Effects of bolus volume, viscosity, and repeated swallows in nonstroke subjects and stroke patients

Correlation between lesion location and dysphagia characteristics in post-stroke patients

OBJECTIVE

To assess the correlation between lesion location and swallowing function characteristics in post-stroke dysphagia (PSD) patients.

MATERIALS AND METHODS

We enrolled 133 PSD. The patients were divided into supratentorial and infratentorial stroke groups. We compared the measurements in the videofluoroscopic swallowing study (VFSS) with 3ml and 5 ml of diluted and thickened barium liquid data between supratentorial and brainstem stroke groups. We further compared the difference of VFSS measurements between patients with left hemispheric or right hemispheric lesions (further divided into unilateral hemispheric cortical and subcortical subgroups) and brianstem leison stroke group.To explore the lesion location's effect on different bolus volume, the VFSS measurements of 3ml and 5ml in each subgroups were compared respectively. The measurements of VFSS included the oral transit time, soft palate elevation duration, hyoid bone movement duration (HMD), UES opening duration, pharyngeal transit duration (PTD), stage of ansition duration, and laryngeal closure duration (LCD), the upper esophageal sphincter opening (UESO), hyoid bone superior horizontal displacement, and hyoid bone anterior horizontal displacement. General swallowing function was assessed using the Penetration Aspiration Scale (PAS) and Functional Oral Intake Scale (FOIS). We performed the paired t-test, Spearman's correlation, and Kruskal-Wallis test analysis to characterize the parameters among the groups.

RESULTS

Fifty-eight patients were assessed in the final analysis. The HMD (p = 0.019), PTD (p = 0.048) and LCD (p = 0.013) were significantly different between the supratentorial and brainstem lesion groups in 5ml volume. The HMD was significantly different (p = 0.045) between the left cortical and brainstem lesion groups. Significant differences in the HMD (p = 0.037) and LCD (p = 0.032) between the left subcortical and brainstem lesion groups were found in 5ml volume bolus. There was no group different when taking the 3ml volume bolus. Regarding the relationship between food bolus volume and swallowing functions, only the UESO demonstrated a significant difference in the subcortical lesion of the right hemisphere (p = 0.0032) compared the 3 ml and 5 ml volume bolus. The PTD demonstrated a moderate correlation with the PAS scores (r = 0.38, p = 0.0044). The HMD (r = 0.32, p = 0.018) and LCD (r = 0.29, p = 0.039) demonstrated weak correlations with the PAS scores. We did not identify any correlation between the VFSS parameters and FOIS scores in each subgroup level.

CONCLUSION

The PSD with brainstem lesion shows more sever dysfunction in the pharyngeal phases. The left hemisphere was engaged in both the oral and pharyngeal phases. Lesions in the bilateral cortical, subcortical, and brainstem regions may impair sensory input.

Quantifying Oropharyngeal Swallowing Impairment in Response to Bolus Viscosity

PURPOSE

The purpose of this study was to test the feasibility for quantifying changes in oropharyngeal swallowing impairment in response to alteration in bolus viscosity using a reliable and valid method of observational measurement-the Modified Barium Swallow Impairment Profile (MBSImP).

METHOD

This retrospective analysis included a heterogeneous cohort of 119 patients with suspected dysphagia that underwent a videofluoroscopic swallowing study as part of clinical care. Using consensus scoring, two expert clinicians assigned MBSImP scores to components related to oropharyngeal swallowing function between two bolus viscosities (thin liquid and pudding): epiglottic movement, laryngeal elevation, anterior hyoid excursion, tongue base retraction, pharyngeal stripping wave, and pharyngoesophageal segment opening (PESO). Comparisons between the two bolus viscosities were investigated for each component.

RESULTS

Higher (worse) scores were observed in the thin-liquid trial compared with the pudding trial for the following MBSImP components: anterior hyoid excursion (p = .03), epiglottic movement (p < .001), pharyngeal stripping wave (p < .001), and PESO (p = .002). Lower (better) scores were observed in the liquid trial compared with the pudding trial for one component-tongue base retraction (Component 15) only (p < .001).

CONCLUSION

These findings provide further evidence for positive influences of viscosity on the swallow mechanism, including influences of sensory feedback on the sensorimotor swallow program.

Observational study of effects of pharyngeal stimulation by carbonated solution on repetitive voluntary swallowing in humans

In this study, we conducted observational study to examine the effects of pharyngeal stimulation by a bolus of carbonated solution on repetitive voluntary swallowing in humans. Twelve healthy participants had a fine silicone tube inserted into their pharyngeal region, through which various solutions were slowly infused (0.2 mL/minute) to stimulate the pharyngeal mucosa without activating mechanoreceptors. The solutions included 0.3M NaCl (NaCl), carbonated 0.3M NaCl (NaCl + CA), 0.3M NaCl with acetic acid, distilled water, and carbonated distilled water. We used NaCl to inhibit water-sensitive neurons in the pharyngeal mucosa and enable the evaluation of the effects of carbonic acid stimulation on swallowing. Participants were instructed to repeat swallows as rapidly as possible during the infusion, and the swallowing interval (SI) was measured via submental surface electromyographic activity. SI was significantly shorter during the infusion of NaCl + CA, distilled water, and carbonated distilled water than during the infusion of NaCl. There was a significant positive correlation between SI with NaCl stimulation and the facilitative effects of the other solutions. Longer SIs with NaCl stimulation indicated potent facilitative effects. Thus, stimulation with NaCl + CA facilitated swallowing by reducing SI. Furthermore, the facilitative effects of SI were more pronounced in participants who had difficulty with repetitive voluntary swallowing. The sensation induced by carbonated solution may enhance the ability for repetitive voluntary swallowing, making it a potentially useful approach for rehabilitating patients with dysphagia.

Feel it or deal with it: Oral perception and aspiration risk in early stroke

BACKGROUND

Sensation and perception impairments are significant problems faced by individuals with early-stage stroke. Sensory inputs needed in swallowing guide the perceptual process with the involvement of cognitive functions. In the absence of sensory input, bolus perception may be altered, and swallowing safety may be compromised.

OBJECTIVES

This study aims to evaluate the oral perception of volume change and the aspiration risk of individuals with stroke and determine the relationship between oral perception and aspiration risk.

METHODS

Total participants were 35. The Gugging Swallowing Screening Test (GUSS) was used to determine individuals' risk of aspiration and divide them into groups 'aspiration risk' and 'non-aspiration risk'. The Oral Perception of Liquid Volume Changes Test (OPLVCT) was used to determine the level of oral perception.

