Voluntary Cough and Swallowing Function Characteristics of Acute Stroke Patients Based on Lesion Type

Respiratory Strength Training Versus Respiratory Relaxation Training in the Rehabilitation of Physical Impairment, Function, and Return to Participation After Stroke: Protocol for a Randomized Controlled Trial

BACKGROUND

Persistent disability in chronic stroke survivors is often attributed to arm or leg weakness; however, respiratory muscle weakness also impedes poststroke rehabilitation, reduces quality of life, and increases the risk of health complications. Respiratory complications are common after stroke and place patients at risk for both prolonged functional disability and mortality. In addition, stroke survivors face ongoing cardiovascular disease that places them at risk for recurrent stroke.

OBJECTIVE

The study aims to compare the effects of 2 respiratory training programs, paired with individualized flexibility, strengthening, and cardiovascular exercise programs, on physiologic, activity, and societal participation outcomes in chronic stroke survivors.

METHODS

This study will be a randomized controlled trial. Participants are 80 community-dwelling adults with chronic stroke. In conjunction with a 24-session (3 times/week for 8 weeks), American Heart Association-informed, whole-body exercise program, participants will be randomized to receive either respiratory strength training or respiratory relaxation training. Study intervention will be directed by a physical therapist and take place in a community fitness center. Outcome assessments will occur in a clinical research center. The primary outcome measure is maximal respiratory pressure. Secondary outcome measures include airway clearance, walking endurance, spatial-temporal gait characteristics, community walking, functional strength and fatigue, depression, and societal participation measures. Longer-term societal participation is a complex domain that may be influenced by other factors beyond physical function. Participants' health status will be monitored for 1 year following the intervention for falls, respiratory illness, and hospitalizations. Additional subanalyses will evaluate the effect of smoke exposure on short- and long-term outcomes. Outcome assessors are blinded to group assignments. Respiratory relaxation training is an active comparator, but no pure control group is included.

RESULTS

This study was funded in March 2020 with enrollment commencing in November 2020. Completion of enrollment is projected for May 2025 with a study projected end date of April 2026. Published results are anticipated in Fall 2026.

CONCLUSIONS

Results from this study will improve our understanding of the additive benefits of respiratory exercises on short- and long-term physiologic, functional, and societal gains for these individuals. These data will be instructive to meet a current unmet rehabilitative need to promote patient-centered care and contribute to decreasing morbidity and mortality in chronic stroke survivors.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT05819333; https://clinicaltrials.gov/study/NCT05819333.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/59749.

Utilizing Pulmonary Function Parameters to Predict Dysphagia in Individuals With Cervical Spinal Cord Injuries

Objective

To utilize pulmonary function parameters as predictive factors for dysphagia in individuals with cervical spinal cord injuries (CSCIs).

Methods

Medical records of 78 individuals with CSCIs were retrospectively reviewed. The pulmonary function was evaluated using spirometry and peak flow meter, whereas the swallowing function was assessed using a videofluoroscopic swallowing study. Participants were divided into the non-penetration-aspiration group (score 1 on the Penetration-Aspiration Scale [PAS]) and penetration-aspiration group (scores 2–8 on the PAS). Individuals with pharyngeal residue grade scores >1 were included in the pharyngeal residue group.

Results

The mean age was significantly higher in the penetration-aspiration and pharyngeal residue groups. In this study, individuals with clinical features, such as advanced age, history of tracheostomy, anterior surgical approach, and higher neurological level of injury, had significantly more penetration-aspiration or pharyngeal residue. Individuals in the penetration-aspiration group had significantly lower peak cough flow (PCF) levels. Individuals in the pharyngeal residue group had a significantly lower forced expiratory volume in 1 second (FEV1). According to the receiver operating characteristic curve analysis of PCF and FEV1 on the PAS, the cutoff value was 140 L/min and 37.5% of the predicted value, respectively.

Conclusion

Low PCF and FEV1 values may predict the risk of dysphagia in individuals with CSCIs. In these individuals, active evaluation of swallowing is recommended to confirm dysphagia.

