Use of Textured Thin Liquids in Patients With Dysphagia

Effect of a texture-modified and controlled bolus volume diet on all-cause mortality in older persons with oropharyngeal dysphagia: Secondary analysis of a randomized controlled trial

BACKGROUND

Oropharyngeal dysphagia (OD) is common among older adults. Some studies have evaluated the efficacy of a texture-modified diet on mortality but with short-term follow-up. We aimed to evaluate the effect of a texture-modified diet and controlled bolus volume on all-cause mortality after 12 months in older persons with OD.

METHODS

This secondary analysis of a randomized clinical trial included patients aged ≥60 years with a diagnosis of OD. They were concurrently and randomly assigned to receive either a texture-modified food diet and controlled bolus volume (intervention group) or standard treatment (control group) with 12 months of follow-up. Secondary outcomes were oral intake, weight, handgrip strength, phase angle, and aspiration pneumonia. Kaplan-Meier analysis and the Cox proportional hazards model were used for mortality analysis.

RESULTS

A total of 127 participants (intervention group: 64 and control group: 63) were recruited, with a mean age of 76 years. The probability of all-cause mortality was significantly lower in the intervention group (n = 8, 12%) than in the control group (n = 18, 29%) (hazard ratio = 0.36 [95% CI = 0.16-0.86]; P = 0.01). There were 5 (7.9%) and 10 (16.1%) aspiration pneumonia events in the intervention and control groups, respectively (not significant) in 12 months of follow-up. Changes were observed in protein consumption (P = 0.01), body weight (P = 0.04), body mass index (P = 0.004), handgrip strength (P = 0.02), and phase angle (P = 0.04) between the treatment groups.

CONCLUSION

Compared with the standard treatment, the dietary intervention improved efficacy by limiting nutrition complications, aspiration pneumonia, and all-cause mortality.

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 Adverse Effects and Events of Thickened Liquid Use in Adults: A Systematic Review

PURPOSE

Practice pattern studies suggest that liquid modification is currently a primary strategy used by speech-language pathologists to manage dysphagia; however, the breadth of negative consequences associated with their use is not well understood. The purpose of this review was to summarize the evidence on adverse events and effects of thickened liquid (TL) use in adults.

METHOD

Six databases were searched in February 2022: EMBASE, MEDLINE (PubMed), Speechbite, AMED, AgeLine, and CINAHL. Articles were included if they compared adults receiving different TL viscosities and discussed at least one adverse event or effect of consuming TLs. Articles were excluded if they were review articles, rehabilitation studies, rheological analyses, not in English, or not peer reviewed. Screening and data extraction were completed by two independent reviewers. Risk of bias was assessed using Cochrane tools.

RESULTS

Thirty-three studies (N = 4,990 participants across all studies) were eligible for inclusion (2,405 unique records screened). Reported adverse events included dehydration (n = 5), pneumonia (n = 4), death (n = 2), urinary tract infection (n = 1), and hospitalization (n = 1); adverse effects included reduced quality of life (n = 18), aspiration (n = 12), reduced intake (n = 8), increased residue (n = 4), and reduced medication bioavailability (n = 2). Results were mapped on to codes and domains of the International Classification of Functioning, Disability and Health.

CONCLUSIONS

A range of adverse outcomes associated with TL use were identified. Adverse outcomes should be monitored and reported in dysphagia research. Given current research evidence, it is vital for clinicians to weigh the risks and benefits of TL use to mitigate potential adverse outcomes.

The Hydration Status of Adult Patients with Oropharyngeal Dysphagia and the Effect of Thickened Fluid Therapy on Fluid Intake and Hydration: Results of Two Parallel Systematic and Scoping Reviews

BACKGROUND

The effect of oropharyngeal dysphagia (OD) and thickened fluid (TF) therapy on hydration status has not been well defined in the literature. We aimed to assess the hydration status in patients with OD and the effect TF therapy has on it.

METHODS

Two literature reviews following PRISMA methodology (each one including a systematic and a scoping review) were performed: (R1) hydration status in adult patients with OD; (R2) effect of TF therapy on fluid intake and dehydration. Narrative and descriptive methods summarized both reviews. Quality assessment was assessed by Joanna Briggs Institute tools and GRADE.

RESULTS

(R1) Five out of twenty-two studies using analytical parameters or bioimpedance showed poorer hydration status among OD and 19-100% prevalence of dehydration; (R2) two high quality studies (total of 724 participants) showed positive effects of TF on hydration status. Among the articles included, nine out of ten studies that evaluated fluid intake reported a reduced TF intake below basal water requirements.

CONCLUSIONS

Dehydration is a highly prevalent complication in OD. There is scientific evidence on the positive effect of TF therapy on the hydration status of patients with OD. However, strict monitoring of fluid volume intake is essential due to the low consumption of TF in these patients.