RESULTS

The groups were statistically similar in terms of age and other descriptives. When the OPLVC test was examined, the scores of the aspiration risk group were significantly lower (p < .001). In addition, a moderate negative correlation was found between aspiration risk and the OPLVC scores (r: -0.502; p < .001).

CONCLUSION

In this study, a relationship was found between aspiration risk and oral perception. It also revealed that individuals with stroke who are at risk of aspiration have low oral perception abilities. Based on these results, it was concluded that these individuals cannot reliably determine the maximum volume of liquid to be consumed without assistance. We suggest that evaluations and training of oral perception should be added to the rehabilitation of individuals with stroke.

Thin Liquid Bolus Volume Alters Pharyngeal Swallowing: Kinematic Analysis Using 3D Dynamic CT

The previous studies reported that different volumes of thick liquid had an impact on spatiotemporal characteristics and pharyngeal response of swallowing. However, the bolus flow and swallowing motion pattern were different between thick and thin liquids. The effects of thin bolus volume on pharyngeal swallowing, especially true vocal cord (TVC) closure is still unclear. This study assessed the temporal characteristics when swallowing different volumes of thin liquid to determine the mechanical adaptation using 320-row area detector computed tomography (320-ADCT) and investigated a change of swallowing physiology including laryngeal closure, particularly TVC closure. Fourteen healthy women (28-45 years) underwent 320-ADCT while swallowing of 3, 10, and 20 ml of thin liquid barium in 45° semi-reclining position. Kinematic analysis was performed for each swallow including temporal characteristic, structural movements while swallowing, and maximal cross-sectional area of the upper esophageal sphincter (UES) opening. Bolus head reached to pharynx and esophagus earlier in larger volume significantly, indicating faster bolus transport as volume increased. There were significant effects on swallowing mechanism revealing earlier TVC closure and UES opening with increasing volume. Maximum cross-sectional area of the UES opening was increased to accommodate a larger bolus. Differences in mechanical adaptation through bolus transit and motion of swallowing structures were detected across increasing volumes. These volume-dependent adaptations potentially reduce the risk of aspiration. Understanding the swallowing physiological changes as volume increased is helpful for diagnosis and treatment of dysphagia patients as well as outcomes of swallowing rehabilitation in clinical practice.

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.

Detection of swallowing disorders with a multiple-channel surface electromyography sensor sheet

Background/purpose

A sensor sheet comprising multiple electromyography electrodes that can be used to measure a series of multiple muscle activities related to swallowing was recently developed. In this study, we aimed to evaluate its utility in detecting swallowing disorders with a new method for the identification of muscle activity.

Materials and methods

All participants were evaluated by using the repetitive saliva swallowing test and modified water swallowing test and were classified accordingly into participants with (n = 21; mean age, 81.6 [standard deviation, 10.1] years) and those without (n = 41; mean age, 70.0 [8.4] years) dysphagia. The sheet contains four pairs of electrodes, and surface electromyography (sEMG) was performed on the suprahyoid (position A: upper front of the suprahyoid muscles; position B: bottom rear of the suprahyoid muscles) and infrahyoid (position C: above the infrahyoid muscles; position D: beneath the infrahyoid muscles) muscles while the participants swallowed liquid, thickened water, paste, and jelly. The sEMG findings, including the duration of swallowing waveforms and the delay in swallowing onset from position A to positions B, C, and D, were compared between the groups.

Results

The duration of muscle activity differed between the groups in the infrahyoid muscles when jelly (Mann–Whitney U test; position C, P = 0.007 and position D, P = 0.018) and thickened water (position C, P = 0.033) were swallowed.

Conclusion

Our study demonstrates the utility of a novel sensor sheet developed for detecting swallowing disorders by using visual methods for identification of muscle activity.

Pharyngo-Esophageal Modulatory Swallow Responses to Bolus Volume and Viscosity Across Time

Objectives/Hypothesis

Modulation of the pharyngeal swallow to bolus volume and viscosity is important for safe swallowing and is commonly studied using high‐resolution pharyngeal manometry (HRPM). Use of unidirectional pressure sensor technology may, however, introduce variability in swallow measures and a fixed bolus administration protocol may induce time and order effects. We aimed to overcome these limitations and to investigate the effect of time by repeating randomized measurements using circumferential pressure sensor technology.

Study Design

Sub‐set analysis of data from the placebo arm of a randomized, repeated measures trial.

Methods

HRPM with impedance was recorded using a solid‐state catheter with 36 circumferential pressure sensors and 18 impedance segments straddling from hypopharynx to stomach. Testing included triplicates of 5, 10, and 20 ml thin liquid and 10 ml thick liquid boluses, the order of the thin liquid boluses was randomized. The swallow challenges were repeated approximately 10 minutes after finishing the baseline measurement.

Results

We included 19 healthy adults (10/9 male/female; age 24.5 ± 4.1 year). Intrabolus pressure, all upper esophageal sphincter (UES) opening and relaxation metrics, and flow timing metrics increased with larger volumes. A thicker viscosity decreased UES relaxation time, UES basal pressure, and flow timing metrics, whereas UES opening extent increased. Pre‐swallow UES basal pressure and post‐swallow UES contractile integral decreased over time.

Conclusion

Using circumferential pressure sensor technology, the effects of volume and viscosity were largely consistent with previous reports. UES contractile pressures reduced over time. The growing body of literature offers a benchmark for recognizing aberrant pharyngo‐esophageal motor responses.

Level of Evidence

3 Laryngoscope, 132:1817–1824, 2022

Advanced Machine Learning Tools to Monitor Biomarkers of Dysphagia: A Wearable Sensor Proof-of-Concept Study

Introduction

Difficulty swallowing (dysphagia) occurs frequently in patients with neurological disorders and can lead to aspiration, choking, and malnutrition. Dysphagia is typically diagnosed using costly, invasive imaging procedures or subjective, qualitative bedside examinations. Wearable sensors are a promising alternative to noninvasively and objectively measure physiological signals relevant to swallowing. An ongoing challenge with this approach is consolidating these complex signals into sensitive, clinically meaningful metrics of swallowing performance. To address this gap, we propose 2 novel, digital monitoring tools to evaluate swallows using wearable sensor data and machine learning.

