with oropharyngeal dysphagia (OD) has grown significantly since 2011. Several instrumental and sensory techniques have been applied in the analysis of these foods. The objective of the present systematic review was to identify the most appropriate techniques, especially for the food industry and clinical setting. The search was carried out in three online databases according to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA). Across the multiple trials reviewed, Texture Profile Analysis and the Uniaxial Compression Test were most used as the instrumental technique for solid foods, and the Back Extrusion Test for fluid and semisolid foods. All trials used descriptive analysis as the sensory technique. However, the experimental conditions of the trials lacked standardization. Consequently, the results of the trials were not comparable. To properly characterize the texture of TMFs intended for OD by each technique, an international consensus is needed to establish standardized experimental conditions. Methods based on these techniques should also be validated by collaborative studies to verify repeatability, replicability, and reproducibility.

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.

Lung ultrasound in young children with neurological impairment: A proposed integrative clinical tool for deaeration-detection related to feeding

Infants and children with neurological impairment, such as cerebral palsy (CP), often experience abnormal ingestion functions, including oropharyngeal dysphagia and gastroesophageal reflux disease, which led to aspiration-related respiratory complications, morbidity, hospitalization, or death. There is a lack of evidence-based, repeatable, infant-friendly instrumental procedures to assess aspiration-risk in infants with CP or other neurological disorders, with also a lack of clinical assessment measures to support the use of more invasive diagnostic techniques. To this purpose, in the current study we explore the feasibility of lung ultrasound (LUS), to assess lung deaeration possibly related to aspiration during meal, in a cohort of 35 subjects affected by CP or other encephalopathies, and 10 controls in the same age-range. We coupled LUS procedure with meal caregiver administration for each child. Our results support the feasibility of this innovative approach in the clinical setting. Exploratory findings revealed a number of lung abnormalities likely related to abnormal ingestion function in subjects. Subgroup analyses revealed possible differences in LUS abnormalities between CP and other encephalopathies, possibly related to different mechanism of disease or dysfunction. Also, some evidences arose about the possible relationship between such LUS abnormalities and feeding and swallowing abilities in CP or other encephalopathies. LUS showed preliminarily feasibility and effectiveness in detecting meal-related LUS abnormalities in a dynamic manner in the clinical setting. This approach demonstrated usefulness as a potential tool for improving assessment and management in complex care of infants and young children with severe neurological disorders.

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.

Effect of commercially available thickening agents on ready-to-feed infant formulas

Because of the importance of providing the appropriate fluid consistency for effective management of swallowing problems (dysphagia) in infants, this project sought to determine the effect of three commercially available thickening agents on the resulting thickened consistencies of commonly prescribed, ready-to-feed infant formulas. Nine ready-to-feed infant formulas were thickened with three different thickening agents to nectar and honey consistencies following manufacturer's instructions and their resulting thickness was measured via line spread test (LST). The nine formulas with nothing added to them (thin liquids) and the 27 target-nectar and 27 target-honey samples together created 63 unique samples for comparison. A series of one-way analysis of variance analyses were conducted to determine if the resulting thickness (as measured by LST values) for target categories of nectar and honey consistencies was significantly influenced by the type of thickening agent used. The achieved thickness of the formula samples as measured by LST values was statistically significantly different for the three different types of thickening agents used to achieve a target nectar consistency, F (2, 24) = 15.55, p < .001, η p 2 = .709. Additionally, the achieved thickness of the formula samples was statistically significantly different for the three different types of thickening agents used to achieve a target honey consistency, F (2, 24) = 16.18, p < .001, η p 2 = .709. The results of this study reveal that the choice of thickening agent impacts the resulting thickness of ready-to-feed infant formula.

Infant-Driven Feeding Systems: Do They "Normalize" the Feeding Experience of Infants With Cleft Palate?

OBJECTIVE

To examine feeding skills of infants with cleft palate with or without cleft lip (CP±L) using infant-driven feeding systems compared to healthy controls on standard bottles.

DESIGN

Cross-sectional cohort.

SETTING

Large pediatric academic medical center in the Midwestern United States.

PARTICIPANTS

Infants with CP±L (n = 15) using the Dr. Brown's Specialty Feeding System and typically developing infants without CP±L (n = 15) using the Dr. Brown's Natural Flow Original or Options bottles.

