Respiratory-Swallow Coordination in Individuals with Parkinson's Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: Swallowing impairment, including altered physiology and aspiration, occur across the progression of Parkinson's disease (PD). The phase of respiration during which a swallow is initiated has been linked to swallowing impairment and aspiration in cohorts with dysphagia following stroke and head and neck cancer treatment, but has been understudied in PD. If similar findings are shown in individuals with PD, the implications for swallowing assessment and treatment are significant. OBJECTIVE: The aim of this systematic review and meta-analysis of literature was to examine respiratory-swallow coordination measures and potential implications on swallowing physiology in individuals with PD. METHODS: An extensive search of 7 databases (PubMed, EMBASE, Central, Web of Science, ProQuest Dissertations & Theses, Scopus, and CINAHL) with predetermined search terms was conducted. Inclusion criteria were individuals with PD and the use of objective evaluations of respiratory-swallow coordination. RESULTS: Of the 13,760 articles identified, 11 met the inclusion criteria. This review supports the presence of atypical respiratory swallow patterning, respiratory pause duration and lung volume at swallow initiation in individuals with PD. The meta-analysis estimated an occurrence of 60% of non-expiration-expiration and 40% of expiration-expiration respiratory phase patterns surrounding swallowing. CONCLUSION: Although this systematic review supports the occurrence of atypical respiratory-swallow coordination in individuals with PD, the evidence is limited by the variability in the methods of data acquisition, analysis, and reporting. Future research examining the impact of respiratory swallow coordination on swallowing impairment and airway protection using consistent, comparable, and reproducible methods and metrics in individuals with PD is warranted.

Day-to-Day Variability of Clinical Feeding and Swallowing Performance in School-Age Self-Feeding Children With Cerebral Palsy.

PURPOSE: We aimed to examine the day-to-day variability of feeding and swallowing performance and mealtime duration in school-age self-feeding children with spastic cerebral palsy (SCP) across 15 days. METHOD: Thirteen children with SCP (ages 5;10 [years;months]-17;6) participated. Children were divided into unilateral (UCP, n = 6) and bilateral (BCP, n = 7) SCP groups. Feeding/swallowing assessments using the Dysphagia Disorder Survey (DDS) were conducted and total mealtime durations (TMDs) were calculated for all days. DDS Part 1 (factors related to feeding) and DDS Part 2 (signs of oropharyngeal difficulties) components were rated. Mixed-effects models were used to compare group means and estimate between- and within-subject variances in each group. Likelihood ratio tests were used to determine best covariance structure and compare variance types across groups. RESULTS: Within-subject variance for all three variables, DDS Part 1, 2, and TMD, across days was larger in the BCP group than the UCP group (Part 1: p = .0036, Part 2: p = .0002, and TMD: p = .0005) and the between-subject variance was larger in the BCP group for DDS Part 2 (p = .0362). The UCP group presented with lower (milder) DDS scores (Part 1: p = .0160; Part 2: p = .0141) and shorter TMD (p = .0077) than the BCP group across days. Furthermore, both groups exhibited greater variability in DDS Part 2 than 1 (p < .0001). CONCLUSION: These preliminary results emphasize the need to account for day-to-day variability when evaluating swallowing especially in children with BCP and provide preliminary ranges of performance that could be useful for clinical prognosis and future treatment research. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.21669611.

Cross-System Integration of Respiration and Deglutition: Function, Treatment, and Future Directions.

Swallowing occurs preferentially in the expiratory phase of the quiet breathing cycle and at mid-to-low tidal volume. This coordinative pattern imparts important biomechanical advantages to swallowing and airway protection and facilitate laryngeal elevation, laryngeal vestibular and vocal fold closure, and cricopharyngeal sphincter opening. This preferred coordinative relationship between breathing and swallowing is impaired in a variety of patient populations, including head and neck cancer survivors with dysphagia. We developed a training protocol to re-establish more optimal phasing of swallowing with breathing in these patients with striking outcomes, including reduced swallowing physiological impairments and improved airway protection. This motivated us to continue to refine and expand this training protocol and develop new assistive technologies for swallowing monitoring outside of the lab. In this review, we highlight the origins of our optimal respiratory-swallowing coordination hypothesis, describe the biomechanical advantages it provides, carefully describe our training protocol and findings, and chart a course for the next phase of this work. Our overall goal is to harness technology combined with carefully constructed learning paradigms to improve the lives of patients with impaired respiratory-swallowing coordination consequent to a variety of pathologies including head and neck cancer and degenerative neurological conditions such as Parkinson's disease.

