Promoting Safe Swallowing When Puree is Swallowed Without Aspiration but Thin Liquid is Aspirated: Nectar is Enough

Effects of Thickening Agents on the Mucociliary Transport Function: Comparison by the Type of Thickening Agents and the Viscosity of Thickened Water

Thickening agents effectively prevent liquid aspiration, but their impact on the ease of discharging aspirated liquids from the trachea remains unclear due to alterations in the physical properties of liquids. This study clarifies the effects of thickening agents, comprising various raw materials, on mucociliary transport function, focusing on the viscosities of thickened waters. The subjects were 23 healthy adults. Five types of saccharin solution were prepared: a solution without a thickening agent, a starch-based nectar-like solution, a starch-based honey-like solution, a xanthan-gum-based nectar-like solution, and a xanthan-gum-based honey-like solution. Using these five types of saccharin solutions randomly, each subject underwent five trials of the saccharine dye test to evaluate the mucociliary transport function of the respiratory tract. The saccharin time was defined as the time from the placement of the saccharin solution on the nasal vestibule of the subject to when the subject reported that they became aware of the sweetness. The saccharin transit times for all samples of thickened water were longer compared to those of water without a thickening agent (p < 0.01). A comparison between thickened water samples with different viscosities showed that the saccharin transit time was longer when thickened water samples with high viscosity were prepared using the same thickening agent (p < 0.01). This suggests that while thickening reduces aspiration, the use of thickening agents may increase the difficulty in discharging aspirated fluids from the trachea.

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).

Does oral intake of thin fluids increase aspiration pneumonia for dysphagia after head and neck cancer surgery? A retrospective study for a total of 654 cases

OBJECTIVE

Head and neck cancer (HNC) treatment causes dysphagia, which may lead to aspiration pneumonia (AP). Thickened fluids are widely used to prevent aspiration in patients with dysphagia; however, there is little evidence that they can prevent AP. This study aimed to clarify the differences between restriction of oral intake of fluids (R), only thickened fluids (TF), and no restriction of fluids (NR) for AP in patients with dysphagia after HNC treatment.

METHODS

We retrospectively studied 654 patients with dysphagia after HNC surgery between 2012 and 2021. Of these, 255 had some restriction of fluids. The development of possible AP and administration of antibacterial drugs were used as outcomes. Multivariate linear regression and propensity score matching analyses were performed.

RESULTS

The mean patient age was 64 ± 13, 67 ± 11, and 68 ± 10 years, while the Dynamic Imaging Grade of Swallowing Toxicity score 3-4 was 2.8%, 27.5, and 53.3%% water in NR, TF, and R groups, respectively. AP was diagnosed or suspected after starting oral intake in 37 (9.3%), 11 patients (15.9%), and 45 (17.6%) and antibacterial drugs were administered in 11 (2.8%), 7 patients (10.1%), and 25 (9.8%) in NR, TF, and R groups, respectively. R and TF had significant negative impacts on AP.

CONCLUSIONS

Fluid restrictions may not reduce the risk of AP or affect the administration of antibacterial drugs. Medical staff should bear in mind that fluid restrictions do not necessarily prevent AP in patients with HNC.

Adapting the International Dysphagia Diet Standardisation Initiative in East Asia: Feasibility study

In dysphagia, food or water cannot be delivered safely through the oral cavity to the stomach; both are treated using texture-modified food and thickened fluid. Before, each country had its own diet modifications and texture measurement standards. In 2012, the International Dysphagia Diet Standardisation Initiative (IDDSI) was developed by several countries. Owing to cultural differences, it was necessary to determine whether the IDDSI could well be applied to clinicians and patients without difficulties in East Asia countries. To evaluate the IDDSI scale to find out the difficulties applying this scale in East Asia countries to educate the clinicians and patients. In May 2021, we enrolled physicians, nurses, nutritionists, and swallowing therapists involved in dysphagia treatment at a single center in Seoul. To evaluate the degree of understanding and difficulties of adapting IDDSI to clinicians in East Asia countries, we used the 17-item questionnaire with IDDSI sample foods and foods in Asian countries. In first 7 items, we compared IDDSI with the previously used scale based on the National Dysphagia Diet (NDD). In the next 10 questions, only the IDDSI levels were answered, and the absolute values of the answer-response differences were calculated. The IDDSI showed a significantly high intraclass correlation with the previously used NDD-based scale; the coefficient was higher for the nutritionists (0.988) and swallowing therapists (0.991). When evaluating whether the IDDSI could applied well in East Asia countries, the absolute values of the answer-response differences were lower than 0.5 in majority of levels, except for Level 4. Because the IDDSI framework might successfully be applied universally regardless of food culture, a worldwide standard for food rheology in dysphagia treatment might be possible.