MAIN OUTCOME MEASURE(S)

Bottle-feeding proficiency, duration, milk transfer, and signs of feeding difficulty.

RESULTS

Five-minute feeding proficiency differed significantly between groups with the control group taking 45% of the feed compared to 16% for the CP±L group on level 1 (P < .001) and 30% on level 2 (P < .001) nipples. Proportion of milk transfer was 96% ± 7% for controls and 75% ± 24% for the CP±L group (P = .013). Feeding duration (minutes) differed between the control group (13 ± 3) and the CP±L groups on each nipple level (level 1: 29 ± 16; P = .003; level 2: 32 ± 11; P = .001). Milk transfer rate (mL/min) was 9 ± 3 for control infants compared to 3 ± 1 for infants with CP±L on level 1 (P < .001) and 5 ± 1 on level 2 (P = .007). Coughing occurred in 40% of infants with CP±L and 27% of controls.

CONCLUSIONS

Even when using specialty bottles, infants with CP±L differ from noncleft infants in feeding proficiency, duration, and overall intake.

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.

Standard Recipes for the Preparation of Thickened Barium Liquids Used in the Diagnosis of Dysphagia

Barium sulfate is commonly used to prepare contrast media for videofluorograpy. The flow characteristics of thickened liquids formulated for oropharyngeal imaging are known to be greatly affected by the addition of barium. In this study, thickened barium liquids were prepared by mixing a commercial xanthan gum (XG)-based thickener (Visco-up^®) at different concentrations (0.1%-3.0%) with barium powder (Baritop HD^®), and differences in the viscosity between thickened non-barium and thickened barium liquids were investigated. In addition, the thickness levels of thickened barium liquids, which are based on the National Dysphagia Diet (NDD) and International Dysphagia Diet Standardization Initiative (IDDSI) guidelines, were classified by measuring the viscosity (NDD) and gravity flow through a syringe (IDDSI) with 0.1%-3.0% thickener concentrations. The apparent viscosity (η_a,50) values of thickened barium liquids were much higher than those of thickened non-barium liquids, indicating that the addition of barium to the XG-based thickener resulted in further thickening. Standard recipes for preparing thickened barium liquids with desirable thickness levels were also established, showing the different thickener concentrations corresponding to the different NDD and IDDSI levels.

Assessing the Breastfeeding Dyad: A Guide for Speech-Language Pathologists

Purpose

More than 80% of U.S. mothers initiate breastfeeding; for many of them, direct breastfeeding is an important goal. Speech-language pathologists (SLPs) who assess infants with feeding concerns, however, are generally much more familiar with assessing bottle-feeding. The purpose of this tutorial is to assist SLPs in building on their existing assessment skills in order to provide effective, evidence-based options for mothers who wish to breastfeed their infants.

Conclusion

SLPs can assist families in meeting their breastfeeding goals through effective assessment of breastfeeding dyads.

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.

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.

Development of International Terminology and Definitions for Texture-Modified Foods and Thickened Fluids Used in Dysphagia Management: The IDDSI Framework

Dysphagia is estimated to affect ~8% of the world's population (~590 million people). Texture-modified foods and thickened drinks are commonly used to reduce the risks of choking and aspiration. The International Dysphagia Diet Standardisation Initiative (IDDSI) was founded with the goal of developing globally standardized terminology and definitions for texture-modified foods and liquids applicable to individuals with dysphagia of all ages, in all care settings, and all cultures. A multi-professional volunteer committee developed a dysphagia diet framework through systematic review and stakeholder consultation. First, a survey of existing national terminologies and current practice was conducted, receiving 2050 responses from 33 countries. Respondents included individuals with dysphagia; their caregivers; organizations supporting individuals with dysphagia; healthcare professionals; food service providers; researchers; and industry. The results revealed common use of 3-4 levels of food texture (54 different names) and ≥3 levels of liquid thickness (27 different names). Substantial support was expressed for international standardization. Next, a systematic review regarding the impact of food texture and liquid consistency on swallowing was completed. A meeting was then convened to review data from previous phases, and develop a draft framework. A further international stakeholder survey sought feedback to guide framework refinement; 3190 responses were received from 57 countries. The IDDSI Framework (released in November, 2015) involves a continuum of 8 levels (0-7) identified by numbers, text labels, color codes, definitions, and measurement methods. The IDDSI Framework is recommended for implementation throughout the world.

