Different clinical predictors of aspiration pneumonia in dysphagic stroke patients related to stroke lesion: A STROBE-complaint retrospective study

Although stroke is one of the most common causes of dysphagia, no studies have investigated the radionuclide salivagram as a predictor of aspiration pneumonia in patients with stroke. In addition, few researches on the risk factors of aspiration pneumonia in patients with subacute and chronic stroke undergoing rehabilitation in the rehabilitation unit have been rarely conducted. In this study, therefore, we investigated whether a radionuclide salivagram could predict aspiration pneumonia, and tried to find other clinical factors that may be helpful in predicting aspiration pneumonia in stroke patients undergoing rehabilitation in the rehabilitation department.From March 2013 and January 2018, a retrospective review of the medical records of 1182 subacute and chronic stroke patients who were admitted to rehabilitation department (South Korea) was carried out. We included 117 stroke patients with swallowing difficulties who were admitted to our rehabilitation department and satisfied our criteria retrospectively. Stroke lesion, the degree of paralysis, sex, age, onset duration, feeding methods, the Mini-Mental State Examination (MMSE), the Global Deterioration Scale (GDS), the presence of aspiration in VFSS or salivagram, the penetration-aspiration scale (PAS), and the total score of the Modified Barthel Index (MBI) were investigated by reviewing medical records.To evaluate the predictor of aspiration pneumonia for patients with stroke, multivariate logistic regression analysis with forward stepwise was performed. In the results of this study, only MMSE was significant as a clinical predictor, but not aspiration in VFSS or salivagram in multivariate analysis of supratentorial stroke patients (OR, 0.895) (95% CI, 0.830-964). In multivariate analysis of infratentorial stroke patients, combined results of salivagram and VFSS (aspiration in a salivagram or VFSS) (OR, 0.956) (95% CI, 0.919-995), and total MBI scores were significant as clinical predictors (OR, 24.882) (95% CI, 1.298-477.143).In conclusion, MMSE can be a clinical predictor of the occurrence of aspiration pneumonia in patients with supratentorial stroke. In contrast, total MBI score and combined results of a salivagram and VFSS can be clinical predictors of the occurrence of aspiration pneumonia in patients with infratentorial stroke.

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.

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.

Hard to swallow: Developmental biological insights into pediatric dysphagia

Pediatric dysphagia-feeding and swallowing difficulties that begin at birth, last throughout childhood, and continue into maturity--is one of the most common, least understood complications in children with developmental disorders. We argue that a major cause of pediatric dysphagia is altered hindbrain patterning during pre-natal development. Such changes can compromise craniofacial structures including oropharyngeal muscles and skeletal elements as well as motor and sensory circuits necessary for normal feeding and swallowing. Animal models of developmental disorders that include pediatric dysphagia in their phenotypic spectrum can provide mechanistic insight into pathogenesis of feeding and swallowing difficulties. A fairly common human genetic developmental disorder, DiGeorge/22q11.2 Deletion Syndrome (22q11DS) includes a substantial incidence of pediatric dysphagia in its phenotypic spectrum. Infant mice carrying a parallel deletion to 22q11DS patients have feeding and swallowing difficulties that approximate those seen in pediatric dysphagia. Altered hindbrain patterning, craniofacial malformations, and changes in cranial nerve growth prefigure these difficulties. Thus, in addition to craniofacial and pharyngeal anomalies that arise independently of altered neural development, pediatric dysphagia may result from disrupted hindbrain patterning and its impact on peripheral and central neural circuit development critical for feeding and swallowing. The mechanisms that disrupt hindbrain patterning and circuitry may provide a foundation to develop novel therapeutic approaches for improved clinical management of pediatric dysphagia.

The Effect of Oral Processing on the Viscosity of Thickened Drinks for Patients With Dysphagia

Objective

To determine whether a gum-containing thickener maintains its viscosity better during oral processing than a completely starch-based thickener.

Methods

Thirty-five healthy volunteers participated in a double-blind, cross-over study. Artificial tap water was thickened to honey-like consistency (effective viscosity of 1,300±100 mPa·s at a shear rate of 50 per second at 20℃) with a starch-based thickener (SB) or a gum-containing thickener (GC). Bolus viscosity was determined after standardized oral processing of the thickened water by the subjects for 10 and 20 seconds. Significant effects were determined by ANOVA analysis and pairwise comparisons.

Results

Both thickeners were susceptible to breakdown during oral processing. However, GC-thickened water retained its viscosity significantly better than SB-thickened water.