Effects of Food and Liquid Properties on Swallowing Physiology and Function in Adults

Foods and liquids have properties that are often modified as part of clinical dysphagia management to promote safe and efficient swallowing. However, recent studies have questioned whether this practice is supported by the evidence. To address this, a scoping review was conducted to answer the question: "Can properties of food and liquids modify swallowing physiology and function in adults?" Online search in six databases yielded a set of 4235 non-duplicate articles. Using COVIDENCE software, two independent reviewers screened the articles by title and abstract, and 229 full-text articles were selected for full-text review. One-hundred eleven studies met the inclusion criteria for qualitative synthesis and assessment of risk of bias. Three randomized controlled trials and 108 non-randomized studies were analyzed. Large amounts of variability in instrumental assessment, properties of food and liquids, and swallowing measures were found across studies. Sour, sweet, and salty taste, odor, carbonation, capsaicin, viscosity, hardness, adhesiveness, and cohesiveness were reported to modify the oral and pharyngeal phase of swallowing in both healthy participants and patients with dysphagia. Main swallow measures modified by properties of food and liquids were penetration/aspiration, oral transit time, lingual pressures, submental muscle contraction, oral and pharyngeal residue, hyoid and laryngeal movement, pharyngeal and upper esophageal sphincter pressures, and total swallow duration. The evidence pooled in this review supports the clinical practice of food texture and liquid consistency modification in the management of dysphagia with the caveat that all clinical endeavors must be undertaken with a clear rationale and patient-specific evidence that modifying food or liquid benefits swallow safety and efficiency while maintaining quality of life.

Compliance and effect of thickener use in dysphagia patients with brain lesions: An observational pilot study

The study aimed to investigate the status of thickener use in dysphagia patients with brain lesions and incidence of adverse events based on fluid viscosity. Twenty dysphagia patients with brain lesions who were recommended to use thickeners following a videofluoroscopic swallowing study were enrolled in this observational pilot study. Patients were educated to use thickener as level 2 or 3 based on the International Dysphagia Diet Standardization Initiative flow test. We evaluated the viscosity of the fluid that patients drank once a week for 2 weeks, and reviewed medical records regarding adverse events. Patients were divided into 2 groups based on the average value obtained from the viscosity evaluations as thin (Levels 0-2) and thick fluid groups (Levels 3-4). Adverse events were compared between the groups. The number of patients who did not follow the recommendations increased from 35.0 to 45.0% during the 1-week follow-up period. No patient developed pneumonia or urinary tract infection. Constipation (P = 0.338) and dehydration status (P = 0.202) were not significantly different between the 2 groups. In 2 evaluations for 20 patients, 40.0% of the cases did not follow the educated viscosity, and the number gradually increased in the follow-up evaluation. Considering that there were no significant differences in the incidence of adverse effects including pneumonia according to the fluid viscosity, a further study is necessary to establish detailed criteria for thickener use in dysphagia patients with brain lesions.

Advances in 3D printing of food and nutritional products

The main advantage of both 3D printing (3DP) and 3D food printing (3DFP) over other technologies is the enormous capacity of both techniques for customization. Its use makes it possible to obtain products without planning and implementing a complex and costly manufacturing process. This makes 3DFP a technology of choice for the preparation of food products that meet specific needs, such as controlled nutritional or rheological properties. However, further technological developments are still needed before 3DFP can be considered fully useful for innovative and demanding applications. If both preparation and post-processing of materials based on 3D printing are optimized, aiming to reduce production time and/or complication for non-expert users, this would open a whole new range of possibilities. It is in this sense that the development of advanced 3DFP systems becomes a must. This chapter reviews current advances in extrusion-based 3D food printing systems, with in situ gelation and mixing as key aspects to better exploit the potential of 3DFP. On one hand, 3DFP systems based on in situ gelation (G3DFP) provide greater control over the final properties of the printed products, as the selection of adequate printing parameters gives the possibility of influencing the gelation process. On the other hand, mixing is indispensable for true 3DFP automation, so that the formulations do not have to be prepared by the user. Different innovative 3DFP systems based on gelling and/or mixing are presented in this chapter. Finally, the status and future of extrusion-based 3DFP, and its application in the production of customized foods for specific needs, are also overviewed.

