Pilot Study of Respiratory-Swallow Coordination in Amyotrophic Lateral Sclerosis.

PURPOSE: Amyotrophic lateral sclerosis (ALS) impacts bulbar and respiratory musculature, which may contribute to impaired swallow function (dysphagia) and respiratory-swallow coordination. The purpose of this pilot study was to examine if respiratory-swallow coordination in individuals with ALS was perturbed compared to healthy controls. We further explored relationships between measures of respiratory function and self-reported swallowing outcomes on respiratory-swallow coordination. METHOD: We employed a cross-sectional design with eight participants with ALS and eight age- and sex-matched healthy participants. Respiratory inductance plethysmography and a nasal cannula were used to capture respiratory-swallow phase patterns during a standardized clinical swallow examination. The advantageous respiratory-swallow phase pattern was defined if exhalation surrounded the swallow (E-E). Spirometry was used to capture indices of respiratory function (forced vital capacity % predicted, peak cough flow [PCF]). Validated questionnaires were used to collect information regarding ALS-related bulbar functional status and swallowing-related concerns. RESULTS: Compared to the matched healthy cohort, individuals with ALS demonstrated higher rates of non-E-E respiratory-swallow phase patterning and worse bulbar/swallow dysfunction. Group (ALS), swallow tasks, and PCF were significantly associated with respiratory-swallow phase pattern. CONCLUSIONS: These preliminary findings support altered respiratory-swallow phase patterning in ALS. Future work should employ an instrumental assessment to quantify swallowing physiology and elucidate the relationship between perturbed respiratory-swallow coordination and swallowing function.

Scoring the Penetration-Aspiration Scale (PAS) in Two Conditions: A Reliability Study.

A widely applied metric for identifying airway invasion events is the Penetration-Aspiration Scale (PAS). PAS scores are often included as primary outcome measures in clinical interventional studies, applied to characterize airway protection in a particular disease, used to establish a normal referent for control group comparisons without dysphagia, and as determinants or predictors of clinical outcomes. Despite the widespread use of the PAS, there is variability in scoring condition. One common method used in research studies includes rater scores applied to each single swallow that occurred during a modified barium swallow study (MBSS) of the same patient. A second common method includes raters scoring single swallow segments that have been spliced from full MBSS from different patients. These single swallow segments are then randomly distributed and the rater is blinded to all swallows that occurred during that patient MBSS. The potential effects of different scoring conditions on rater reliability and score accuracy have not been studied and may have high relevance for the conclusion drawn from the result. The primary aim of this investigation is to determine the impact of two scoring conditions on rater reliability and score accuracy: 1. Contextual, unblinded scoring condition and 2. Randomized, blinded condition. Results of the present study show that no statistically significant differences in PAS rater reliability and score accuracy were found between the two scoring conditions. If findings from this pilot study are reproduced in larger sample sizes, the time and intensity involved in splicing and randomizing MBSS for scoring may not be necessary.

Respiratory-swallow coordination and swallowing impairment in head and neck cancer.

BACKGROUND: The aim of the study was to determine the link between frequency of optimal respiratory-swallow coordination, swallowing impairment, and airway invasion in head and neck cancer (HNC) patients. METHOD: A cross-sectional study of a heterogeneous group of HNC patients (49), precancer (N = 30) or postcancer treatment (N = 29), participated in a single Modified Barium Swallow Study (MBSS) with synchronized respiratory data. RESULTS: Spearman correlation coefficients revealed significant negative correlations between optimal respiratory-swallow phase pattern and objective measures of swallowing impairment: penetration-aspiration scale max, pharyngeal total, and oral total scores with Spearman correlation coefficients of -0.53 (z .001), -0.50 (P < .001), and -0.43 (P = .002), respectively. Optimal respiratory-swallow pattern was significantly decreased (P = .03) in patients after cancer treatment compared with another patient group before cancer treatment. CONCLUSION: These findings indicate that as the percentage of optimal respiratory-swallow phase patterns increase, swallowing impairment decreases in the HNC patient population.