Conclusion

The presence of gums has a protective effect on the starch hydrolysis by salivary amylase in thickened drinks, which may facilitate safer swallowing.

Findings of Abnormal Videofluoroscopic Swallowing Study Identified by High-Resolution Manometry Parameters

OBJECTIVE

To identify the parameters of high-resolution manometry (HRM) with a significant correlation to abnormal findings of videofluoroscopic swallowing study (VFSS).

DESIGN

Prospective study.

SETTING

Hospital rehabilitation department.

PARTICIPANTS

Patients with dysphagia symptoms (N=40).

INTERVENTION

Participants were evaluated once using VFSS in neutral head position and evaluated twice using HRM with 5mL of thin fluid.

MAIN OUTCOME MEASURES

HRM parameters included maximal pressure, area integral, rise time, duration of the velopharynx and tongue base, maximal pressure of pre-upper esophageal sphincter (UES), low pharynx, cricopharyngeus, minimal UES pressure, UES activity time, and nadir UES duration. HRM parameters were compared with the findings of VFSS. Receiver operating characteristic analysis was performed to obtain the cutoff value, sensitivity, and specificity of HRM parameters for the prediction of findings of VFSS.

RESULTS

The maximum pressure of the velopharynx showed a significantly positive prediction for most abnormal parameters of VFSS in the pharyngeal phase. Nadir UES pressure duration was significant for impaired laryngeal elevation, residue at pyriformis sinus, and combination of penetration and aspiration. The maximum pressure of the velopharynx <180.0 showed 100% sensitivity and 75% specificity for the presence of penetration and aspiration, and the cutoff point of 178.8 showed 86.7% sensitivity and 75% specificity for the presence of subglottic aspiration.

CONCLUSIONS

This study identified significant HRM parameters that are highly specific for individual abnormalities of VFSS, suggesting the cutoff value, sensitivity, and specificity. Because HRM could inform the quantitative measurement of pharyngeal weakness, the cutoff value for HRM parameters could be used to predict aspiration in patients with pharyngeal weakness.

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

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

Matching the rheological properties of videofluoroscopic contrast agents and thickened liquid prescriptions

In the treatment of oropharyngeal dysphagia, the link between diagnosis and prescription of thickened liquids that are safe to swallow is not always straightforward. Frequently, the capacity to objectively assess and quantify the rheological properties of diagnostic test fluids and to select "rheologically equivalent" dietary products is missing. Perhaps sometimes the importance of an objective comparison is not fully appreciated because two liquids seem reasonably similar in a subjective comparison (e.g., flow from a spoon). The present study deals with some of these issues. Shear viscosity measurements were used to characterize the flow behavior of videofluoroscopic contrast agents and of thickened fluids prepared with commercial thickening agents. Effects of time and composition of the different fluids were analyzed regarding shear-rate-dependent viscosity. Nearly all materials tested showed a pronounced dependence of viscosity with shear rate ("shear thinning"). Results confirm that it is feasible (but not always straightforward) to "match" the viscosities of diagnostic fluids and thickened beverages if certain precautions are taken. For example, the time required to reach final viscosity levels can be significant for some thickeners, particularly when used with liquids containing contrast agents. It is recommend to use only diagnostic materials and thickening agents for which reliable viscosity data are available.

Comparison between the radionuclide salivagram and videofluoroscopic swallowing study methods for evaluating patients with aspiration pneumonia

OBJECTIVE

A videofluoroscopic swallowing study (VFSS) is generally used to assess dysphagia and aspiration, although false-negative results may be obtained. Saliva aspiration may cause false-negative VFSS findings in elderly people. A radionuclide salivagram can be useful in detecting saliva aspiration. We therefore compared these two methods for the evaluation of patients with aspiration pneumonia.

METHODS

We prospectively enrolled 50 patients with aspiration pneumonia into this study. All patients underwent VFSS, and were evaluated on the Penetration-Aspiration Scale. A salivagram was performed on the day after VFSS and each patient received 1 mL Tc-99 m DTPA sublingually. Both dynamic and delayed images were obtained.

RESULTS

Aspiration was observed in 34% of patients by salivagram and in 42% by VFSS. The frequency of tests that were positive for aspiration pneumonia using a combination of the two methods was 52%. Five patients with positive aspiration findings on salivagram were negative on VFSS. The association between VFSS and salivagram findings was significant but the total agreement was 72%. The frequency of aspiration pneumonia was significantly associated with an abnormal salivagram finding.