Structural Connectivity Affecting Aspiration After Stroke

Aspiration after stroke is associated with pneumonia and mortality. In this study, we investigated brain structural connectivity associated with aspiration after unilateral supratentorial stroke. Patients on oral feeding after stroke were divided into liquid aspiration (22 patients) and normal (18 patients) groups based on videofluoroscopic swallowing studies. Voxel-based lesion-symptom mapping and voxel-wise group comparison of fractional anisotropy, mode of anisotropy, and mean diffusivity maps were conducted. Voxel-based lesion-symptom mapping revealed no significant lesion differences between groups. The aspiration group showed significantly increased fractional anisotropy and mode of anisotropy in the anterior limb and the genu of the internal capsule in the right hemisphere. In contrast, the normal group showed significantly increased mean diffusivity, mainly in the superior longitudinal fasciculus in the right hemisphere (P < 0.05). Degeneration of the internal capsule in the right hemisphere was found to affect aspiration after stroke.

Treatment burden associated with the intake of thickened fluids

The implementation of thickened fluids in patients with dysphagia is widely considered an effective strategy for safe and physiologically improved swallow. However, there is limited evidence to suggest that this intervention reduces the risk of dysphagia-related complications including aspiration pneumonia. In addition, there is growing evidence that this approach is associated with adverse clinical effects including dehydration, malnutrition and reduced health-related quality of life. This review summarises the rationale for thickened fluids, the evidence base (or lack thereof) underpinning their use, and current guideline recommendations.

Educational aims

To review the evidence base for thickened fluids in the management of dysphagia.To examine the evidence that thickened fluids reduce aspiration pneumonia.To provide an overview of the advantages and disadvantages of thickened fluids in the management of dysphagia.

Riluzole Oral Suspension for the Treatment of Amyotrophic Lateral Sclerosis: Texture and Compatibility with Food Thickeners Evaluation

Riluzole 5 mg/mL oral suspension is the only licensed liquid medicine to treat Amyotrophic Lateral Sclerosis (ALS) orally. As more than 80% of ALS patients develop dysphagia, an oral liquid formulation provides an important therapeutic option. The Riluzole 5 mg/mL oral suspension is administered by means of the graduated oral dosing syringe included in the medicine package. Its concentration (5 mg/mL) is consistent with a small and easy to measure volume (10 mL) to deliver the prescribed 50-mg dose twice daily. This work had a dual objective. The first was to evaluate the texture of the Riluzole 5 mg/mL oral suspension according to the International Dysphagia Diet Standardisation Initiative (IDDSI) flow test. Results of this experiment indicated that Riluzole 5 mg/mL oral suspension would basically fall under the “mildly thick” IDDSI descriptors. This is an important feature because thick fluids facilitate a safer swallow in patients with dysphagia. As a second objective, we evaluated for scientific purposes the compatibility of Riluzole 5 mg/mL oral suspension with some of the most common food thickeners available on the market. Intimate mixtures of the Riluzole 5 mg/mL oral suspension with thickeners were evaluated for appearance, pH, Riluzole assay and Riluzole related substances immediately after preparation and after two hours at room temperature. Riluzole 5 mg/mL oral suspension resulted to be compatible with all the marketed thickeners tested.

Incremental Adjustments to Amount of Thickening Agent in Beverages: Implications for Clinical Practitioners Who Oversee Nutrition Care Involving Thickened Liquids

This study examined the changes in viscosity in response to small alterations in the amount of a thickening agent mixed with three commonly thickened beverages. A total of 11 incremental adjustments in the amount of a starch-based thickening agent (5.0 g to 7.0 g) were made. The results showed that the incremental increases resulted in systematic changes to the liquid thickness, reflecting modifications that ranged from a nectar (mildly thick) to a honey-like (moderately thick) level of consistency. The findings emphasize the importance of the proper preparation of thickened beverages, highlighting the need for standards in training practices and the use of simple measurement tools for assuring the prescribed levels of consistency.