Methods

Biometric swallowing and respiration signals from wearable, mechano-acoustic sensors were compared between patients with poststroke dysphagia and nondysphagic controls while swallowing foods and liquids of different consistencies, in accordance with the Mann Assessment of Swallowing Ability (MASA). Two machine learning approaches were developed to (1) classify the severity of impairment for each swallow, with model confidence ratings for transparent clinical decision support, and (2) compute a similarity measure of each swallow to nondysphagic performance. Task-specific models were trained using swallow kinematics and respiratory features from 505 swallows (321 from patients and 184 from controls).

Results

These models provide sensitive metrics to gauge impairment on a per-swallow basis. Both approaches demonstrate intrasubject swallow variability and patient-specific changes which were not captured by the MASA alone. Sensor measures encoding respiratory-swallow coordination were important features relating to dysphagia presence and severity. Puree swallows exhibited greater differences from controls than saliva swallows or liquid sips (p < 0.037).

Discussion

Developing interpretable tools is critical to optimize the clinical utility of novel, sensor-based measurement techniques. The proof-of-concept models proposed here provide concrete, communicable evidence to track dysphagia recovery over time. With refined training schemes and real-world validation, these tools can be deployed to automatically measure and monitor swallowing in the clinic and community for patients across the impairment spectrum.

Comparison of straw and cup for liquid swallowing in poststroke patients

The purposes of this study were to compare poststroke liquid swallowing methods by including a cup and a straw in videofluoroscopic swallowing studies (VFSS) and to test the hypothesis that increased aspiration would be observed with the cup compared to the straw. Eighty-five poststroke patients who had undergone VFSS using a spoon, cup, and straw were included. Penetration-aspiration scale and functional dysphagia scale (FDS) were used for assessment. These scores did not differ significantly between the cup and the straw. Higher FDS scores were found with the cup than with the straw in patients who had penetration/aspiration with both the cup and the straw and with the cup only. However, FDS scores did not differ significantly between the cup and the straw in patients who had penetration/aspiration with the straw only. Although advantages of the straw over the cup were clear, some patients showed penetration/aspiration only with the straw.

Clinical benefits of a swallowing intervention for esophageal cancer patients after esophagectomy

Dysphagia after esophagectomy is the main cause of a prolonged postoperative stay. The present study investigated the effects of a swallowing intervention led by a speech-language-hearing therapist (SLHT) on postoperative dysphagia. We enrolled 276 consecutive esophageal cancer patients who underwent esophagectomy and cervical esophagogastric anastomosis between July 2015 and December 2018; 109 received standard care (control group) and 167 were treated by a swallowing intervention (intervention group). In the intervention group, swallowing function screening and rehabilitation based on each patient's dysfunction were led by SLHT. The start of oral intake, length of oral intake rehabilitation, and length of the postoperative stay were compared in the two groups. The patient's subgroups in the 276 patients were examined to clarify the more effectiveness of the intervention. The start of oral intake was significantly earlier in the intervention group (POD: 11 vs. 8 days; P = 0.009). In the subgroup analysis, the length of the postoperative stay was also significantly shortened by the swallowing intervention in patients without complications (POD: 18 vs. 14 days; P = 0.001) and with recurrent laryngeal nerve paralysis (RLNP) (POD: 30 vs. 21.5 days; P = 0.003). A multivariate regression analysis identified the swallowing intervention as a significant independent factor for the earlier start of oral intake and a shorter postoperative stay in patients without complications and with RLNP. Our proposed swallowing intervention is beneficial for the earlier start of oral intake and discharge after esophagectomy, particularly in patients without complications and with RLNP. This program may contribute to enhanced recovery after surgery.

Thickened Liquids Using Pureed Foods for Children with Dysphagia: IDDSI and Rheology Measurements

Children with dysphagia, or swallowing disorder, are at an increased risk for developing respiratory compromise, failure to thrive, and aversion. Thickened liquids can be recommended for children with dysphagia, if shown to be effective on instrumental examination and if strategies/interventions with thin liquids are not successful. Thickened liquids have many benefits, including creating a more cohesive bolus, slowing oropharyngeal transit time, and reducing aspiration. However, preparing thickened liquids with commercially available thickeners can result in poor compliance due to concerns regarding taste, texture, accessibility, cost, thickness variability, and potential negative impact of these substances on a child's immature digestive tract. The purpose of this study was to determine if liquids could be successfully thickened with widely available, commercial pureed foods, and to assess how these mixtures compare to starch and gum based thickening agents. The International Dysphagia Diet Standardisation Initiative (IDDSI) flow test was performed for each sample of puree thickened liquids, gum based thickened water, and cornstarch based thickened water. In addition, rheology testing was performed on each category of the samples to measure viscosity at various shear rates and temperatures, and to assess the presence of yield stress. Results revealed that liquids thickened with smooth textured purees were comparable to commercial starch and gum based thickeners, and may be offered as a viable alternative.

Predicting penetration-aspiration through quantitative swallow measures of children: a videofluoroscopic study

PURPOSE

Quantitative measures have improved the reliability and accuracy in interpretation and reporting of videofluoroscopy (VFSS). Associations between quantitative VFSS measures and swallow safety in children are not widely reported. The ability to predict aspiration in children, even if not observed during brief VFSS, will improve diagnostic reporting and potentially reduce the need for extended radiation time. The aims of this study were to determine associations between quantitative fluoroscopic swallow measures and penetration-aspiration and to predict likelihood of penetration-aspiration.

METHODS

We selected videofluoroscopic data of 553 children from a pediatric hospital database for this single-center retrospective observational study. A standard protocol of VFSS administration was used and data were recorded at 30 frames-per-second. A set of quantitative and descriptive swallow measures was obtained using a specialized software with satisfactory inter-rater and intra-rater reliability. Binomial logistic regression with backward likelihood ratio was conducted, while controlling for age, gender, and etiology.

RESULTS

We found bolus clearance ratio (BCR), pharyngeal constriction ratio (PCR), duration to hyoid maximal elevation (Hdur), and total pharyngeal transit time (TPT) to be predictive of penetration-aspiration in children. PCR was the most predictive of penetration-aspiration in children (61.5%). Risk of aspiration was more than 100 times, when BCR =  ≥ 0.1, TPT =  ≥ 2 s, Hdur =  > 1 s or PCR =  ≥ 0.2 (p < 0.05 for all measures).

CONCLUSION

The results confirm the potential of objective quantitative swallow measures in predicting the risk of aspiration in children with dysphagia. These parameters provide predictive measures of aspiration risk that are clinically useful in identifying children of concern, even if no aspiration is observed during VFSS.