CONCLUSIONS

A salivagram may be a useful method for the evaluation of aspiration in elderly people, and a combination of the VFSS and salivagram methods could enable a more effective investigation of aspiration pneumonia.

Changes of timing variables in swallowing of boluses with different viscosities in patients with dysphagia

OBJECTIVES

To evaluate the timing of the swallowing process and the effect of bolus viscosity on swallowing.

DESIGN

Prospective observational study.

SETTING

General teaching hospital, rehabilitation unit.

PARTICIPANTS

We enrolled patients with dysphagia (n=82) in a videofluoroscopic swallowing study (VFSS) from January 13, 2009, to October 22, 2009. Based on VFSS results, we classified patients as "thin-fluid aspirators" (n=40) or as "nonaspirators" (n=42).

INTERVENTIONS

Swallowing of a 5-mL thick bolus and a 5-mL thin bolus in all patients.

MAIN OUTCOME MEASURES

Kinematic analysis of various variables during the swallowing process (pharyngeal phase), including epiglottis contact with the bolus, laryngeal elevation, pharyngeal constriction, and upper esophageal sphincter opening.

RESULTS

In both groups, the thin bolus arrived at the vallecular pouch earlier than the thick bolus. During swallowing of the thick bolus, the thin-fluid aspirators had a delayed latency of upper esophageal sphincter opening, delayed laryngeal elevation to peak level, and significantly longer rise time of laryngeal elevation.

CONCLUSIONS

Our results indicate clear differences in the degree of adaptation to bolus viscosity between patients classified as thin-fluid aspirators and as nonaspirators. These differences were mainly in activities of laryngeal elevators rather than pharyngeal constrictors.

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

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

Evaluation of dysphagia after cervical surgery using laryngeal electromyography

The purpose of this study was to investigate the causes of dysphagia after cervical surgery using laryngeal electromyography (LEMG), and the effect of laryngeal neuropathy on the severity of dysphagia. Seventeen patients with dysphagia evident after cervical surgery were included. Video fluoroscopic swallow study (VFSS) parameters evaluated included the volume of residue in the vallecular pouch and the pyriform sinus, the Rosenbek penetration-aspiration scale (PAS), and the swallowing function scoring system (SFSS). By VFSS findings, patients were classified into a mild or severe dysphagia group. Nine of 17 patients showed voice change. SFSS scores were 0 in 2 patients, 3 in 1 patient, 4 in 1 patient, 5 in 1 patient, and 6 in 12 patients. PAS scores were 1 in 8 patients, 2 in 5 patients, 7 in 3 patients, and 8 in 1 patient. Laryngeal neuropathy was evident in seven patients (41.2%). Of these, all patients exhibited recurrent laryngeal neuropathy and 28.6% had superior laryngeal neuropathy. When we evaluated LEMG findings with respect to the severity of dysphagia, the severe dysphagia group showed significant association with the presence of laryngeal neuropathy (p = 0.006). Although the level of residue in the vallecular pouch was not associated with the presence of laryngeal neuropathy (p = 0.442), the amount of residue in the pyriform sinus did show a significant association (p = 0.020).

Nutrition management for the patient requiring prolonged mechanical ventilation

Patients requiring prolonged mechanical ventilation are often medically complex and present with a wide range of pulmonary conditions, including neuromuscular diseases, chronic pulmonary diseases, and chronic critical illness. These patients present the nutrition support professional with many challenges. However, accurate nutrition assessment, timely and effective nutrition interventions, and careful monitoring will help patients meet their medical and nutrition goals.

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

Infants experiencing dysphagia may undergo a videofluoroscopic swallow study (VFSS) to assess radiologically their coordination for sucking, swallowing, and breathing. No studies known to these authors have investigated whether the liquids used during infant radiological procedures are representative of liquids routinely fed to infants (e.g., formula). This study used an Advanced Rheometric Expansion System (ARES) strain-controlled rheometer to compare prethickened antiregurgitation formula, regular (thin) infant formula, and two types of regular infant formula, hand-thickened with a thickening agent and with liquid Polibar™ (barium-impregnated liquid). The viscosity, density, and yield stress of all samples were determined. Heated versus cooled liquids were compared. Results showed a significant difference in all rheological and material property parameters among the barium-impregnated liquids and the thickened and unthickened infant formula. This finding has important implications for the interpretation of the radiological results and subsequent clinical recommendations.