Determining Swallowing Biomechanics Underlying Modified Barium Swallow Impairment Profile Scoring Using Computational Analysis of Swallowing Mechanics.

PURPOSE: The elements of impaired swallowing biomechanics are visually assessed and scored by clinicians using a standardized and validated tool for assessing type and severity of physiological impairments using the Modified Barium Swallow Impairment Profile (MBSImP). However, the functional anatomical correlates that underly noted impairments using MBSImP scoring have not been measured. The purpose of this study was to determine whether differences in MBSImP component scores represent differences in underlying swallowing mechanics as measured by computational analysis of swallowing mechanics (CASM) to better define underlying mechanisms of impairment. METHOD: A retrospective analysis of modified barium swallow studies from physician-referred adult patients with dysphagia was scored using the MBSImP for laryngeal elevation, anterior hyoid excursion, epiglottic movement, pharyngoesophageal segment opening, and tongue base retraction. A canonical variate analysis (CVA) was performed to determine the movement of anatomical landmarks associated with MBSImP component scores using the CASM method. Mahalanobis distances (D) were then used to detect differences among MBSImP scores for each component assessed. RESULTS: CVA showed significant differences (p < .0001) in Mahalanobis distance (D > 1) between MBSImP component scores of 0-1, 0-2, 0-3, or 0-4, as applicable, depending on the component. Discriminant function analyses revealed concomitant increase/worsening in MBSImP score with changes in anatomical positioning of structures. CONCLUSIONS: Ratings of swallowing impairment and physiology using the MBSImP have distinct biomechanical correlates with anatomical movements of swallowing. These data further demonstrate how swallowing mechanics are highly interrelated. Understanding these linkages between anatomical and physiological movement within impaired swallowing biomechanics is essential in more specific characterization and treatment of dysphagia. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.20816788.

Soft skin-interfaced mechano-acoustic sensors for real-time monitoring and patient feedback on respiratory and swallowing biomechanics.

Swallowing is a complex neuromuscular activity regulated by the autonomic nervous system. Millions of adults suffer from dysphagia (impaired or difficulty swallowing), including patients with neurological disorders, head and neck cancer, gastrointestinal diseases, and respiratory disorders. Therapeutic treatments for dysphagia include interventions by speech-language pathologists designed to improve the physiology of the swallowing mechanism by training patients to initiate swallows with sufficient frequency and during the expiratory phase of the breathing cycle. These therapeutic treatments require bulky, expensive equipment to synchronously record swallows and respirations, confined to use in clinical settings. This paper introduces a wireless, wearable technology that enables continuous, mechanoacoustic tracking of respiratory activities and swallows through movements and vibratory processes monitored at the skin surface. Validation studies in healthy adults (n = 67) and patients with dysphagia (n = 4) establish measurement equivalency to existing clinical standard equipment. Additional studies using a differential mode of operation reveal similar performance even during routine daily activities and vigorous exercise. A graphical user interface with real-time data analytics and a separate, optional wireless module support both visual and haptic forms of feedback to facilitate the treatment of patients with dysphagia.

Validation of a Novel Wearable Electromyography Patch for Monitoring Submental Muscle Activity During Swallowing: A Randomized Crossover Trial.

Purpose Surface electromyography (sEMG) is often used for biofeedback during swallowing rehabilitation. However, commercially available sEMG electrodes are not optimized for the head and neck area, have rigid form, and are mostly available in large medical centers. We developed an ultrathin, soft, and flexible sEMG patch, specifically designed to conform to the submental anatomy and which will be ultimately incorporated into a telehealth system. To validate this first-generation sEMG patch, we compared its safety, efficiency, and signal quality in monitoring submental muscle activity with that of widely used conventional sEMG electrodes. Method A randomized crossover design was used to compare the experimental sEMG patch with conventional (snap-on) sEMG electrodes. Participants completed the same experimental protocol with both electrodes in counterbalanced order. Swallow trials included five trials of 5- and 10-ml water. Comparisons were made on (a) signal-related factors: signal-to-noise ratio (SNR), baseline amplitude, normalized mean amplitude, and sEMG burst duration and (b) safety/preclinical factors: safety/adverse effects, efficiency of electrode placement, and satisfaction/comfort. Noninferiority and equivalence tests were used to examine signal-related factors. Paired t tests and descriptive statistics were used to examine safety/preclinical factors. Results Forty healthy adults participated (24 women, M age = 67.5 years). Signal-related factors: SNR of the experimental patch was not inferior to the SNR of the conventional electrodes (p < .0056). Similarly, baseline amplitude obtained with the experimental patch was not inferior to that obtained with conventional electrodes (p < .0001). Finally, normalized amplitude values were equivalent across swallows (5 ml: p < .025; 10 ml: p < .0012), and sEMG burst duration was also equivalent (5 ml: p < .0001; 10 ml: p < .0001). Safety/preclinical factors: The experimental patch resulted in fewer mild adverse effects. Participant satisfaction was higher with the experimental patch (p = .0476, d = 0.226). Conclusions Our new wearable sEMG patch is equivalent with widely used conventional sEMG electrodes in terms of technical performance. In addition, our patch is safe, and healthy older adults are satisfied with it. With lessons learned from the current COVID-19 pandemic, efforts to develop optimal swallowing telerehabilitation devices are more urgent than ever. Upon further validation, this new technology has the potential to improve rehabilitation and telerehabilitation efforts for patients with dysphagia. Supplemental Material https://doi.org/10.23641/asha.12915509.