Dysphagia in Lateral Medullary Syndrome: A Narrative Review

Dysphagia is a common clinical feature of lateral medullary syndrome (LMS) and is clinically relevant because it is related to aspiration pneumonia, malnutrition, increased mortality, and prolonged hospital stay. Herein, the pathophysiology, prognosis, and treatment of dysphagia in LMS are reviewed. The pathophysiology, prognosis, and treatment of dysphagia in LMS are closely interconnected. Although the pathophysiology of dysphagia in LMS has not been fully elucidated, previous studies have suggested that the medullary central pattern generators coordinate the pharyngeal phases of swallowing. Investigation of the extensive neural connections of the medulla oblongata is important in understanding the pathophysiologic mechanism of dysphagia in LMS. Previous studies have reported that most patients with dysphagia in LMS have a relatively good prognosis. However, some patients require tube feeding for several months, even years, due to severe dysphagia, and little has been reported about conditions associated with a poor prognosis of dysphagia in LMS. Concerning specific therapeutic modalities for dysphagia in LMS, in addition to general modalities used for dysphagia treatment in stroke patients, non-invasive modalities, including repetitive transcranial magnetic stimulation and transcranial direct current stimulation, as well as invasive modalities, such as botulinum toxin injection, balloon catheter dilatation, and myotomy for relaxation of the cricopharyngeal muscle, have been applied. For the appropriate application of therapeutic modalities, clinicians should be aware of the recovery mechanisms and prognosis of dysphagia in LMS. Further studies on this topic, as well as studies involving large numbers of subjects on specific therapeutic modalities, should be encouraged.

Masticatory Adaptation to Occlusal Changes

This review deals with the frequent wide variability of masticatory capacity/incapacity. Neither researchers nor clinicians have taken sufficient account of this variability despite its implications for nutrition. Mastication in normal healthy oral conditions is first described, followed by a short presentation of the mechanisms of masticatory adaptation in the nervous system. Capacity, incapacity, and successful compensatory adaptation of mastication are then defined, along with the different methods used for their evaluation. Examples of adaptation needs are given, such as those concomitant with dental wear or occlusal changes. Finally, given its vital importance for deeply impaired mastication/deglutition function, the impact of masticatory adaptation processes on nutrition is examined.

Management of Dysphagia in Patients with Parkinson's Disease and Related Disorders

Various methods of rehabilitation for dysphagia have been suggested through the experience of treating stroke patients. Although most of these patients recover their swallowing function in a short period, dysphagia in Parkinson's disease (PD) and Parkinson-related disorder (PRD) degenerates with disease progression. Muscle rigidity and bradykinesia are recognized as causes of swallowing dysfunction, and it is difficult to easily apply the strategies for stroke to the rehabilitation of dysphagia in PD patients. Disease severity, weight loss, drooling, and dementia are important clinical predictors. Silent aspiration is a pathognomonic sign that may lead to aspiration pneumonia. Severe PD patients need routine video fluoroscopy or video endoscopy to adjust their food and liquid consistency. Patients with PRD experience rapid progression of swallowing dysfunction. Nutrition combined with nasogastric tube feeding or percutaneous endoscopic gastrostomy feeding should be considered owing to the increased risk of aspiration and difficulty administrating oral nutrition.

Variations in Healthy Swallowing Mechanics During Various Bolus Conditions Using Computational Analysis of Swallowing Mechanics (CASM)

Bolus properties such as volume, consistency, and density have been shown to influence swallowing through the analysis of kinematics and timing in both normal and disordered swallowing. However, inherent intra- and inter-person variability of swallowing cloud interpretation of group data. Computational analysis of swallow mechanics (CASM) is an established methodology that uses coordinate tracking to map structural movements during swallowing and yields statistically powerful analyses at both the group and individual levels. In this study, the CASM method was used to determine how different bolus properties (volume, consistency, and density) altered swallow mechanics in healthy young adults at the group and individual levels. Videofluoroscopic swallow studies of 10 (4 females) healthy young adults were analyzed using CASM. Five bolus types were administered in each study (3 × 5 ml 40% w/v nectar, 3 × 5 ml 22% w/v thin, 3 × 5 ml 40% w/v thin, 3 × 10 ml 22% w/v thin, and 3 × 20 ml 22% w/v thin). Canonical variate analyses demonstrated that bolus condition did not affect swallowing mechanics at the group level, but bolus condition did affect pharyngeal swallow mechanics at the individual level. Functional swallow adaptations (e.g., hyoid movement) to bolus conditions were not uniform across participants, consistent with the nonsignificant group finding. These results suggest that individual swallowing systems of healthy young individuals vary in how they respond to bolus different conditions, highlighting the intrinsic variability of the swallow mechanism and the importance of individually tailored evaluation and treatment of swallowing. Findings warrant further investigation with different bolus conditions and aging and disordered populations.

Reference Values for Healthy Swallowing Across the Range From Thin to Extremely Thick Liquids

Purpose Thickened liquids are frequently used as an intervention for dysphagia, but gaps persist in our understanding of variations in swallowing behavior based on incremental thickening of liquids. The goal of this study was to establish reference values for measures of bolus flow and swallowing physiology in healthy adults across the continuum from thin to extremely thick liquids. Method A sex-balanced sample of 38 healthy adults underwent videofluoroscopy and swallowed 20% weight-to-volume concentration barium prepared in thin and slightly, mildly, moderately, and extremely thick consistencies using a xanthan gum thickener. Participants took comfortable sips and swallowed without a cue; sip volume was measured based on presip and postsip cup weights. A standard operating procedure (the ASPEKT method: Analysis of Swallowing Physiology: Events, Kinematics and Timing) was used to analyze videofluoroscopy recordings. Results The results clarify that, for thin liquid sips (10-14 ml), a single swallow without clearing swallows is typical and is characterized by complete laryngeal vestibule closure, complete pharyngeal constriction, and minimal postswallow residue. Aspiration was not seen, and penetration was extremely rare. Bolus position at swallow onset was variable, extending as low as the pyriform sinuses in 37% of cases. With thicker liquids, no changes in event sequencing, laryngeal vestibule closure, pharyngeal constriction, or postswallow residue were seen. The odds of penetration were significantly reduced. A longer timing interval until onset of the hyoid burst movement was seen, with an associated higher bolus position at swallow onset. Other timing measures remained unaffected by changes in bolus consistency. Conclusion The results include new reference data for swallowing in healthy adults across the range from thin to extremely thick liquids.