Using fiberoptic endoscopic evaluation of swallowing to detect laryngeal penetration and aspiration in infants in the neonatal intensive care unit

OBJECTIVE

To evaluate the safety of fiberoptic endoscopic evaluation of swallowing (FEES) and the reliability of both FEES and a videofluoroscopic swallowing study (VFSS) in identifying laryngeal penetration and tracheal aspiration in infants under 3 months old in the neonatal intensive care unit (NICU).

STUDY DESIGN

Twenty-five infants at least 37 weeks postmenstrual age suspected of aspirating were assessed with FEES and VFSS. Complications, autonomic instability and vital signs before endoscope insertion and following FEES were documented. Blinded video recordings were coded by two reviewers to determine reliability.

RESULTS

We found no major complications or significant differences between FEES prefeeding and postfeeding vital signs, including respiratory rate, heart rate or oxygen saturation. FEES interrater reliability was 80% for both penetration and aspiration, compared with 87 and 90%, respectively, for VFSS.

CONCLUSION

FEES is safe and reliable in assessing laryngeal penetration and tracheal aspiration in NICU infants.

Effect of Time and Temperature on Thickened Infant Formula

BACKGROUND

Unlike adult populations, who primarily depend on liquids for hydration alone, infants rely on liquids to provide them with hydration and nutrition. Speech-language pathologists working within pediatric medical settings often identify dysphagia in patients and subsequently recommend thickened liquids to reduce aspiration risk. Caregivers frequently report difficulty attempting to prepare infant formula to the prescribed thickness.

MATERIALS AND METHODS

This study was designed to determine (1) the relationship between consistencies in modified barium swallow studies and thickened infant formulas and (2) the effects of time and temperature on the resulting thickness of infant formula. Prepackaged barium consistencies and 1 standard infant formula that was thickened with rice cereal and with 2 commercially available thickening agents were studied. Thickness was determined via a line spread test after various time and temperature conditions were met.

RESULTS

There were significant differences between the thickened formula and barium test consistencies. Formula thickened with rice cereal separated over time into thin liquid and solid residue. Formula thickened with a starch-based thickening agent was thicker than the desired consistency immediately after mixing, and it continued to thicken over time. The data from this project suggest that nectar-thick and honey-thick infant formulas undergo significant changes in flow rates within 30 minutes of preparation or if refrigerated and then reheated after 3 hours.

CONCLUSIONS

Additional empirical evidence is warranted to determine the most reliable methods and safest products for thickening infant formula when necessary for effective dysphagia management.

Understanding the Viscosity of Liquids used in Infant Dysphagia Management

When assessing swallowing in infants, it is critical to have confidence that the liquids presented during the swallow study closely replicate the viscosity of liquids in the infant's typical diet. However, we lack research on rheological properties of frequently used infant formulas or breastmilk, and various forms of barium contrast media used in swallow studies. The aim of the current study was to provide objective viscosity measurements for typical infant liquid diet options and barium contrast media. A TA-Instruments AR2000 Advanced Rheometer was used to measure the viscosity of five standard infant formulas, three barium products, and two breastmilk samples. Additionally, this study measured the viscosity of infant formulas and breastmilk when mixed with powdered barium contrast in a 20 % weight-to-volume (w/v) concentration. The study findings determined that standard infant formulas and the two breastmilk samples had low viscosities, at the lower end of the National Dysphagia Diet (NDD) thin liquid range. Two specialty formulas tested had much thicker viscosities, close to the lower boundary of the NDD nectar-thick liquid range. The study showed differences in viscosity between 60 % w/v barium products (Liquid E-Z-Paque(®) and E-Z-Paque(®) powder); the powdered product had a much lower viscosity, despite identical barium concentration. When E-Z-Paque(®) powdered barium was mixed in a 20 % w/v concentration using water, standard infant formulas, or breastmilk, the resulting viscosities were at the lower end of the NDD thin range and only slightly thicker than the non-barium comparator liquids. When E-Z-Paque(®) powdered barium was mixed in a 20 % w/v concentration with the two thicker specialty formulas (Enfamil AR 20 and 24 kcal), unexpected alterations in their original viscosity occurred. These findings highlight the clinical importance of objective measures of viscosity as well as objective data on how infant formulas or breastmilk may change in consistency when mixed with barium.