Swallowing Kinematic Differences Across Frozen, Mixed, and Ultrathin Liquid Boluses in Healthy Adults: Age, Sex, and Normal Variability

PURPOSE

The aim of this study was to examine the effects of frozen and mixed-consistency boluses on the swallowing physiology of younger and older adults. We also aimed to quantify factors that lead to increased variability in swallowing outcomes (i.e., age, sex, bolus type).

METHOD

Forty-one healthy adults (18-85 years old) swallowed 5 blocks of 5 different boluses: 10-ml ultrathin liquid, a teaspoon of iced barium, a teaspoon of room-temperature pudding, a teaspoon of frozen pudding, and ultrathin barium with chocolate chips. All data were recorded with videofluoroscopy and underwent detailed timing kinematic measurements.

RESULTS

Neither barium ice nor frozen pudding sped up swallow responses. Many healthy adults initiated swallowing with the bolus as deep as the pyriform sinuses. Swallowing temporal kinematics for ultrathin liquid consistencies are most different from all others tested, requiring the best possible physiological swallowing performance in younger and older healthy individuals (i.e., faster reaction times, longer durations) compared with other bolus types tested. In each measure, older adults had significantly longer durations compared with the younger adults. More variability in swallowing kinematics were seen with age and laryngeal vestibule kinematics.

CONCLUSION

This study provides important contributions to the literature by clarifying normal variability within a wide range of swallowing behaviors and by providing normative data from which to compare disordered populations.

Visualizing the Consistency of Thickened Liquids With Simple Tools: Implications for Clinical Practice

PURPOSE

Accurate texture modifications to thin liquids are a critical aspect of patients' nutritional health and well-being. This study explored the use of 3 tools (2 distance- and 1 time-measuring devices) to characterize texture-modified liquids. The objectives were to use the tools to measure modified liquids, to determine if measurements differentiated nectar and honey levels of modification, and to compare measurements with other published reports.

METHOD

We measured the flow distance of 33 prethickened water samples in centimeters (cm) using a line spread apparatus and a Bostwick Consistometer (Christison Particle Technologies). We selected a Zahn viscosity cup to measure the stream time of each prethickened liquid in seconds.

RESULTS

The 2 distance-measuring devices (line spread and Bostwick Consistometer) showed that thinner (nectar-thick) modifications spread or flowed a farther distance in comparison to thicker (honey-like) modifications. Testing with the line spread indicated that an average spread distance of 4.5 cm differentiated nectar-thick and honey-like consistencies. A flow distance of greater than 15 cm differentiated nectar from honey consistency measured with a Bostwick Consistometer. We were not successful in using the Zahn viscosity cup to determine the stream time of modified liquids.

CONCLUSIONS

Two of the tools provided objective information about levels of liquid modification, which has implications for day-to-day preparation. Measurement tools that are accurate and easy to use have the potential to provide quick and dependable feedback to verify a prescribed level of liquid modification. Further efforts are needed to standardize the application of simple measurement tools in the management of patients who consume thickened liquids.

Texture-modified food and fluids in dementia and residential aged care facilities

INTRODUCTION

Dysphagia is common in people living with dementia and associated with increased risk of aspiration pneumonia, dehydration, malnutrition, and death. Treatment options are limited and the use of texture-modified food and fluids (TMF) is a widespread clinical practice. This review aimed to evaluate the evidence for TMF in dementia.

METHODS

A literature search using terms "dysphagia," "texture-modified food and fluids," "dementia," and "aged care" was performed by using three electronic databases from 1990 to March 2017. Studies were assessed for suitability, then reviewed with data extracted, and grouped by categories of outcome measures.

RESULTS

A total of 3,722 publications were identified, and 22 studies met the inclusion criteria. Studies were heterogeneous in design and methodology. There were no publications examining dementia exclusively; however, many subjects with dementia were included in studies of residential aged care facilities. TMF reduced the risk of aspiration seen on videofluoroscopy but not clinical aspiration and pneumonia. TMF was associated with lower daily energy and fluid intake and variable adherence.

