Linking the impact of aspiration to host variables using the BOLUS framework: support from a rapid review.

Purpose: The purpose of this rapid review was to identify the level of evidence for a previously proposed theoretical framework to assess risks associated with prandial aspiration using the host as a central theme. Methods: Covidence software was used to search two databases (PubMed and Web of Science). PEDro scale was utilized to determine the quality of individual studies. Data points were evaluated for level of support and determined to be either conclusive, suggestive, unclear, or not supportive. Within each component of the framework, data points were clustered to determine the level of evidence as strong, moderate, insufficient, or negative. Results: The rapid review process resulted in a limited number of publications investigating host variables impact on outcomes for patients with swallowing disorders. Overall, it yielded 937 articles, of which, upon review, 16 articles were selected for data extraction. There was a strong level of evidence to support that (a) as viscosity and density of aspirate increased, so did the likelihood of general medical complications, (b) poor oral care and oral health increase the risk of a pulmonary or general medical complication, and (c) the presence of oropharyngeal or laryngeal tubes increases the risk of a pulmonary consequence. There was moderate evidence to support the impact of amount and frequency of aspiration on outcomes. There was insufficient evidence to determine relationships for all other aspects of the BOLUS framework. Conclusion: Additional evidence to support the BOLUS framework was obtained; however, the number of studies was limited. A more thorough review such as a systematic review should be employed.

The Impact of Videofluoroscopic Pulse Rate on Duration and Kinematic Measures in Infants and Adults with Feeding and Swallowing Disorders.

This investigation assessed the impact of temporal resolution during a videofluoroscopic evaluation of swallowing (VFSS) on measures of duration and kinematics. Thirty adult and ten infant swallow studies, all acquired at 30 frames and 30 pulses per second, were obtained from a New Mexico hospital. All swallow studies were altered to simulate 15 and 5 pulses per second. Duration measures included pharyngeal response time, duration of upper esophageal sphincter (UES) opening, velopharyngeal closure duration and total swallow duration. Kinematic measures were assessed in adults only and included peak hyoid position and extent of UES opening during the swallow. Analysis of outcome measures was performed and compared across the three temporal resolutions (30, 15, and 5 pulses per second). For data points where normative values are available, we evaluated the impact of temporal resolution on clinical determination (i.e., did a change in pulse rate alter the clinical classification). Kinematic and duration measures were altered with changes in pulse rate and these changes increased as temporal resolution decreased. For outcome measures where normative values are available, accuracy of clinical determination decreased with decreased pulse rate. Temporal resolution impacts duration and kinematic measures. However, the direction of these changes is unpredictable, indicating sensitivity and specificity are both affected. Without a predictable impact, the use of lower pulse rates may alter clinical impressions and treatment recommendations yielding inappropriate treatment goals and treatment duration.

The Development and Implementation of A Data Repository for Swallow Studies.

PURPOSE: The purpose of this clinical note is to (a) describe the development of an open-source data repository of videofluoroscopic evaluations of swallow studies (VFSS) from individuals across the lifespan with various feeding and swallowing disorders, and (b) to qualitatively assess the usefulness of a repository to engage students in research in swallowing disorders. METHOD: This project was divided into two phases. Phase 1 focused on the development of the repository. This entailed identifying videos, removing private information, developing codes for swallow events and bolus variables, transcribing videos, and uploading them to a publicly available site for easy access. Phase 2 assessed the usefulness of the repository as a research tool. In this phase, a group of graduate and undergraduate students investigated a research question of interest to them. Each phase incorporated a qualitative analysis to examine the challenges encountered in that given phase. RESULTS: An open-source data repository of swallow studies, called DysphagiaBank, was successfully developed and uploaded into the TalkBank data repository. The database was easily employed by both graduate and undergraduates to engage in research in a timely fashion. Across qualitative analysis, the single consistent barrier to success was the COVID-19 pandemic that impacted access to campus and adequate internet for streaming. CONCLUSION: The use of an open-source data repository improved our students abilities to engage in research and enhanced their understanding of swallow physiology across the lifespan.

Risk of an Adverse Event in Individuals Who Aspirate: A Review of Current Literature on Host Defenses and Individual Differences.

