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

The nutrition profile and utility of banana puree as a liquid thickener for medically complex infants with dysphagia

INTRODUCTION

Dysphagia among infants, particularly high-risk and preterm neonates, poses feeding challenges that can impact multiple systemic outcomes and delay hospital discharge. Limited therapeutic options for approved thickening agents for human milk and infant formula necessitate the exploration of alternatives, including banana puree.

METHOD

This study investigated the feasibility of using banana puree as a thickening agent for hospitalized infants with dysphagia. The International Dysphagia Diet Standardisation Initiative (IDDSI) flow test determined optimal volumes of banana puree mixed with infant formulas or human milk to achieve desired liquid thickness levels. Nutrition analysis considered potassium intake and calories from carbohydrates to assess dietary composition.

RESULT

Banana puree effectively achieved IDDSI Levels 1-3, with varying volumes required based on milk types and caloric concentrations. The nutrition analysis revealed the importance of restricting banana puree to 15% of feeding volumes to avoid exceeding recommended potassium levels while promoting appropriate nutrition.

CONCLUSION

Banana puree represents a promising option for thickening feeds in infants with dysphagia, facilitating safe oral feeding opportunities, accelerating the introduction of oral feeding, and, potentially, improving long-term outcomes. Further research is warranted to explore its impact on feeding progression, hospital stays, growth, patient outcomes, and feeding-related behaviors compared with traditional thickening agents.

Oropharyngeal swallowing hydrodynamics of thin and mildly thick liquids in an anatomically accurate throat-epiglottis model

Understanding the mechanisms underlying dysphagia is crucial in devising effective, etiology-centered interventions. However, current clinical assessment and treatment of dysphagia are still more symptom-focused due to our limited understanding of the sophisticated symptom-etiology associations causing swallowing disorders. This study aimed to elucidate the mechanisms giving rise to penetration flows into the laryngeal vestibule that results in aspirations with varying symptoms. Methods: Anatomically accurate, transparent throat models were prepared with a 45° down flapped epiglottis to simulate the instant of laryngeal closure during swallowing. Fluid bolus dynamics were visualized with fluorescent dye from lateral, rear, front, and endoscopic directions to capture key hydrodynamic features leading to aspiration. Three influencing factors, fluid consistency, liquid dispensing site, and dispensing speed, were systemically evaluated on their roles in liquid aspirations. Results: Three aspiration mechanisms were identified, with liquid bolus entering the airway through (a) the interarytenoid notch (notch overflow), (b) cuneiform tubercle recesses (recess overflow), and (c) off-edge flow underneath the epiglottis (off-edge capillary flow). Of the three factors considered, liquid viscosity has the most significant impact on aspiration rate, followed by the liquid dispensing site and the dispensing speed. Water had one order of magnitude higher aspiration risks than 1% w/v methyl cellulose solution, a mildly thick liquid. Anterior dispensing had higher chances for aspiration than posterior oropharyngeal dispensing for both liquids and dispensing speeds considered. The effects of dispending speed varied. A lower speed increased aspiration for anterior-dispensed liquids due to increased off-edge capillary flows, while it significantly reduced aspiration for posterior-dispensed liquids due to reduced notch overflows. Visualizing swallowing hydrodynamics from multiple orientations facilitates detailed site-specific inspections of aspiration mechanisms.

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.

Testing and Development of Slightly Thick Infant Formula Recipes for Dysphagia Management: An Australian Perspective

Thickened feeds may be useful in supporting improved suck-swallow-breath coordination and airway protection in infants with dysphagia. Unfortunately, the stability of thickened feeds for infant formulas is unpredictable, which makes use of this strategy challenging. This study aimed to propose a set of Level 1 (slightly thick) recipes for Australian infant formulas/thickeners. A secondary aim was to test whether formula could be batch prepared. A set of powdered, ready-to-feed, and specialized formulas were mixed with two thickening products (Aptamil Feed Thickener® and Supercol®) and tested at 5-, 10-, 15-, 20-, 25-, 30-, and 45-min intervals using the International Dysphagia Diet Standardization Initiative (IDDSI) Flow Test. Formula/thickener samples were mixed following manufacturer instructions, but recipes were adapted to determine an ideal recipe for Level 1 (slightly thick) consistency that would be maintained over a feed. Samples were refrigerated, reheated after 12 h, and retested. Each combination was tested six times. Overall, 1,353 IDDSI Flow Tests were conducted using 14 formula/thickener combinations. In all combinations, recipe alterations were made using metric spoon measurements as opposed to the manufacturer-provided scoop. All samples were most variable at the 5-min timepoint. Formulas thickened with Supercol® generally reached a more stable consistency by 10 min, whereas formulas thickened with Aptamil Feed Thickener® were more stable by 15 min. Samples tested after 12 h were more variable with Aptamil Feed Thickener®. This study provides practical recommendations for clinicians working with infants requiring thickened feeds for dysphagia management. Further study under controlled laboratory conditions is required.

Clinical Focus: Findings and Clinical Implications for Thickening Formula With Infant Cereal Using the International Dysphagia Diet Standardisation Initiative Flow Test

PURPOSE

The International Dysphagia Diet Standardisation Initiative (IDDSI) framework was established to provide standardized terminology and objective measures to assess foods and liquids for persons with swallowing difficulties. This clinical focus article reports the findings and clinical implications of the flow testing of infant formulas thickened with infant cereal completed as part of the transition process to IDDSI for one large pediatric quaternary care hospital.

METHOD

To determine a common recipe that could be used to thicken formulas with infant cereal to the appropriate IDDSI levels, three clinicians completed flow testing on 94 infant formulas. To examine intra- and interclinician variability in the process, they repeated flow testing with three commonly used formulas and infant cereal.

RESULTS

Clinicians were unable to identify a standard recipe (infant formula + infant cereal combination) that consistently thickened different formula brands to a desired IDDSI thickness level, as there was pronounced variability across and within infant formulas. Reliability testing revealed that, overall, clinician mixers were consistent in replicating similar results to themselves and to each other and that, instead, greater variability lies within the formula (and infant formula + infant cereal combination).

CONCLUSIONS

Based on findings of pronounced variability within and across infant formulas, our institution determined that the creation of a standard recipe for achieving IDDSI thickness levels of formula mixed with infant cereal was not feasible or clinically appropriate. We offer recommendations for similar institutions for advancing clinical management of infant dysphagia using the IDDSI flow test and directions for future research.