Flexible submental sensor patch with remote monitoring controls for management of oropharyngeal swallowing disorders.

Successful rehabilitation of oropharyngeal swallowing disorders (i.e., dysphagia) requires frequent performance of head/neck exercises that primarily rely on expensive biofeedback devices, often only available in large medical centers. This directly affects treatment compliance and outcomes, and highlights the need to develop a portable and inexpensive remote monitoring system for the telerehabilitation of dysphagia. Here, we present the development and preliminarily validation of a skin-mountable sensor patch that can fit on the curvature of the submental (under the chin) area noninvasively and provide simultaneous remote monitoring of muscle activity and laryngeal movement during swallowing tasks and maneuvers. This sensor patch incorporates an optimal design that allows for the accurate recording of submental muscle activity during swallowing and is characterized by ease of use, accessibility, reusability, and cost-effectiveness. Preliminary studies on a patient with Parkinson's disease and dysphagia, and on a healthy control participant demonstrate the feasibility and effectiveness of this system.

Novel Mealtime Duration Measures: Reliability and Preliminary Associations With Clinical Feeding and Swallowing Performance in Self-Feeding Children With Cerebral Palsy.

Purpose: The purpose of this study is to examine (a) the reliability of newly developed measures of mealtime duration and (b) their relationship to clinical feeding/swallowing performance in children with spastic cerebral palsy (SCP). Method: Seventeen self-feeding children (9 boys, 8 girls) with SCP (age range = 5;1 [years;months] to 17;6, Gross Motor Function Classification System range = I-IV) were assessed during mealtimes using the Dysphagia Disorder Survey (DDS; Sheppard, Hochman, & Baer, 2014). Children were divided into 2 groups, children with primarily unilateral or bilateral brain involvement. Duration measures included mealtime duration and total sip/bite duration for each bolus type (liquid and solid). Results: Excellent intra- and inter-rater reliability for all duration measures was observed (intraclass correlation coefficient [ICC] = 1.00 and 0.955, respectively, for mealtime duration; ICC = 1.00 and 0.963, respectively, for solid/bite duration; ICC = 1.00 and 0.957, respectively, for liquid/sip duration). Positive correlations were found between total mealtime duration and DDS Part 1, rs = .514 [.045-.797], p = .035; Part 2, rs = .528 [.064-.804], p = .029; and total scores, rs = .665 [.271-.868], p = .004, and between total solid/bite duration and DDS Part 1, rs = .579 [.137-.828], p = .015; Part 2, rs = .620 [.199-.847], p = .007; and total scores, rs = .762 [.444-.909], p < .001. Children with unilateral brain involvement exhibited significantly lower DDS total (p = .049) and Part 2 scores (p = .026), indicating better feeding/swallowing performance/skills. They also had shorter mealtime duration (p = .019) and solid/bite duration (p = .025) compared with children with bilateral involvement. Conclusions: Our new mealtime duration measures are reliable and correlate with feeding/swallowing performance in a sample of self-feeding children with SCP. Therefore, they may be useful supplements to feeding/swallowing assessments for this population. Supplemental Material: https://doi.org/10.23641/asha.5715076.

First Step in Telehealth Assessment: A Randomized Controlled Trial to Investigate the Effectiveness of an Electronic Case History Form for Dysphagia.