Piecemeal Deglutition and the Implications for Pressure Impedance Dysphagia Assessment in Pediatrics

OBJECTIVES

High-resolution impedance manometry (HRIM) enables biomechanical swallow assessment. Piecemeal deglutition (PD) defines swallowing of a single bolus in 2 or more portions. We investigated PD sequences on HRIM recordings to ascertain appropriate swallow selection for analysis and to determine the impact of PD on swallow function measures.

METHODS

Pharyngo-esophageal motility and bolus flow were assessed in 27 children (19 M, mean age 15 months) with repaired esophageal atresia and trachea-esophageal fistula, but who were asymptomatic of oropharyngeal dysphagia. A consistent volume of between 2 and 5 mL saline boluses was given to each patient. Retrospectively, PD sequences were defined based on the number of swallows required to clear the bolus from the oral cavity: pattern A = 1-2 swallows; pattern B = 3 swallows; and pattern C = 4+ swallows. The largest bolus volume swallowed was noted as the dominant swallow in each pattern. Pressure Flow Analysis defined contractility, distension and flow timing metrics. Data were averaged for each PD pattern, and compared with dominant swallows from each pattern.

RESULTS

PD pattern B (43.7%) was the most prevalent across the cohort. PD patterns were similarly distributed across age groups (G1: <1 years, G2: 1-4 years). Differences in upper esophageal sphincter distension and pharyngeal flow timing measures were, however, seen in relation to both age and PD pattern, whereby a larger pharynx in older children elicited greater distension for a longer latency, and for larger volumes.

CONCLUSIONS

PD reduces bolus volume, and biomechanical swallow measures are impacted. PD is a necessary consideration for accurate HRIM analysis of swallow function. Selection of dominant swallows from a PD sequence provides a swallow profile which best represents a child's swallow function, and should always be reported and interpreted in context of the PD sequence observed.

Reduced pharyngeal constriction is associated with impaired swallowing efficiency in Amyotrophic Lateral Sclerosis (ALS)

BACKGROUND

Swallowing inefficiency is a prevalent but understudied problem in individuals with Amyotrophic Lateral Sclerosis (ALS). Although reduced pharyngeal constriction has been identified as a mechanism contributing to swallowing inefficiency following stroke, this relationship has not been empirically tested in the ALS population. This study sought to characterize profiles of swallowing efficiency in a sample of ALS patients and investigate relationships between pharyngeal constriction and swallowing efficiency.

METHODS

Twenty-six adults with ALS underwent videofluoroscopic swallowing studies, involving 3 mL-thin, 20 mL-thin, and 3 mL-pudding boluses. Full-length recordings were segmented into bolus clips and randomized for analysis. We recorded the total number of swallows per bolus and obtained normalized pixel-based measures of pharyngeal constriction area and post-swallow residue in the vallecular and pyriform sinuses. Linear mixed models with Spearman's correlations were used to determine relationships between pharyngeal constriction and swallowing efficiency, with added factors of bolus volume and thickness.

KEY RESULTS

Individuals with ALS demonstrated reduced pharyngeal constriction and increased vallecular and pyriform sinus residue, compared to norms. Reduced pharyngeal constriction had a significant effect on the presence of vallecular and pyriform sinus residue as well as the number of swallows per bolus. Increased bolus thickness was associated with increased vallecular residue, while increased bolus volume was associated with reduced pharyngeal constriction. Results were significant at P < 0.05.

CONCLUSIONS & INFERENCES

Our results suggest that reduced pharyngeal constriction is a significant physiological parameter related to swallow inefficiency in ALS. Future work is needed to corroborate these preliminary results and investigate factors to mitigate such impairments.

Swallowing outcomes in patients with subcortical stroke associated with lesions of the caudate nucleus and insula

Objective The present study was performed to investigate the relationships between swallowing outcomes and lesion location, bolus characteristics, and age in patients with subcortical stroke.

PATIENTS

Patients with subcortical and insular stroke (mean age, 57.38 ± 12.71 years) were investigated. All patients (n = 21) completed both brain magnetic resonance imaging studies and videofluoroscopic swallowing studies. Main Outcome Measures The oral transit duration, pharyngeal transit duration (PTD), laryngeal response duration, and Penetration-Aspiration Scale (PAS) score were applied to examine the efficiency of propulsion and airway protection in three swallowing tasks. Path analyses were performed to assess the relationships between swallowing outcomes and lesion location, age, bolus viscosity, and bolus volume. Results Caudate nucleus (CN) lesions were associated with higher PAS scores. Insular lesions were associated with a longer PTD. Advanced age was associated with a longer PTD. Bolus viscosity significantly moderated the association between CN lesions and higher PAS scores. Conclusions In the present cohort, CN lesions impacted airway protection and insular lesions impacted pharyngeal transit. An increased bolus viscosity reduced the aspiration severity. These results suggest that lesion location is an important indicator to predict subsequent dysphagia in patients with subcortical stroke.

The effect of bolus volume on laryngeal closure and UES opening in swallowing: Kinematic analysis using 320-row area detector CT study

This study investigated the effects of three different volumes of honey-thick liquid on the temporal characteristics of swallowing. Twenty-six healthy subjects (15 males, 11 females) underwent 320-row area detector CT scan while swallowing 3, 10 and 20 mL of honey-thick liquid barium. Three-dimensional images were created at 10 images/s. Kinematic events involving six structures (velopharynx, hyoid bone, epiglottis, laryngeal vestibule (LV), true vocal cords (TVC), upper esophageal sphincter (UES)) and timing of bolus movement were timed using frame by frame analysis. The overall sequence of events did not differ across three volumes; however, increasing bolus volume significantly changed the onset and termination of events. The bolus head reached to pharynx and esophagus earlier and the duration of bolus passing through UES was significantly longer in 10 and 20 mL compared to 3 mL (P < .05). Consequently, the onset of UES opening was significantly earlier with increased volume (P < .05). LV and TVC closure occurred later in 20 mL compared to 3 mL (P < .05). These changes in motion of pharynx and larynx appeared to promote swallow safety by preventing aspiration, suggesting that anatomical structure movements adapt in response to bolus volume. Our findings also suggest that the pharyngeal swallow behaviours may be modified by afferents in the oral cavity. The three-dimensional visualization and quantitative measurements provided by 320-ADCT provide essential benchmarks for understanding swallowing, both normal and abnormal.