Respiratory-Swallow Training Methods: Accuracy of Automated Detection of Swallow Onset, Respiratory Phase, Lung Volume at Swallow Onset, and Real-Time Performance Feedback Tested in Healthy Adults.

Background Preliminary studies have shown that respiratory-swallow training (RST) is a successful treatment for oropharyngeal head and neck cancer patients with refractory dysphagia. Refining the RST protocol with automated analysis software to provide real-time performance feedback has the potential to improve accessibility, reproducibility, and translation to diverse clinical settings. Method An automated software program for data acquisition and analysis developed to detect swallows, determine respiratory phase, calculate lung volume at the onset of the swallow, and provide real-time performance feedback was tested for feasibility in a small cohort of healthy adults. Outcome Measures Percent difference in swallow detection and accuracy of real-time performance feedback of respiratory phase and lung volume at swallowing onset between the automated software and the manual gold standard method were determined. Results The automated software program accurately detected the onset of the swallow on 91% of the swallows completed during the training trials. Feedback of respiratory phase and lung volume was accurate on 94% of the trials in which the swallow was accurately detected. Conclusions This novel, automated, and real-time RST software successfully detected the onset of the swallow, respiratory phase, and lung volume at swallow onset and provided appropriate real-time performance feedback with a high degree of accuracy in healthy adults. The software has the potential to improve the accessibility, efficiency, and translation of RST to diverse patient populations.

Respiratory Phase and Lung Volume Patterns During Swallowing in Healthy Adults: A Systematic Review and Meta-Analysis.

Purpose The coordination of respiration with swallowing is critical for facilitation of airway protection and the efficiency of movements that propel ingested material through the upper aerodigestive tract. Confirmation of a predominant pattern in healthy adults provides a platform for comparison to aberrant patterns observed in the population with swallowing impairment (dysphagia). Method A comprehensive search of published research in MEDLINE via PubMed 1946-2018, Embase 1947-2018, and Proquest Dissertations & Theses Global 1861-2018 was completed. Results Thirty-seven articles meeting inclusion criteria were selected for data extraction, and the findings were reviewed. In addition, a meta-analysis of the data was completed. A significantly higher occurrence ( p < .001) of expiration prior to and following the swallow was found when compared to 3 other patterns. The predominance of the pattern was influenced by increases in bolus volume when controlling for participant sample size. Conclusion Determination of this predominant pattern provides a normative framework for evaluating respiratory-swallow coordination in adults across the age span and highlights the relevance for assessing and incorporating respiratory swallowing coordination during assessment and interventions.

Oropharyngeal swallow physiology and swallowing-related quality of life in underweight patients with concomitant advanced chronic obstructive pulmonary disease.

Background: Swallowing impairment (dysphagia) has been associated with COPD and may contribute to exacerbations of this chronic and progressive disease. Further, risk of mortality increases with concomitant presence of cachexia in the COPD population. The purpose of this prospective study was to depict oropharyngeal swallowing physiology in underweight patients with stable but advanced-stage COPD. Patients and methods: Ten underweight patients with stable but advanced COPD underwent a modified barium swallow study. Analysis of oropharyngeal swallowing function was completed using the standardized Modified Barium Swallow Impairment Profile and the Penetration-Aspiration Scale. Scores from the Dysphagia Handicap Index and 10-item Eating Assessment Tool were collected to assess patient perception of swallowing difficulty. Findings were compared to age- and sex-matched healthy controls. Results: Significantly higher MBSImP oral total scores (P=0.007) were observed in COPD patients compared to matched controls, but no difference was observed in pharyngeal total scores (P=0.105). Patients with COPD had significantly higher maximum PAS scores compared with controls (P=0.030). There was no significant difference in EAT-10 or DHI scores between patients with COPD and controls (P=0.41 and P=0.08, respectively). Conclusion: Underweight patients with severe but stable COPD present with dysphagia that may not be recognized by the patient. Further investigation is needed to elucidate the interaction between the respiratory-swallowing systems, how muscular weakness may contribute to swallowing impairment, and responsiveness to swallowing treatment.