Implications of changing the amount of thickener in thickened infant formula for infants with dysphagia

When a dysphagic infant is prescribed thickened infant formula (TIF) as a treatment method, some clinicians determine their own addition rates of thickener to meet the specific needs of the infant rather than relying on the directions on the tin. In this study the rheological behaviour of a TIF at different addition levels of thickener was measured to determine whether there was a difference in full rheological response and in viscosity. In addition, the time taken for the TIF to reach a near-stable viscosity was also measured. One hundred grams of Karicare® infant formula was made up according to the manufacturer’s instructions and Karicare® feed thickener was added at levels of 2, 3, 4, 5, and 6 g, respectively. A strain-controlled rheometer (ARES) with Couette geometry was used to rheologically characterise the TIF at the different levels of thickener addition. There was a significant difference in viscosity between the low levels and the higher levels of addition thickener (p < 0.05). Also, the low levels of thickener addition showed Newtonian-like behaviour, whereas the higher levels of addition were shear-thinning. The time taken for the thickener to reach a near-stable viscosity was found to be 10 min. Guidelines for thickened infant formula need to take into account the different levels of thickener addition rates.

Feed-Thickening Practices in NICUs in the Current Era: Variability in Prescription and Implementation Patterns

BACKGROUND

Feed-thickening for infants in the Neonatal Intensive Care Unit (NICU) is performed due to concerns of dysphagia and gastroesophageal reflux disease (GERD). No standards currently exist regarding feed-thickening prescriptions and practices and this results in variable and potentially unsafe feeding approaches.

METHODS

Electronic surveys were sent to neonatal feeding therapists and providers in order to determine the prescriptions and practices currently being used for feed-thickening in the NICU.

RESULTS

A total of 313 responses were collected. Results revealed the majority of providers use thickened feeds for concerns of dysphagia or GERD with some reporting they thicken expressed breast milk. Variability of thickening prescriptions was noted regarding consistencies, thickening agents, and recipes used. Reported approaches for measuring, mixing, and warming thickened feeds varied.

CONCLUSION

Variability was noted in the feed-thickening prescriptions and practices performed in the NICU. Further research and standardization are required to develop thickening guidelines.

Pediatric Dysphagia: Physiology, Assessment, and Management

Infancy and childhood represent a time of unparalleled physical growth and cognitive development. In order for infants and children to reach their linear and neurological growth potential, they must be able to reliably and safely consume sufficient energy and nutrients. Swallowing difficulties (dysphagia) in pediatric populations can have a detrimental effect on dietary intake and, thus, growth and development. As a result, it is imperative to accurately identify and appropriately manage dysphagia in pediatric populations. This article provides an overview of dysphagia in children, as well as common causes of childhood swallowing difficulties, populations at risk for pediatric dysphagia, techniques used to assess swallowing in pediatric patients, and the current treatment options available for infants and children with dysphagia.

Viscosidade e qualidade da imagem do líquido espessado para videodeofluoroscopia de deglutição com acréscimo do contraste de bário

OBJETIVOS: estudar a viscosidade da fórmula de partida espessada para os exames de videofluoroscopia de deglutição após acréscimo de contraste de Bário. MÉTODOS: copos de 200 ml de leite foram preparados em três consistências com sete espessantes. A viscosidade média foi verificada com viscosímetro nas temperaturas ambiente e acima de 40ºC, e após acrescentar o contraste de Bário em diluições a 50%, 25% e 12,5%. Os preparados foram expostos à fluoroscopia para obtenção de imagens que foram avaliadas quanto à visualização do preparado nas diferentes consistências, diluições e espessantes. RESULTADOS: comparando valores médios em centipoise(cP), observou-se que a viscosidade na consistência pudim foi significantemente menor na temperatura acima de 40ºC do que na temperatura ambiente. Nas consistências néctar e pudim o acréscimo de Bário resultou em mudança significante da viscosidade para mel. Não houve mudança na qualidade das imagens entre as diluições de Bário à 50% e 25%. CONCLUSÃO: o acréscimo do Bário resulta em mudanças nos valores de viscosidade que afetaram a consistência do preparado espessado para néctar e pudim. Uma redução da diluição do contraste para 25% não resulta em mudança clinicamente significante na qualidade da imagem. Os achados sugerem a importância da padronização do preparado para a fluoroscopia em relação à viscosidade e diluição do Bário visando garantir a reprodutibilidade do exame, prevenir falhas diagnósticas e otimizar as orientações para modificações da dieta na disfagia orofaríngea infantil.