Effects of age and viscosity on food transport and breathing-swallowing coordination during eating of two-phase food in nursing home residents

AIM

When eating food that contains both liquid and solid phases, the liquid component frequently enters the hypopharynx before swallowing and can increase the risk of aspiration. Thus, we examined whether the initial viscosity of mixed consistency food could alter pre-swallow food transport and breathing-swallowing coordination in older adults.

METHODS

Fiberoptic endoscopy was recorded while 18 healthy young adults and 19 older adults ate 5 g of steamed rice combined with 3 mL of blue-dye water. Liquid viscosity was set at three levels by the addition of a thickening agent (0 wt%, thin; 2 wt%, thicker; 4 wt%, higher-viscosity, respectively). We measured the timing of swallow initiation and its corresponding respiratory phase for each participant.

RESULTS

For thin mixed consistency food, whereas the timing of swallow initiation was comparable between young and older participants, swallowing was initiated during inspiration significantly more often in older participants (31.6 %) than in young participants (5.6 %). In contrast, the timing of swallow initiation was delayed in older participants for thicker and higher-viscosity foods, although swallowing was commonly initiated during expiration in both groups.

CONCLUSIONS

In older adults, we observed that swallow initiation function was preserved for thin mixed consistency samples, but breathing-swallowing coupling was diminished. For higher-viscosity foods, swallow initiation was delayed in this group, but breathing-swallowing coordination was not disturbed, probably as a result of the slow bolus flow into the hypopharynx. Thus, it appears the initial viscosity of mixed consistency food profoundly affects food transport before swallowing as well as breathing-swallowing coordination in nursing home residents. Geriatr Gerontol Int 2017; 17: 2171-2177.

Effect of posture on swallowing

BACKGROUND

Swallowing is a systematic process. Any structural, physiological or neurological disturbance in this process may cause dysphagia. Although there are studies that report head/neck movements during mastication, there are fewer studies that show the effect of different head/neck postures on difficulty while swallowing.

OBJECTIVES

To observe the effect of different body postures on the self-perceived difficulty while swallowing in normal healthy subjects.

METHODS

Participants were asked to swallow 25 ml of water in one go while sitting upright, sitting with head/neck flexed, head/neck extended and lying supine. Following this, they had to rate their self-perceived difficulty while swallowing on a scale of 0-10, 0 being most easy and 10 being most difficult.

RESULTS

186 subjects with mean age 32.7 SD 9.04 participated in this study. It was found to be least difficult to swallow when subjects were asked to swallow in upright sitting position. Statistically significant differences were found between sitting upright, sitting with head/neck flexed, head/neck extended and lying supine.

CONCLUSION

Postural modification may help in rehabilitation of patients with dysphagia by affecting bolus flow to improve speed and safety of swallowing by closure of airways to prevent aspiration.

Recommendation of Nasogastric Tube Removal in Acute Stroke Patients Based on Videofluoroscopic Swallow Study

Objective

To evaluate the safety of nasogastric tube (NGT) removal and change to oral feeding with a food thickener for acute stroke patients in whom a videofluoroscopic swallow study (VFSS) confirmed thin liquid aspiration.

Methods

We retrospectively examined data of 199 patients with first stroke who were diagnosed with dysphagia from 2011 to 2015. Swallowing function was evaluated using VFSS. Patients included in this study were monitored for 4 weeks to identify the occurrence of aspiration pneumonia. The penetration-aspiration scale (PAS) was used to assess VFSS findings. The patients were divided into thin-liquid aspiration group (group 1, n=104) and no thin-liquid aspiration group (group 2, n=95).

Results

The feeding method was changed from NGT feeding to oral feeding with food thickener (group 1) and without food thickener (group 2). The PAS scores of thin and thick liquids were 6.46±0.65 and 1.92±0.73, respectively, in group 1 and 2.65±0.74 and 1.53±0.58, respectively, in group 2. Aspiration pneumonia developed in 1.9% of group 1 and 3.2% of group 2 (p=0.578), with no significant difference between the groups.

Conclusion

We concluded that removing the NGT and changing to oral feeding with a food thickener is a safe food modification for acute stroke patients with thin liquid aspiration. Therefore, we recommend that VFSS should be conducted promptly in acute stroke patients to avoid unnecessary prolonged NGT feeding.

Increased Bolus Volume Effect on Delayed Pharyngeal Swallowing Response in Post-stroke Oropharyngeal Dysphagia: A Pilot Study

Objective

To confirm a relationship between the pharyngeal response and bolus volume, and examine whether increasing the fluid bolus volume can improve penetration and aspiration for stroke dysphagic patients.

Methods

Ten stroke patients with a delayed pharyngeal response problem confirmed by a videofluoroscopic swallowing study (VFSS) were enrolled. Each subject completed two swallows each of 2 mL, 5 mL, and 10 mL of barium liquid thinned with water. The pharyngeal delay time (PDT) and penetration-aspiration scale (PAS) were measured and the changes among the different volumes were analyzed.

Results

PDTs were shortened significantly when 5 mL and 10 mL of thin barium were swallowed compared to 2 mL. However, there was no significant difference in PAS as the bolus volume increased.

Conclusion

The increased fluid bolus volume reduced the pharyngeal delay time, but did not affect the penetration and aspiration status.

Influence of External Subglottic Air Flow on Dysphagic Tracheotomized Patients With Severe Brain Injury

OBJECTIVE

The aim of this study was to determine if external subglottic air flow (ESAF) influences swallowing frequency in severely dysphagic tracheotomized patients with brain injury.

METHODS

Ten patients were recruited at the neurological intensive care unit. The ESAF intervention was provided through the standard cuffed suction aid tracheotomy tube, which primarily is used to suction residual secretion volume from the subglottic area. Sessions were 150 minutes, and ESAF was provided at 60-65, 90-95, and 120-125 minutes at 3 L/min. Outcome measures included swallowing frequency (swallows/5 min) at 0-5 minutes (pre-baseline), 25-30 and 55-60 minutes (baseline/control), and 85-90, 115-120, and 145-150 minutes (postintervention). The residual secretion volume (ml) from the subglottic area was collected using a syringe at 0 minutes (pre-baseline), 30 and 60 minutes (baseline/ control), and at 90, 120, and 150 minutes (postintervention).