Peak Voluntary Cough Flow and Oropharyngeal Dysphagia as Risk Factors for Pneumonia

Objective

To investigate the relationship between voluntary peak cough flow (PCF), oropharyngeal dysphagia, and pneumonia in patients who were evaluated with videofluoroscopic swallowing study (VFSS).

Methods

Patients who underwent both VFSS and PCF measurement on the same day were enrolled retrospectively (n=821). Pneumonia (n=138) and control (n=683) groups were assigned based on presence of pneumonia within 1 month from the date of VFSS assessment. In addition, sex, age (<65 and ≥65 years), preceding conditions, modified Barthel Index (MBI), Mini-Mental State Examination (MMSE), PCF value (<160, ≥160 and <270, and ≥270 L/min), and presence of aspiration/penetration on VFSS were reviewed.

Results

Pneumonia group was more likely to be male (n=108; 78.3%), ≥65 years (n=121; 87.7%), with neurodegenerative (n=25; 18.1%) or other miscellaneous diseases (n=50; 36.2%), and in poor functional level with lower value of MBI (39.1±26.59). However, MMSE was not significantly different in comparison to that of the control group. The pneumonia group was also more likely to have dysphagia (82.6%) and lower value of PCF (<160 L/min, 70.3%). In multivariable logistic regression analysis, male sex (odd ratio [OR]=6.62; 95% confidence interval [CI], 2.70–16.26), other miscellaneous diseases as preceding conditions (OR=2.52; 95% CI, 1.14–5.58), dysphagia (OR=3.82; 95% CI, 1.42–10.23), and PCF <160 L/min (OR=14.34; 95% CI, 1.84–111.60) were factors significantly related with pneumonia.

Conclusion

Impaired swallowing and coughing function showed an independent association with the development of pneumonia. Patients with PCF <160 L/min require more attention with lung care and should be encouraged with voluntary coughing strategy to prevent possible pulmonary complications.

Assessment of cough in head and neck cancer patients at risk for dysphagia-An overview

BACKGROUND

This literature review explores the terminology, the neurophysiology, and the assessment of cough in general, in the framework of dysphagia and regarding head and neck cancer patients at risk for dysphagia. In the dysphagic population, cough is currently assessed perceptually during a clinical swallowing evaluation or aerodynamically.

RECENT FINDINGS

Recent findings have shown intra and inter-rater disagreements regarding perceptual scoring of cough. Also, aerodynamic measurements are impractical in a routine bedside assessment. Coughing, however, is considered to be a clinically relevant sign of aspiration and dysphagia in head and cancer patients treated with concurrent chemoradiotherapy.

CONCLUSION

This article surveys the literature regarding the established cough assessment and stresses the need to implement innovative methods for assessing cough in head and neck cancer patients treated with concurrent chemoradiotherapy at risk for dysphagia.

Use of the Penetration-Aspiration Scale in Dysphagia Research: A Systematic Review

The penetration-aspiration scale (PAS) is an 8-point scale used to characterize the depth and response to airway invasion during videofluoroscopy. Though widely used in the field of deglutition, there is a lack of consensus regarding the statistical properties of the scale. In order to better understand the state of the literature and the statistical use of the PAS, a systematic review was undertaken to descriptively examine trends in statistical and reporting practices of the PAS since its inception. Online databases were searched for studies citing the original PAS article, which yielded 754 unique articles. Of these, 183 studies were included in the review. Results showed inconsistencies in the statistical use of the scale; 79 studies treated the PAS as ordinal, 71 as categorical, and 49 as interval. Ten types of categorizations were identified. Reporting of power analyses (9%), as well as inter- (26%) and intra-rater (17%) reliability, was uncommon. Among studies that administered multiple bolus volumes or consistencies, 55% reported PAS analyses at the participant/group level only. This review confirms the existence of discrepancies in the statistical treatment of the PAS. A lack of consensus among researchers limits comparisons between studies. The approach to handling this scale dictates the statistical tests used, potentially affecting results and interpretations. Consistent application of statistically sound approaches to PAS analyses is vital for the future of deglutition research.