CONCLUSION

There is a lack of evidence for people living with dementia and in residential care facilities that TMF improves clinical outcomes such as aspiration pneumonia, nutrition, hydration, morbidity, and mortality. Adverse effects including poorer energy and fluid intake were identified.

Identification of Swallowing Tasks From a Modified Barium Swallow Study That Optimize the Detection of Physiological Impairment

PURPOSE

The purpose of this study was to identify which swallowing task(s) yielded the worst performance during a standardized modified barium swallow study (MBSS) in order to optimize the detection of swallowing impairment.

METHOD

This secondary data analysis of adult MBSSs estimated the probability of each swallowing task yielding the derived Modified Barium Swallow Impairment Profile (MBSImP™©; Martin-Harris et al., 2008) Overall Impression (OI; worst) scores using generalized estimating equations. The range of probabilities across swallowing tasks was calculated to discern which swallowing task(s) yielded the worst performance.

RESULTS

Large-volume, thin-liquid swallowing tasks had the highest probabilities of yielding the OI scores for oral containment and airway protection. The cookie swallowing task was most likely to yield OI scores for oral clearance. Several swallowing tasks had nearly equal probabilities (≤ .20) of yielding the OI score.

CONCLUSIONS

The MBSS must represent impairment while requiring boluses that challenge the swallowing system. No single swallowing task had a sufficiently high probability to yield the identification of the worst score for each physiological component. Omission of swallowing tasks will likely fail to capture the most severe impairment for physiological components critical for safe and efficient swallowing. Results provide further support for standardized, well-tested protocols during MBSS.

Nutritional Aspects of Dysphagia Management

This chapter describes the nutritional aspects of dysphagia management by starting with the definition of these two conditions (dysphagia and malnutrition) that share three main clinical characteristics: (a) their prevalence is very high, (b) they can lead to severe complications, and (c) they are frequently underrecognized and neglected conditions. From an anatomical standpoint, dysphagia can result from oropharyngeal and/or esophageal causes; from a pathophysiological perspective, dysphagia can be caused by organic or structural diseases (either benign or malignant) or diseases causing impaired physiology (mainly motility and/or perception disorders). This chapter gathers up-to-date information on the screening and diagnosis of oropharyngeal dysphagia, the consequences of dysphagia (aspiration pneumonia, malnutrition, and dehydration), and on the nutritional management of dysphagic patients. Concerning this last topic, this chapter reviews the rheological aspects of swallowing and dysphagia (including shear and elongational flows) and its influence on the characteristics of the enteral nutrition for dysphagia management (solid/semisolid foods and thickened liquids; ready-to-use oral nutritional supplements and thickening powders), with special focus on the real characteristics of the bolus after mixing with human saliva.

A systematic review and meta-analysis of pneumonia associated with thin liquid vs. thickened liquid intake in patients who aspirate

OBJECTIVE

To investigate whether drinking thin liquids with safety strategies increases the risk for pneumonia as compared with thickened liquids in patients who have demonstrated aspiration of thin liquids.

DATA SOURCES

Seven electronic databases, one clinical register, and three conference archives were searched. No language or publication date restrictions were imposed. Reference lists were scanned and authors and experts in the field were contacted.

REVIEW METHODS

A blind review was performed by two reviewers for published or unpublished randomized controlled trials and prospective non-randomized trials comparing the incidence of pneumonia with intake of thin liquids plus safety strategies vs. thickened liquids in adult patients who aspirated on thin liquids. The data were extracted from included studies. Odds ratios (OR) for pneumonia were calculated from the extracted data. Risk of bias was also assessed with the included published trials.

RESULTS

Seven studies out of 2465 studies including 650 patients met the inclusion criteria. All of the seven studies excluded patients with more than one known risk factor for pneumonia. Six studies compared thin water protocols to thickened liquids for pneumonia prevention. A meta-analysis was done on the six studies, showing no significant difference for pneumonia risk (OR = 0.82; 95% CI = 0.05-13.42; p = 0.89).

CONCLUSIONS

There was no significant difference in the risk of pneumonia in aspirating patients who took thin liquids with safety strategies compared with those who took thickened liquids only. This result, however, is generalizable only for patients with low risk of pneumonia.