Use of Thickened Liquids to Manage Feeding Difficulties in Infants: A Pilot Survey of Practice Patterns in Canadian Pediatric Centers

Improved survival rates of sick or preterm infants have resulted in an increase of observed feeding difficulties. One common method for managing feeding difficulties in infants is to manipulate liquid viscosity by adding thickening agents to formula or expressed breast milk. Concerns regarding the lack of clinical practice guidelines for the use of this strategy have been raised in the literature and in clinical settings for several years. This study aimed to survey feeding clinicians working in major Canadian pediatric centers to identify current practice patterns for use of thickened liquids in managing feeding difficulties of infants and to justify the need for standardization of this practice. A web-based pilot survey was developed using Fluidsurveys software. The questionnaire contained 37 questions targeting the process of prescribing thickeners, choice of thickener, awareness of issues, and inconsistencies raised in the literature about thickener use and how to address them. A total of 69 questionnaire responses were analyzed using descriptive statistics and inductive thematic analysis methods. Our study results indicate that thickened liquids continue to be broadly used to manage feeding difficulties in Canadian infants, despite numerous areas of concern related to their use raised by our respondents. While clear practice patterns for assessment and management were observed among the respondents, some areas of practice did not reflect recent published research or experts' opinion. Further research to develop a systematic approach for assessment, intervention, and follow-up is warranted to guide clinicians in this complex decision-making process.

The influence of food texture and liquid consistency modification on swallowing physiology and function: a systematic review

Texture modification has become one of the most common forms of intervention for dysphagia, and is widely considered important for promoting safe and efficient swallowing. However, to date, there is no single convention with respect to the terminology used to describe levels of liquid thickening or food texture modification for clinical use. As a first step toward building a common taxonomy, a systematic review was undertaken to identify empirical evidence describing the impact of liquid consistency and food texture on swallowing behavior. A multi-engine search yielded 10,147 non-duplicate articles, which were screened for relevance. A team of ten international researchers collaborated to conduct full-text reviews for 488 of these articles, which met the study inclusion criteria. Of these, 36 articles were found to contain specific information comparing oral processing or swallowing behaviors for at least two liquid consistencies or food textures. Qualitative synthesis revealed two key trends with respect to the impact of thickening liquids on swallowing: thicker liquids reduce the risk of penetration-aspiration, but also increase the risk of post-swallow residue in the pharynx. The literature was insufficient to support the delineation of specific viscosity boundaries or other quantifiable material properties related to these clinical outcomes. With respect to food texture, the literature pointed to properties of hardness, cohesiveness, and slipperiness as being relevant both for physiological behaviors and bolus flow patterns. The literature suggests a need to classify food and fluid behavior in the context of the physiological processes involved in oral transport and flow initiation.

Swallowing kinematics and airway protection after palatal local anesthesia in infant pigs

OBJECTIVES/HYPOTHESIS

Abnormal kinematics during swallowing can result in aspiration, which may become life threatening. We tested the role of palatal sensation in the motor control of pharyngeal swallow in infants.

STUDY DESIGN

In eight infant pigs, we reduced palatal sensation using local anesthesia (PLA) and measured the impact on swallowing kinematics and airway protection.

METHODS

The pigs drank milk containing barium while we simultaneously recorded videofluoroscopy and electromyography from fine wire bipolar electrodes in several hyolaryngeal muscles. We compared these results to control feedings and feedings following palatal saline injections.

RESULTS

After PLA, four pigs had extreme jaw movements and abnormal tongue movement uncharacteristic of sucking. For this reason, we evaluated differences between these group B pigs and the others that could suck normally after PLA (group A). In the four group A pigs, after PLA there was less hyoid elevation (P < .001) but normal jaw and tongue movements. In group B, in addition to greater jaw movement (P < .001) there was more anterior and superior tongue movement (P < .001) and a larger range of hyoid movement (P < .001).