The therapeutic effect and complications of oro-esophageal tube training in stroke patients

Background: Patients with severe dysphagia after stroke are usually fed using a nasogastric tube. However, this method is inconvenient and causes complications. The oro-esophageal (OE) tube has been used as an alternative parenteral feeding method for patients for whom safe oral feeding is impossible. This study aimed to evaluate the therapeutic effects and complications of OE tube feeding in stroke patients with dysphagia.

Methods: This study was designed as a retrospective medical chart review of dysphagic stroke patients who were recommended for OE tube feeding. Thirty-eight stroke patients were recommended for OE tube feeding according to videofluoroscopic swallowing study (VFSS) findings. Of those patients, 17 received OE tube feeding training and conventional dysphagia therapy. Follow-up VFSSs were performed sequentially based on the patients’ conditions. When a patient was able to swallow therapeutic foods with specific viscosities during the VFSS, oral feeding was considered to be initiated. Patients were divided into two groups according to final feeding methods.

Results: Seventeen patients attempted OE tube feeding. Among them, 64.7% of the patients could change to full oral feeding at their follow-up VFSS evaluation. Additionally, 70.6% of the patients showed gastroesophageal reflux disease regardless of whether they changed to oral feeding. On individual items of the Functional Dysphagia Scale, both groups showed significant improvements in the triggering of pharyngeal swallowing, the amount of residue, and the pharyngeal transit time. These functions were better improved in the patients who could change to oral feeding than in those who could not. Both groups showed significant aggravation of nasal penetration.

Conclusion: Our study quantitatively shows the therapeutic effects and complications of OE tube training. OE tube feeding can facilitate the swallowing process and assist patients in transitioning to oral feeding. This easy-to-apply technique may significantly impact future treatment strategies in stroke patients with severe dysphagia.

Changes in Swallowing and Cough Functions Among Stroke Patients Before and After Tracheostomy Decannulation

We investigated the functional changes in swallowing and voluntary coughing before and after tracheostomy decannulation among stroke patients who had undergone a tracheostomy. We also compared these functions between stroke patients who underwent tracheostomy tube removal and those who did not within 6 months of their stroke. Seventy-seven stroke patients who had undergone a tracheostomy were enrolled. All patients were evaluated by videofluoroscopic swallowing studies and a peak flow meter through the oral cavity serially until 6 months after their stroke. During the intensive rehabilitation period, if a patient satisfied the criteria for tracheostomy tube removal, the tube was removed. The patients were divided into the 'decannulated' group and the 'non-decannulated' group according to their tracheostomy tube removal status. In the decannulated group, swallowing function did not change before and after tracheostomy decannulation; however, cough function was significantly improved after decannulation. Although both groups exhibited functional improvement in swallowing and coughing over time, the improvement in the decannulated group was more significant than the improvement in the non-decannulated group. Our results revealed that stroke patients who had better functional improvement in swallowing and coughing were more likely to be potential candidates for tracheostomy decannulation. Stroke patients who recovered from neurogenic dysphagia, they were no longer affected by the mechanical effect of the tracheostomy tube on swallowing function. This study suggests that if patients show improvement in swallowing and coughing after their stroke, a multidisciplinary approach to tracheostomy decannulation would be needed to achieve better rehabilitation outcomes.

Usefulness of Early Videofluoroscopic Swallowing Study in Acute Stroke Patients With Dysphagia

Objective

To demonstrate the usefulness of early videofluoroscopic swallowing study (VFSS) and to investigate change patterns in dietary methods in stroke patients with dysphagia.

Methods

The VFSS was performed within 7 days of stroke onset in neurologically stable patients. The patients were divided into three groups according to type of brain lesion: cortical lesion (CL), subcortical lesion (SCL), and brainstem/cerebellar lesion (BCL). Based on the VFSS results, this study investigated change patterns in feeding method and discrepancies in the aspiration risk predicted by the Water Swallowing Test (WST) and the VFSS. Complications, such as aspiration pneumonia, were also evaluated.