[Efficacy of early neurological and neurosurgical rehabilitation : Evidence-based treatment, outcome and prognostic factors]

BACKGROUND

Early neurological and neurosurgical rehabilitation (ENNR) as a complex post-acute form of treatment for patients with severe neurological diseases and continued need for intensive care is well established in Germany.

OBJECTIVE

To assess the efficacy of ENNR from the perspective of evidence-based medicine as well as to present data on the outcome of ENNR patients including the analysis of prognostic factors.

MATERIAL AND METHODS

A search was carried out in PubMed databases to identify early rehabilitation treatment forms evaluated by randomized controlled trials and with respect to large multicenter surveys of outcome and prognostic factors.

RESULTS

For ENNR as a complex treatment concept, effectiveness not has been shown with regard to evidence-based medicine but it includes individually effective treatment forms. In two large multicenter evaluations the average duration of treatment was between 51 and 57 days and mortality was between 6 % and 10 %, increasing with the proportion of mechanically ventilated patients. Lower need for nursing support on admission indicated better outcome, whereas mechanical ventilation was more likely to be associated with poor outcome. Long-term outcome was negatively influenced by mechanical ventilation as well as severe neurogenic dysphagia with and without the need for a tracheal cannula and/or percutaneous endoscopic gastrostomy (PEG) and also by severely impaired communication at the end of ENNR.

DISCUSSION

These prognostic factors indicate the primary aims of ENNR, which are to reduce the need for nursing support and to establish the capability for rehabilitation. If these aims are achieved, favorable functional and long-term outcome can be expected for ENNR patients. The presented studies verify the sustained efficacy of ENNR as an essential part of the overall treatment concept for severely neurologically impaired patients.

Texture Adaption in Dysphagia: Acceptability Differences Between Thickened and Naturally Thick Beverages

PURPOSE

The aim of the study was to investigate differences in the acceptability between thickened and naturally viscous beverages.

DESIGN

This was an exploratory, cross-sectional study.

METHODS

One hundred twenty-eight healthy volunteers rated overall liking/disliking of a selection of each of three thickened drinks and three beverages of natural viscosity pre- and postconsumption. Mean ratings were subjected to statistical analysis done with t tests.

FINDINGS

Although all naturally thick beverages evoked good expectations, there were significant differences in expected acceptance of thickened fluids concerning the kind of beverage. Postconsumption of naturally thick beverages were rated significantly better than thickened.

CONCLUSIONS

The findings suggest an alternative offer of naturally thick drinks and waiver of thickening water when viscosity adaption is needed.

CLINICAL RELEVANCE

The sufficient and safe oral fluid intake in dysphagia requires compliance to dietetic recommendations. Naturally thick beverages can contribute to increase the appeal of texture-modified diet.

Effect of Bolus Viscosity on the Safety and Efficacy of Swallowing and the Kinematics of the Swallow Response in Patients with Oropharyngeal Dysphagia: White Paper by the European Society for Swallowing Disorders (ESSD)

BACKGROUND

Fluid thickening is a well-established management strategy for oropharyngeal dysphagia (OD). However, the effects of thickening agents on the physiology of impaired swallow responses are not fully understood, and there is no agreement on the degree of bolus thickening.

AIM

To review the literature and to produce a white paper of the European Society for Swallowing Disorders (ESSD) describing the evidence in the literature on the effect that bolus modification has upon the physiology, efficacy and safety of swallowing in adults with OD.

METHODS

A systematic search was performed using the electronic Pubmed and Embase databases. Articles in English available up to July 2015 were considered. The inclusion criteria swallowing studies on adults over 18 years of age; healthy people or patients with oropharyngeal dysphagia; bolus modification; effects of bolus modification on swallow safety (penetration/aspiration) and efficacy; and/or physiology and original articles written in English. The exclusion criteria consisted of oesophageal dysphagia and conference abstracts or presentations. The quality of the selected papers and the level of research evidence were assessed by standard quality assessments.