CONCLUSIONS

The airway was protected in all of the pigs, indicating that these changes allowed successful adaptation to the reduction in palatal sensation. However, the oral and pharyngeal phases of the swallow were functionally linked, and trigeminal sensation influenced the motor control of the pharyngeal swallow.

LEVEL OF EVIDENCE

N/A.

The Need for International Terminology and Definitions for Texture-Modified Foods and Thickened Liquids Used in Dysphagia Management: Foundations of a Global Initiative

Conservative estimates suggest that dysphagia (difficulty swallowing) affects approximately 8 % of the world's population. Dysphagia is associated with malnutrition, dehydration, chest infection and potentially death. While promising treatments are being developed to improve function, the modification of food texture and liquid thickness has become a cornerstone of dysphagia management. Foods are chopped, mashed or puréed to compensate for chewing difficulties or fatigue, improve swallowing safety and avoid asphyxiation. Liquids are typically thickened to slow their speed of transit through the oral and pharyngeal phases of swallowing, to avoid aspiration of material into the airway and improve transit to the esophagus. Food texture and liquid modification for dysphagia management occurs throughout the world. However, the names, the number of levels of modification and characteristics vary within and across countries. Multiple labels increase the risk to patient safety. National standardization of terminology and definitions has been promoted as a means to improve patient safety and inter-professional communication. This article documents the need for international standardized terminology and definitions for texture-modified foods and liquids for individuals with dysphagia. Furthermore, it documents the research plan and foundations of a global initiative dedicated to this purpose.

Sucking and swallowing rates after palatal anesthesia: an electromyographic study in infant pigs

Infant mammalian feeding consists of rhythmic suck cycles and reflexive pharyngeal swallows. Although we know how oropharyngeal sensation influences the initiation and frequency of suck and swallow cycles, the role of palatal sensation is unknown. We implanted EMG electrodes into the mylohyoid muscle, a muscle active during suckling, and the thyrohyoid muscle, a muscle active during swallowing, in eight infant pigs. Pigs were then bottle-fed while lateral videofluoroscopy was simultaneously recorded from the electrodes. Two treatments were administered prior to feeding and compared with control feedings: 1) palatal anesthesia (0.5% bupivacaine hydrochloride), and 2) palatal saline. Using the timing of mylohyoid muscle and thyrohyoid muscle activity, we tested for differences between treatment and control feedings for swallowing frequency and suck cycle duration. Following palatal anesthesia, four pigs could not suck and exhibited excessive jaw movement. We categorized the four pigs that could suck after palatal anesthesia as group A, and those who could not as group B. Group A had no significant change in suck cycle duration and a higher swallowing frequency after palatal saline (P = 0.021). Group B had significantly longer suck cycles after palatal anesthesia (P < 0.001) and a slower swallowing frequency (P < 0.001). Swallowing frequency may be a way to predict group membership, since it was different in control feedings between groups (P < 0.001). The qualitative and bimodal group response to palatal anesthesia may reflect a developmental difference. This study demonstrates that palatal sensation is involved in the initiation and frequency of suck and swallow cycles in infant feeding.

Evaluation of the uptake of the Australian standardized terminology and definitions for texture modified foods and fluids

This paper discusses the uptake of standardized terminology and definitions for texture modified foods and fluids. The Australian dietetic and speech-language pathology associations endorsed national standards in 2007. This project sought to determine the barriers and enablers for use of the national standards in clinical practice. Cross-sectional online surveys were developed, including open- and closed-response questions. The surveys targeted different professional groups in Australia including speech-language pathologists, dietitians, nurses, and food service personnel. Australian accredited universities were contacted to determine penetration of the standards. A total of 574 surveys were received. Sixty-five per cent of respondents indicated full implementation, 23% partial implementation, and 10% no implementation of the standards in their workplace. Speech-language pathologists and dietitians were most likely to have championed implementation of the standards. Barriers to implementation included: lack of knowledge about the standards, time, and resistance to change. Enablers included: encouragement to use the standards and 'buy-in' from stakeholders. Benefits of implementation included: consistent terminology and perceived improvements in patient safety. It was concluded that the standards have been successfully implemented in a majority of facilities and Australian universities. This study provides insight into the complexity of introducing and managing change in healthcare environments.