Results

A total of 163 patients met the inclusion criteria and the VFSS was performed within 7 days of stroke. Patients considered at risk for aspiration (Penetration-Aspiration Scale [PAS] scores of 6 to 8) were found in all three groups using the VFSS (47.5% of the CL group, 59.3% of the SCL group, and 47.9% of the BCL group). After early VFSS, 79.7% of the patients were assessed to require restricted feeding methods. A 19.0% discrepancy was found between the WST and VFSS results. At 3-week follow-up after the VFSS, aspiration pneumonia was observed in 12 patients (7.4%) with restricted feeding methods.

Conclusion

Early VFSS during the acute period can facilitate determination of the most appropriate feeding method, and support effective dysphagia management for stroke patients.

The accuracy of the bedside swallowing evaluation for detecting aspiration in survivors of acute respiratory failure

BACKGROUND

Dysphagia with subsequent aspiration occurs in up to 60% of acute respiratory failure (ARF) survivors. Accurate bedside tests for aspiration can reduce aspiration-related complications while minimizing delay of oral nutrition. In a cohort of ARF survivors, we determined the accuracy of the bedside swallowing evaluation (BSE) and its components for detecting aspiration.

METHODS

Patients who were extubated after at least 24hours of mechanical ventilation were eligible for enrollment. Within 3 days of extubation, patients underwent comprehensive BSE including 3-oz water swallowing test (3-WST), followed by a criterion standard test for aspiration, flexible endoscopic evaluation of swallowing (FEES).

RESULTS

Forty-five patients were included in the analysis. Median patient age was 55years (interquartile range, 47-65). Median duration of mechanical ventilation was 3.3days (interquartile range 1.8-6.0). Fourteen patients (31%) aspirated on FEES. Physical examination findings on BSE and abnormal swallowing during trials of different consistencies were variably associated with aspiration. Compared with FEES, the 3-WST yielded a sensitivity of 77% (95% confidence interval [CI], 50%-92%), specificity of 65% (95% CI, 47%-79%), and an area under the receiver operating characteristic curve (AUC) of 0.71; a speech language pathologist's recommendation for altered diet yielded a sensitivity of 86% (95% CI, 60%-96%), a specificity of 52% (95% CI, 35%-68%), and an AUCof 0.69; an speech language pathologist's recommendation for nil per os (nothing by mouth) yielded a sensitivity of 50% (95% CI, 27%-73%), a specificity of 94% (95% CI, 79%-98%), and an AUCof 0.72.

CONCLUSIONS

The BSE and its components, including the 3-WST, demonstrated variable accuracy for aspiration in survivors of ARF. Investigation to determine the optimal noninvasive test for aspiration in ARF survivors is warranted.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov identifier: NCT02363686, Aspiration in Acute Respiratory Failure Survivors.

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.

Kinematic analysis of swallowing in the patients with esophagectomy for esophageal cancer

The aim of this study is to reveal the mechanism of esophagectomy-mediated swallowing motion disorders. Forty-seven patients who underwent 3-stage esophagectomy with cervical anastomosis and VFSS for esophageal cancer were selected. Twenty-three patients displayed subglottic aspiration (aspiration group) and the other 24 patients did not show any aspiration or penetration in the videofluoroscopic swallowing study after esophagectomy (no aspiration group). For comparison, 27 healthy volunteers (normal group) were included. Maximal anterior displacement of the hyoid (MADH), maximal superior displacement of the hyoid (MSDH), maximal rotation of the epiglottis (MRE) and pharyngeal delay time (PDT) were measured by image J software. MADH, MRE, and PDT in normal group were significantly different from those in aspiration and no aspiration groups (P<0.001). The normal group displayed a significantly different PDT compared to the no aspiration and aspiration groups, and the no aspiration group had a significantly different PDT compared to the aspiration group (P<0.001). The mechanism of swallowing motion disorders caused by the esophagectomy in esophageal cancer includes the decreased anterior movement of the hyoid and rotation of the epiglottis caused by the prolonged operation time and delayed pharyngeal reflex caused by the laryngeal sensory disturbance. Among them, the main mechanism of subglottic aspiration after esophagectomy is the delayed pharyngeal reflex.