The need for developing effective telehealth tools for dysphagia management is high not only for people who live in rural areas, but also for individuals with mobility/access limitations. We aimed to develop an electronic case History Tool/form (thereafter, e-HiT) for dysphagia, and compare its effectiveness with its paper-based version (PBV) on completion time, completeness, independence, and patient perceptions/satisfaction. Secondarily, we examined associations between the aforementioned variables and predictor variables, such as age, cognition, and computer/internet use. Forty adults who expressed concerns with eating/swallowing participated. To compare both versions, a randomized, controlled two-period crossover design was used. In Visit 1, Group A completed the e-HiT and Group B completed the PBV. In Visit 2, Group A completed the PBV and Group B completed the e-HiT. A satisfaction survey was completed post visits. There were no statistically significant differences for completion time (p = 0.743), completeness (p = 0.486), and independence (p = 0.738). Patient perception/satisfaction was significantly higher with the e-HiT (p = 0.004). In addition, a significant association was found between completion time and age (p = 0.0063). Our results indicate that completing the e-HiT is as time efficient as completing the PBV and that both forms elicit the same amount of information with no or minimal support. Also, completion of the e-HiT yielded significantly higher satisfaction responses. This is the first study documenting the effectiveness of the e-HiT for outpatients with dysphagia, providing evidence that the first step of a swallowing assessment-case history completion-can be effectively completed via telehealth by individuals with reliable internet connection and basic computer literacy skills.

A telehealth approach to conducting clinical swallowing evaluations in children with cerebral palsy.

BACKGROUND: Accurate and timely evaluation of dysphagia in children with cerebral palsy (CP) is critical. For children with limited access to quality healthcare, telehealth is an option; however, its reliability needs to be investigated. AIM: To test the reliability of an asynchronous telehealth model for evaluating dysphagia in children with CP using a standardized clinical assessment. METHODS AND PROCEDURES: Nineteen children (age range 6.9-17.5) were assessed at three mealtimes via the Dysphagia Disorder Survey (DDS) by three clinicians (face-to-face evaluations). Mealtimes were video-recorded to allow asynchronous evaluations by a remote clinician who also completed approximately 1/3 of face-to-face evaluations. Agreement was tested on DDS variables and dysphagia severity. OUTCOMES AND RESULTS: Results revealed substantial to excellent agreement between face-to-face and remote assessments by the same rater (78-100%, KW=0.64-1) on all, but two variables (oral transport and oral pharyngeal swallow) and by different raters (69-89%, KW=0.6-0.86) on all but one variable (orienting). For dysphagia severity, intrarater agreement was excellent (100%, KW=1); interrater agreement was substantial (85%; KW=0.76). CONCLUSIONS AND IMPLICATIONS: Asynchronous clinical swallowing evaluations using standardized tools have acceptable levels of agreement with face-to-face evaluations, and can be an alternative for children with limited access to expert swallowing care.

The Intensive Dysphagia Rehabilitation Approach Applied to Patients With Neurogenic Dysphagia: A Case Series Design Study.

OBJECTIVE: To examine the effects of the Intensive Dysphagia Rehabilitation approach on physiological and functional swallowing outcomes in adults with neurogenic dysphagia. DESIGN: Intervention study; before-after trial with 4-week follow-up through an online survey. SETTING: Outpatient university clinics. PARTICIPANTS: A consecutive sample of subjects (N=10) recruited from outpatient university clinics. All subjects were diagnosed with adult-onset neurologic injury or disease. Dysphagia diagnosis was confirmed through clinical and endoscopic swallowing evaluations. No subjects withdrew from the study. INTERVENTIONS: Participants completed the 4-week Intensive Dysphagia Rehabilitation protocol, including 2 oropharyngeal exercise regimens, a targeted swallowing routine using salient stimuli, and caregiver participation. Treatment included hourly sessions twice per week and home practice for approximately 45 min/d. MAIN OUTCOME MEASURES: Outcome measures assessed pre- and posttreatment included airway safety using an 8-point Penetration Aspiration Scale, lingual isometric pressures, self-reported swallowing-related quality of life (QOL), and level of oral intake. Also, patients were monitored for adverse dysphagia-related effects. QOL and adverse effects were also assessed at the 4-week follow-up (online survey). RESULTS: The Intensive Dysphagia Rehabilitation approach was effective in improving maximum and mean Penetration Aspiration Scale scores (P<.05, η(2)=.8146 and P<.05, η(2)=.799708, respectively) and level of oral intake (P<.005, Cohen d=-1.387). Of the 5 patients who were feeding tube dependent initially, 2 progressed to total oral nutrition, and 2 progressed to partial oral nutrition. One patient remained tube dependent. QOL was significantly improved at the 4-week follow-up (95% confidence interval, 6.38-14.5; P<.00), but not at the posttreatment. No adverse effects were observed/reported. CONCLUSIONS: The Intensive Dysphagia Rehabilitation approach was safe and improved physiological and some functional swallowing outcomes in our sample; however, further investigation is needed before it can be widely applied.