PURPOSE: The presence of oropharyngeal dysphagia increases the likelihood of prandial aspiration, and aspiration increases the likelihood of a dysphagia-related pulmonary sequelae such as aspiration pneumonia, acute respiratory distress syndrome, pulmonary fibrosis, and even death. Although these outcomes are unfortunate, it is important to point out that these consequences are not solely determined by the presence of aspiration. The purpose of this tutorial is to provide current information on pulmonary defenses and the variables that increase risk of an adverse outcome in individuals who aspirate. METHOD: This tutorial reviews the basics of lung defenses and summarizes the literature to make the case that the host is a central theme in dysphagia management. Case studies are employed to highlight the key variables. RESULTS: Based on a literature review, a series of questions are proposed for consideration in dysphagia management. These questions, which take the focus away from the presence of aspiration and toward the associated risks within an individual, are then applied to two case studies. CONCLUSIONS: A guiding framework is proposed to encourage clinicians to assess more than the presence of aspiration and consider the individual's ability to cope with the aspirated material. In the presence of aspiration, clinicians are urged to focus on the risk factors that can lead to a negative consequence, identify which factors are modifiable, and determine when a level of risk is acceptable.

The Relationship Between Culture, Quality of Life, and Stigma in Hispanic New Mexicans With Dysphagia: A Preliminary Investigation Using Quantitative and Qualitative Analysis.

Purpose The purpose of this investigation was to (a) identify the relationship between level of acculturation, and quality of life (QOL) and stigma and (b) explore the QOL experiences for Hispanic New Mexicans with dysphagia. Method This study includes 7 New Mexicans who self-identified as Hispanic. This prospective investigation was completed in 2 phases. In the quantitative phase, all participants completed the (a) the SWAL-QOL ( McHorney et al., 2000 ), (b) the Neuro-QoL Stigma subtest ( Gershon et al., 2012 ), and (c) the Acculturation Rating Scale for Mexican Americans-II (ARSMA-II; Cuellar, Arnold, & Maldonado, 1995 ). In the qualitative phase, 3 participants were selected from the quantitative phase to complete the qualitative phase. These participants were selected to allow for distribution across levels of acculturation, and each of them participated in interviews designed to explore QOL experiences. Interviews were analyzed to identify themes. The occurrence of themes is discussed as a function of level of acculturation. Results There is no clear relationship between acculturation and QOL. A strong nonsignificant correlation was observed between acculturation and stigma. QOL experiences, as identified from the interviews, were classified into 2 broad categories: emotional experiences (stigma, distrust, fear, frustration, religion, and impact) and swallow safety (symptoms, treatment, triggers, and compensatory strategies). Conclusions Level of acculturation did not relate to measures of mental health or fatigue. Yet, both quantitative and qualitative analyses support a relationship between level of acculturation, and symptom reporting and religion, as well as patient perception of stigma.

Muscle weakness and speech in oculopharyngeal muscular dystrophy.

PURPOSE: We documented speech and voice characteristics associated with oculopharyngeal muscular dystrophy (OPMD). Although it is a rare disease, OPMD offers the opportunity to study the impact of myopathic weakness on speech production in the absence of neurologic deficits in a relatively homogeneous group of speakers. METHODS: Twelve individuals with OPMD and 12 healthy age-matched controls underwent comprehensive assessment of the speech mechanism including spirometry (respiratory support), nasometry (resonance balance), phonatory measures (pitch, loudness, and quality), articulatory measures (diadochokinetic rates, segment duration measures, spectral moments, and vowel space), tongue-to-palate strength measures during maximal isometric and speechlike tasks, quality-of-life questionnaire, and perceptual speech ratings by listeners. RESULTS: Individuals with OPMD had substantially reduced tongue strength compared to the controls. However, little impact on speech and voice measures or on speech intelligibility was observed except for slower diadochokinetic rates. CONCLUSIONS: Despite having less than half the maximal tongue strength of healthy controls, the individuals with OPMD exhibited minimal speech deficits. The threshold of weakness required for noticeable speech impairment may not have been reached by this group of adults with OPMD.

Is tongue strength an important influence on rate of articulation in diadochokinetic and reading tasks?

PURPOSE: The purpose of this study was to assess the relationship between tongue strength and rate of articulation in 2 speech tasks, diadochokinetic rates and reading aloud, in healthy men and women between 20 and 78 years of age. METHOD: Diadochokinetic rates were measured for the syllables /p/, /t/, /k/, and /ptk/, and articulation rates were calculated for a reading of the Rainbow Passage for 57 adult volunteers. The Iowa Oral Performance Instrument (LLC Northwest) was used to obtain maximum tongue pressure, tongue pressure exerted during production of /t/, and tongue endurance. Correlation analyses were performed to determine the relation among articulation rate and tongue pressure and endurance measures. RESULTS: Maximum tongue pressure, the pressure used to produce /t/, the proportion of maximum pressure used to produce /t/, and tongue endurance were poor predictors of diadochokinetic rates and articulation rate in reading for healthy speakers. Discussion Focus must remain on factors beyond strength, such as movement precision and coordination, to improve researchers' understanding of normal and disordered speech production in adults.