Interventions to Improve Hydration in Older Adults: A Systematic Review and Meta-Analysis

Dehydration is common in the elderly, especially when hospitalised. This study investigated the impact of interventions to improve hydration in acutely unwell or institutionalised older adults for hydration and hydration linked events (constipation, falls, urinary tract infections) as well as patient satisfaction. Four databases were searched from inception to 13 May 2020 for studies of interventions to improve hydration. Nineteen studies (978 participants) were included and two studies (165 participants) were meta-analysed. Behavioural interventions were associated with a significant improvement in hydration. Environmental, multifaceted and nutritional interventions had mixed success. Meta-analysis indicated that groups receiving interventions to improve hydration consumed 300.93 mL more fluid per day than those in the usual care groups (95% CI: 289.27 mL, 312.59 mL; I² = 0%, p < 0.00001). Overall, there is limited evidence describing interventions to improve hydration in acutely unwell or institutionalised older adults. Behavioural interventions appear promising. High-quality studies using validated rather than subjective methods of assessing hydration are needed to determine effective interventions.

The care needs of persons with oropharyngeal dysphagia and their informal caregivers: A scoping review

INTRODUCTION

Besides affecting physical health, Oropharyngeal Dysphagia (OD) entails limitations in daily activities and social participation for both patients and their informal caregivers. The identification of OD-related needs is crucial for designing appropriate person-centered interventions.

AIMS

To explore and map the literature investigating the care needs related to OD management of adult persons with OD and their informal caregivers during the last 20 years.

METHODS

A scoping review was conducted and reported following PRISMA guidelines. Five electronic databases and reference lists of eligible publications were searched for original works in English or Italian, published between January 2000 and February 2021. Two independent raters assessed studies' eligibility and extracted data; a third rater resolved disagreements. Extracted care needs were analyzed using a Best fit framework synthesis approach.

RESULTS

Out of 2,534 records preliminarily identified, 15 studies were included in the review and 266 care needs were extracted. All studies were conducted in Western countries. Research methods primarily consisted of qualitative interviews and focus groups (14 studies, 93.3%); head and neck cancer was the most frequent cause of patients' dysphagia (8 studies, 53.3%); caregivers' perspective was seldom investigated (5 studies, 33.3%). Both patients and caregivers primarily reported social (N = 77; 28.9%) and practical (N = 67; 25.2%) needs, followed by informational (N = 55; 20.7%) and psychological (N = 54; 20.3%) ones. Only patients reported physical needs (N = 13; 4.9%), while spiritual needs were not cited.

CONCLUSIONS

The recurrence of personal and social needs besides physical ones highlighted the manifold impact of OD on patients' and caregivers' lives. Larger and more focused studies are required in order to design tools and interventions tailored to patients' and caregivers' needs.

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

PURPOSE OF REVIEW

The use of commercially or naturally thickened liquids is a well-established treatment for patients with dysphagia to fluids, the aim of which is to improve swallow safety by minimizing risk of aspiration. Although the most recent systematic reviews conclude that this treatment lacks evidential support and leads to patient-reported worsening health and quality of life, thickened liquids continue to be used with patients with dysphagia across clinical settings. This review briefly summarizes the evidence and considers potential reasons for the apparent mismatch between the evidence and clinical practice.

RECENT FINDINGS

Continuing practice with thickened liquids is influenced by a range of factors, including gaps in clinical knowledge, inadequate patient involvement, a culture of common practice and a reliance on invalid surrogate studies or research lacking a credible association between thickened liquids and clinically meaningful endpoints.

SUMMARY

While awaiting further research, clinical decision-making about thickened liquids can be improved by considering the evidence of clinically meaningful endpoints, promoting shared decision-making with patients and underpinning practice with knowledge about the complex relationship between dysphagia, aspiration and pneumonia.

The impact of modification techniques on the rheological properties of dysphagia foods and liquids

Modifying food and the textures of food has been done for decades within the food science and technology field. More recently, modifying the texture of foods has been used to manage swallowing disabilities (dysphagia). Swallowing disabilities are often associated with dehydration and malnutrition, thus nutritional intervention has formed part of serving texture-modified diets. The question remains whether these modification techniques are viable for individuals with swallowing disabilities living in majority world countries. This study used two modification methods on a widely used specialized nutritious food (SNF) to determine whether it may be modified and used in dysphagia management. The techniques had to be ergonomic and economically appropriate for individuals with swallowing disabilities living in majority world countries. The International Dysphagia Diet Standardization Initiative's (IDDSI) standards were used to determine whether the texturally modified SNF is safe for swallowing. Rheological measurements were performed to determine apparent viscosity and structure recovery of each sample. The effects of two modification techniques, aeration and particle separation, on the rheological properties of the SNF were also measured and analyzed. It was determined that both milk and water could be used with this SNF to create a dysphagia diet, but only under certain conditions. The overall results indicated that heating the samples increased the apparent viscosity and exacerbated lumping. Room temperature samples had less lumps and could be classified to the desired levels of the IDDSI (Level 2 and Level 4). Using a whisk to aerate the samples reduced lumps significantly and using a sieve to separate particles of liquid samples eliminated lumps. This study provides new data on how texture modification techniques and the IDDSI framework could be adapted to individuals living in majority world countries. By using modification techniques that are ergonomic and economically viable and an SNF with longevity, this study could be useful in guiding future training of nursing staff and caregivers of individuals living in poverty or resource-constrained communities. This study also adds to the data on the rheological properties of dysphagia foods, although this study did not make use of commercial thickeners generally used in the modification of diets.