RESULTS

At the end of the selection process, 33 articles were considered. The quality of all included studies was assessed using systematic, reproducible, and quantitative tools (Kmet and NHMRC) concluding that all the selected articles reached a valid level of evidence. The literature search gathered data from various sources, ranging from double-blind randomised control trials to systematic reviews focused on changes occurring in swallowing physiology caused by thickened fluids. Main results suggest that increasing bolus viscosity (a) results in increased safety of swallowing, (b) also results in increased amounts of oral and/or pharyngeal residue which may result in post-swallow airway invasion, (c) impacts the physiology with increased lingual pressure patterns, no major changes in impaired airway protection mechanisms, and controversial effects on oral and pharyngeal transit time, hyoid displacements, onset of UOS opening and bolus velocity-with several articles suggesting the therapeutic effect of thickeners is also due to intrinsic bolus properties, (d) reduces palatability of thickened fluids and (e) correlates with increased risk of dehydration and decreased quality of life although the severity of dysphagia may be an confounding factor.

CONCLUSIONS

The ESSD concludes that there is evidence for increasing viscosity to reduce the risk of airway invasion and that it is a valid management strategy for OD. However, new thickening agents should be developed to avoid the negative effects of increasing viscosity on residue, palatability, and treatment compliance. New randomised controlled trials should establish the optimal viscosity level for each phenotype of dysphagic patients and descriptors, terminology and viscosity measurements must be standardised. This white paper is the first step towards the development of a clinical guideline on bolus modification for patients with oropharyngeal dysphagia.

Oral perception of liquid volume changes with age

Bolus volume has been widely studied, and research has demonstrated a variety of physiological impacts on swallowing and swallowing disorders. Oral perception of bolus volume has not, to our knowledge, been investigated in association with normal ageing processes. Research suggests many sensory changes with age, some within the oral cavity, and changes in swallowing function with age have been defined. The role of perception in oropharyngeal deglutition with age requires further investigation. The purpose of this study was to establish the psychophysical relationship between liquid volume and oral perception and examine changes with age. Healthy young and older adults were prospectively assessed using a magnitude estimation task differentiating five volumes of water delivered randomly to the oral cavity. Results suggest a fourfold increase in liquid volume is required by older participants to perceive an approximate twofold increase in the perception of volume compared with younger healthy adults. Sensory receptors in the oral cavity provide a feedback loop that modulates the swallowing motor response so that it is optimal for the size and consistency of the bolus. Changes in perception of bolus volume with age are consistent with other perceptual changes and may provide valuable information regarding sensorineural rehabilitation strategies in the future.

Living with oropharyngeal dysphagia: effects of bolus modification on health-related quality of life--a systematic review

PURPOSE

Difficulty swallowing, oropharyngeal dysphagia, is widespread among many patient populations (such as stroke and cancer groups) and aged community-dwelling individuals. It is commonly managed with bolus modification: altering food (usually cutting, mashing or puréeing) or fluids (typically thickening) to make them easier or safer to swallow. Although this treatment is ubiquitous, anecdotal evidence suggests patients dislike this management, and this may affect compliance and well-being. This review aimed to examine the impact of bolus modification on health-related quality of life.

METHODS

A systematic review of the literature was conducted by speech pathologists with experience in oropharyngeal dysphagia. The literature search was completed with electronic databases, PubMed and Embase, and all available exclusion dates up to September 2012 were used. The search was limited to English-language publications which were full text and appeared in peer-reviewed journals.

RESULTS

Eight studies met the inclusion criteria. Generally, bolus modification was typically associated with worse quality of life. Modifications to foods appeared to be more detrimental than modifications to fluids, but this may be due to the increased severity of dysfunction that is implied by the necessity for significant alterations to foods. The number of studies retrieved was quite small. The diverse nature of methodologies, terminologies and assessment procedures found in the studies makes the results difficult to generalise.

CONCLUSION

Overall, even though the severity of dysphagia may have been a confounding factor, the impact of bolus modification on health-related quality of life in patients with oropharyngeal dysphagia appears to be negative, with increased modification of food and fluids often correlating to a decreased quality of life. Further, associated disease factors, such as decreased life expectancy, may also have affected health-related quality of life. More research is needed.

Five Days of Successful Oral Alimentation for Hospitalized Patients Based Upon Passing the Yale Swallow Protocol

Objective:

This study aimed to determine the success of oral alimentation and patient retention rate 1 to 5 days after passing the Yale Swallow Protocol.