Swallow characteristics in patients with oculopharyngeal muscular dystrophy.

PURPOSE: This prospective investigation evaluates oral weakness and its impact on swallow function, weight, and quality of life in patients with oculopharyngeal muscular dystrophy (OPMD). METHOD: Intraoral pressure, swallow pressure, and endurance were measured using an Iowa Oral Performance Instrument in participants with OPMD and matched controls. Timed water swallow, weight, and quality of life were also assessed. RESULTS: Participants with OPMD were weaker than controls. Oral weakness impacted strength, swallow pressure, swallow capacity, swallow volume, swallow time, and quality of life. Tongue endurance was not affected by oral weakness. CONCLUSION: This investigation provides further insight into the swallow function of patients with myopathic disease. Muscle fiber loss leads to weakness, which results in reductions in swallow function and quality of life. Weight and endurance are not greatly altered.

Quantitative contributions of the muscles of the tongue, floor-of-mouth, jaw, and velum to tongue-to-palate pressure generation.

PURPOSE: The purpose of this investigation was to evaluate the relationship between tongue-to-palate pressure and the electromyography (EMG) measured from the mylohyoid, anterior belly of the digastric, geniohyoid, medial pterygoid, velum, genioglossus, and intrinsic tongue muscles. Methods Seven healthy adults performed tongue-to-palate pressure tasks at known percentages of their maximum pressure while intramuscular EMG was recorded from the muscles stated above. Multiple regression analysis was performed. RESULTS: Predictors of pressure included the posterior fibers of the genioglossus, mylohyoid, anterior belly of digastric, medial pterygoid, and intrinsic tongue. CONCLUSIONS: Increasing tongue-to-palate pressure coincides with increased muscle activity. Activation of the floor-of-mouth, tongue, and jaw closing muscles increased tongue-to-palate pressure. These findings support the use of a tongue-press exercise to strengthen floor-of-mouth muscles, tongue, and jaw-closing muscles.

Effects of a sour bolus on the intramuscular electromyographic (EMG) activity of muscles in the submental region.

A sour bolus has been used as a modality in the treatment of oropharyngeal dysphagia based on the hypothesis that this stimulus provides an effective preswallow sensory input that lowers the threshold required to trigger a pharyngeal swallow. The result is a more immediate swallow onset time. Additionally, the sour bolus may invigorate the oral muscles resulting in stronger contractions during the swallow. The purpose of this investigation was to compare the intramuscular electromyographic activity of the mylohyoid, geniohyoid, and anterior belly of the digastric muscles during sour and water boluses with regard to duration, strength, and timing of muscle activation. Muscle duration, swallow onset time, and pattern of muscle activation did not differ for the two bolus types. Muscle activation time was more tightly approximated across the onsets of the three muscles when a sour bolus was used. A sour bolus also resulted in a stronger muscle contraction as evidenced by greater electromyographic activity. These data support the use of a sour bolus as part of a treatment paradigm.

Timing of glottic closure during swallowing: a combined electromyographic and endoscopic analysis.

OBJECTIVES: We performed a case series to enhance our understanding of the coupling between neuromuscular events and glottic closure. METHODS: We performed combined flexible video laryngoscopy and electromyography in 4 healthy human subjects. Hooked-wire electrodes were placed in the superior pharyngeal constrictor, longitudinal pharyngeal, cricopharyngeus, thyroarytenoid, genioglossus, suprahyoid, and posterior cricoarytenoid muscles. A flexible endoscope tip was positioned in the oropharyngeal-hypopharyngeal region. The subjects performed multiple trials each of 10-mL normal and super-supraglottic liquid swallows. RESULTS: Arytenoid movement consistently preceded full glottic closure and was associated with cessation of activity of the posterior cricoarytenoid muscle. In 89% of normal swallows, the glottis was partially open in the video frame before bolus passage. The maximum amount of thyroarytenoid electromyographic activity occurred during endoscopic whiteout. When subjects executed a super-supraglottic swallow, early thyroarytenoid activity coincided with arytenoid contact. CONCLUSIONS: The initial medialization of the arytenoids is due to a decrease in motor tone of the posterior cricoarytenoid muscle. Full glottic closure typically occurs late in the process of swallowing, with activation of the thyroarytenoid muscle. Shifting of arytenoid medialization and glottic closure earlier in the super-supraglottic swallow indicates that glottic closure is under significant voluntary control.