RESULTS

The mean (±SEM) swallowing frequency (swallows/5 min) increased from 0.60 ± 0.30 to 2.10 ± 0.70 during the ESAF intervention ( P < .001). The mean (±SEM) residual secretion volume reduced from 3.10 ± 0.31 ml to 0.50 ± 0.30 ml after the ESAF intervention ( P < .001).

CONCLUSION

The increase in swallowing frequency and reduction in residual secretion volume may indicate that ESAF influences swallowing parameters in patients with tracheotomy tubes.

Acoustic and Perceptual Profiles of Swallowing Sounds in Children: Normative Data for 4-36 Months from a Cross-Sectional Study Cohort

Limited data on cervical auscultation (CA) sounds during the transitional feeding period of 4-36 months in healthy children exist. This study examined the acoustic and perceptual parameters of swallowing sounds in children aged 4-36 months over a range of food and fluid consistencies. Using CA, swallowing sounds were recorded from a microphone as children ate or drank. Acoustic parameters of duration, peak frequency and peak intensity were determined. Perceptual parameters of swallowing/breath sounds heard pre-, during and post-swallow were rated ('present', 'absent', 'cannot be determined') for each texture. 74 children (35 males; mean age = 17.1 months [SD 10.0]) demonstrated mean swallow durations of <1 s. Increasing age correlated to reduced peak frequency on puree (r = -0.48, 95 % CI -0.66, -0.24). Age correlated to peak amplitude when swallowing puree (r = 0.27, 95 % CI 0.02, 0.49), chewable solids (r = 0.31, 95 % CI 0.02, 0.56) and thin fluids (r = 0.48, 95 % CI 0.27, 0.64). The bolus transit sound was present in all swallows. A majority of children had normal breathing sounds and coordinated swallows. A swallow duration of <1 s and the presence of a quick bolus transit sound with normal breathing sounds were found in healthy children. The normative data reported in this study provide a platform for future comparison to abnormal swallowing sounds in children.

Systematic review and meta-analysis of the diagnostic accuracy of the water swallow test for screening aspiration in stroke patients

AIM

The aim of this study was to determine the diagnostic accuracy of the water swallow test for screening aspirations in stroke patients.

BACKGROUND

The water swallow test is a simple bedside screening tool for aspiration among stroke patients in nursing practice, but results from different studies have not been combined before.

DESIGN

A systematic review and meta-analysis was conducted to provide a synthetic and critical appraisal of the included studies.

DATA SOURCES

Electronic literature in MEDLINE, EMBASE, CINAHL and other sources were searched systemically in this study. Databases and registers were searched from inception up to 30 April 2015.

REVIEW METHODS

This systematic review was conducted using the recommendations from Cochrane Collaboration for Systematic Reviews of Diagnostic Test Accuracy. Bivariate random-effects models were used to estimate the diagnostic accuracy across those studies. The tool named Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used to evaluate the quality of the studies.

RESULTS

There were 770 stroke patients in the 11 studies for the meta-analysis. The water swallow test had sensitivities between 64-79% and specificities between 61-81%. Meta-regression analysis indicated that increasing water volume resulted in higher sensitivity but lower specificity of the water swallow test.

CONCLUSIONS

This systematic review showed that the water swallow test was a useful screening tool for aspiration among stroke patients. The test accuracy was related to the water volume and a 3-oz water swallow test was recommended for aspiration screening in stroke patients.

Proposed Use of Thickener According to Fluid Intake on Videofluoroscopic Swallowing Studies: Preliminary Study in Normal Healthy Persons

OBJECTIVE

To examine the characteristics and changes in the pharyngeal phase of swallowing according to fluid viscosity in normal healthy persons, to help determine fluid intake methods in more detail than the use of standardized fluid.

METHODS

This was a prospective observational study involving 10 normal healthy adults. While the participants sequentially took in fluids with 10 different viscosities changes in the pharyngeal phase of the swallowing process were monitored using videofluoroscopic swallowing studies (VFSS). Twenty parameters of the pharyngeal phase, including epiglottis contact, laryngeal elevation, pharyngeal constriction, and upper esophageal sphincter opening, were determined and compared.

RESULTS

No significant viscosity-based changes in epiglottis contact, laryngeal elevation, or upper esophageal sphincter-opening duration of the pharyngeal phase were observed. However, pharyngeal transit time and time from the start of the pharyngeal phase to peak pharyngeal constriction were significantly delayed upon intake of fluid with viscosities of 150.0 centipoise (cP) and 200.0 cP.

CONCLUSION

VFSS analysis of fluid intake may require the use of fluids of various concentrations to determine a suitable viscosity of thickener mixture for each subject.

Biomechanics of human tongue movement during bolus compression and swallowing

We evaluated the effects of gel consistency and bolus volume on ingestion in humans. Eight healthy men were asked to ingest liquids, and sample foods of different gel consistencies and volumes, as usual. Tongue pressure against the hard palate was recorded at five points, and bolus flow was recorded using videoendoscopic images. The number of squeezes increased as gel consistency and volume increased. The integrated magnitude of tongue pressure during squeezing increased with increasing gel consistency. Bolus propulsion into the pharynx was affected by bolus characteristics, and location of the bolus head at the onset of pharyngeal swallowing was not related to squeezing behavior. The trigger point at which pharyngeal swallowing began was subject-dependent. During swallowing, the magnitude of tongue pressure moderately increased with increasing gel consistency, as compared with squeezing. Tongue pressure was not related to bolus volume. The current results suggest that patterns of tongue pressure during squeezing and swallowing are differentially affected by bolus conditions. However, healthy subjects differed in the techniques used for squeezing and swallowing.

Correlação entre tempo de trânsito oral e faríngeo no acidente vascular cerebral

Objetivo Correlacionar o tempo de trânsito oral total (TTOT) com o início da resposta faríngea (IRF) e o tempo de trânsito faríngeo (TTF) no indivíduo, após acidente vascular cerebral (AVC).Métodos O estudo incluiu 61 exames de videofluoroscopia de deglutição de indivíduos após AVC hemisférico isquêmico. Destes, 28 eram do gênero masculino e 33 do gênero feminino, com faixa etária variando de 40 a 101 anos (média de 65 anos). Para análise dos resultados, os indivíduos foram divididos em dois grupos. O Grupo 1 (G1) constou de 17 indivíduos com tempo de trânsito oral total até 2000 ms, conforme normalidade, e o Grupo 2 (G2), de 44 indivíduos com tempo de trânsito oral total maior que 2000 ms. Foi realizada análise quantitativa da deglutição orofaríngea. Cada indivíduo foi observado durante a deglutição de uma colher de 5 ml com alimento na consistência pastosa. Foi aplicado o teste de correlação de Spearman.Resultados Não houve correlação entre o G1 e a IRF e o TTF. Houve fraca correlação entre o G2 e os parâmetros estudados.Conclusão O aumento do tempo de trânsito oral total no indivíduo após AVC possui correlação fraca com o aumento do tempo na fase faríngea.