Methods:

Participants were 200 consecutive acute care inpatients referred for swallow assessment. Inclusion criteria were adequate cognitive abilities to participate safely, completing an oral mechanism examination, and passing the 3-ounce water swallow challenge. Exclusion criteria were altered mental status, failing the 3-ounce challenge, preadmission dysphagia, head-of-bed restrictions < 30°, and a tracheotomy tube. Electronic medical record monitoring post-protocol passing for 1 to 5 consecutive days determined success of oral alimentation and retention rate.

Results:

All patients who remained medically and neurologically stable drank thin liquids and ate successfully 1 to 5 days after passing the protocol. Mean (SD) volume of liquid ingested per day was 474.2 (435.5) cc. Patient retention declined steadily from day of testing (n = 200) through post-testing day 5 (n = 95).

Conclusion:

Passing the Yale Swallow Protocol allowed for initial determination of aspiration risk followed by successful oral alimentation for 1 to 5 days in medically and neurologically stable acute care hospitalized patients and without the need for instrumental dysphagia testing. The decline in patient retention was expected because of increasingly rapid transit through the acute care setting, which often renders longer follow-up problematic.

Dysphagia: implications for older people

Dysphagia represents a salient concern in many conditions prevalent in older people. There are direct implications for morbidity and mortality. The importance of recognizing and managing dysphagia in hospital and the community also extends to psychosocial impact and quality of life, as well as health, economic and ethical-legal issues. This review outlines reasons for the importance of recognizing and treating dysphagia. It then proceeds to look at recent developments in our understanding of the nature, assessment and management of dysphagia in older people. Whilst there are well-established practices in assessment and management, ongoing work continues to challenge the validity and reliability of many methods. These concerns are covered and directions for future developments highlighted.

Validation of the Yale Swallow Protocol: a prospective double-blinded videofluoroscopic study

The purpose of this prospective, double-blinded, multirater, systematic replication study was to investigate agreement for aspiration risk, in the same individual, between videofluoroscopic swallow studies (VFSS) and the Yale Swallow Protocol. Participants were 25 consecutive adults referred for dysphagia testing who met the inclusion criteria of completion of a brief cognitive assessment, oral mechanism examination, and no tracheotomy tube. First, all participants were administered the Yale Swallow Protocol by two experienced speech-language pathologists trained in protocol administration. Failure criteria were inability to drink the entire amount, interrupted drinking, or coughing during or immediately after drinking. Second, all participants completed a VFSS within 5-10 min of protocol administration. A speech-language pathologist, blinded to protocol results, reviewed the VFSS to determine aspiration status in a binary (yes/no) manner. Inter-rater agreement between two speech-language pathologists was 100 % for identification of aspiration risk with the Yale Swallow Protocol. Inter-rater agreement between the speech-language pathologist and the radiologist for identification of aspiration status with VFSS was 100 %. Twenty percent of VFSS recordings were viewed again 3-6 months after initial data collection, and intrarater agreement for identification of thin liquid aspiration was 100 %. Sensitivity for the Yale Swallow Protocol = 100 %, specificity = 64 %, positive predictive value = 78 %, and negative predictive value = 100 %. Importantly, all participants who passed the protocol did not aspirate during VFSS. Multiple, double-blinded raters and VFSS as the reference standard agreed with previous research with a single, nonblinded rater and FEES as the reference standard for identification of aspiration risk. The clinical usefulness and validity of the Yale Swallow Protocol for determining aspiration risk in a small sample size of male participants has been confirmed. Future research is needed with a larger and more heterogeneous population sample.

Dysphagia and quality of life

Swallowing difficulties can be a symptom of many different disease processes, and are associated with adverse health outcomes; malnutrition, dehydration, pneumonia and death. The use of feeding tubes directly into the stomach as in percutaneous endoscopic gastrosomy (PEG) is an increasingly common treatment option for these patients with more and more being cared for in the community. Living with a gastrostomy tube brings physical and emotional impacts and direct consequences for quality of life. Guidance from the Royal College of Physicians recommends 'nil by mouth' should be a last resort even when swallow function is deemed unsafe. Impaired swallowing can cause increased anxiety and fear. Many patients avoid oral intake leading to malnutrition, isolation and depression. Understanding and balancing the risks and potential benefits of continuing oral intake or choosing gastrostomy makes this a complex and challenging area of health care.