Patient-centred pharmaceutical design to improve acceptability of medicines: similarities and differences in paediatric and geriatric populations

Patient acceptability of a medicinal product is a key aspect in the development and prescribing of medicines. Children and older adults differ in many aspects from the other age subsets of population and require particular considerations in medication acceptability. This review highlights the similarities and differences in these two age groups in relation to factors affecting acceptability of medicines. New and conventional formulations of medicines are considered regarding their appropriateness for use in children and older people. Aspects of a formulation that impact acceptability in these patient groups are discussed, including, for example, taste/smell/viscosity of a liquid and size/shape of a tablet. A better understanding of the acceptability of existing formulations highlights opportunities for the development of new and more acceptable medicines and facilitates safe and effective prescribing for the young and older populations.

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.

Videofluoroscopic Validation of a Translational Murine Model of Presbyphagia

Presbyphagia affects approximately 40% of otherwise healthy people over 60 years of age. Hence, it is a condition of primary aging rather than a consequence of primary disease. This distinction warrants systematic investigations to understand the causal mechanisms of aging versus disease specifically on the structure and function of the swallowing mechanism. Toward this goal, we have been studying healthy aging C57BL/6 mice (also called B6), the most popular laboratory rodent for biomedical research. The goal of this study was to validate this strain as a model of presbyphagia for translational research purposes. We tested two age groups of B6 mice: young (4-7 months; n = 16) and old (18-21 months; n = 11). Mice underwent a freely behaving videofluoroscopic swallow study (VFSS) protocol developed in our lab. VFSS videos (recorded at 30 frames per second) were analyzed frame-by-frame to quantify 15 swallow metrics. Six of the 15 swallow metrics were significantly different between young and old mice. Compared to young mice, old mice had significantly longer pharyngeal and esophageal transit times (p = 0.038 and p = 0.022, respectively), swallowed larger boluses (p = 0.032), and had a significantly higher percentage of ineffective primary esophageal swallows (p = 0.0405). In addition, lick rate was significantly slower for old mice, measured using tongue cycle rate (p = 0.0034) and jaw cycle rate (p = 0.0020). This study provides novel evidence that otherwise healthy aging B6 mice indeed develop age-related changes in swallow function resembling presbyphagia in humans. Specifically, aging B6 mice have a generally slow swallow that spans all stages of swallowing: oral, pharyngeal, and esophageal. The next step is to build upon this foundational work by exploring the responsible mechanisms of presbyphagia in B6 mice.

Swallowing rehabilitation of dysphagic tracheostomized patients under mechanical ventilation in intensive care units: a feasibility study

Objective

The aim of the present study was to assess the feasibility of the early implementation of a swallowing rehabilitation program in tracheostomized patients under mechanical ventilation with dysphagia.

Methods

This prospective study was conducted in the intensive care units of a university hospital. We included hemodynamically stable patients under mechanical ventilation for at least 48 hours following 48 hours of tracheostomy and with an appropriate level of consciousness. The exclusion criteria were previous surgery in the oral cavity, pharynx, larynx and/or esophagus, the presence of degenerative diseases or a past history of oropharyngeal dysphagia. All patients were submitted to a swallowing rehabilitation program. An oropharyngeal structural score, a swallowing functional score and an otorhinolaryngological structural and functional score were determined before and after swallowing therapy.

Results

We included 14 patients. The mean duration of the rehabilitation program was 12.4 ± 9.4 days, with 5.0 ± 5.2 days under mechanical ventilation. Eleven patients could receive oral feeding while still in the intensive care unit after 4 (2 - 13) days of therapy. All scores significantly improved after therapy.

Conclusion

In this small group of patients, we demonstrated that the early implementation of a swallowing rehabilitation program is feasible even in patients under mechanical ventilation.

Swallowing, Nutrition, and Hydration During Acute Stroke Care

Dysphagia occurs in up to half of patients after an acute stroke and may cause dehydration, undernutrition, and aspiration pneumonia. Current evidence suggests that a systematic program of diagnosis and treatment of dysphagia in an acute stroke management plan may yield dramatic reductions in aspiration pneumonia rates. There is also some evidence that nutritional supplementation and proper hydration may reduce morbidity and mortality in acute stroke patients. This article focuses on the recent advances in the evaluation and management of dysphagia, undernutrition, and dehydration related to acute stroke. A summary of pertinent studies in the area of stroke dysphagia and nutrition is also included.

Effect of bolus volume and consistency on swallowing events duration in healthy subjects

Background/Aims

Swallowing is a complex function with the control of the swallowing center being located in the brain stem. Our aim in this investigation was to evaluate, in healthy volunteers, the oral and pharyngeal transit of 2 bolus volumes and 2 consistencies, and the influence of these boluses on the proportion of pharyngeal clearance duration/hyoid movement duration.

Methods

Videofluoroscopic evaluation of swallows was performed in 30 healthy volunteers, aged 29–77 years (mean 58 years). The subjects swallowed in duplicate of 5 mL and 10 mL of thick liquid barium and honey thick barium. We measured the duration of oral transit, pharyngeal transit, pharyngeal clearance, upper esophageal sphincter opening, hyoid movement, oropharyngeal transit, and the relation pharyngeal clearance duration/hyoid movement duration.

Results

A 10 mL bolus volume caused a longer UES opening duration than a 5 mL bolus volume, for both consistencies. The pharyngeal transit was longer for honey thick bolus consistency than for thick liquid, with both the volumes of 5 mL and 10 mL. For pharyngeal clearance, the difference was significant only with the 10 mL bolus volume. There was no difference associated with bolus volume or consistency in the relation between pharyngeal clearance duration and hyoid movement duration.

Conclusions

Increase in the swallowed bolus volume causes a longer UES opening duration and an increase in bolus consistency from thick liquid to honey thick causes a longer pharyngeal transit duration. The proportion between pharyngeal clearance and hyoid movement does not change with bolus volume or bolus consistency.