Dysphagia in stroke patients

A review of swallow timing in the elderly

Many studies evaluate dysphagia in elderly patients and compare their swallowing to younger controls to assess the degree of swallowing impairment. Previous research suggests that changes should be expected in swallowing due to aging, and these changes need to be considered when performing swallowing assessments. A systematic review was conducted to elucidate the timing of swallowing in healthy. A comprehensive multiengine literature search was conducted to find articles studying swallowing in the healthy elderly, which yielded 22,852 articles of which 11 were judged to be relevant. Only articles using videofluoroscopy as an assessment method for swallowing timing were included. The articles underwent detailed review for study quality and data extraction. The eleven studies contained data for 32 different parameters, and 10 of the 11 studies compared elderly subjects to a younger group. Timing measures from the studies were compiled for analysis. In general, bolus transit times do not appear to change with age. Of note, elderly subjects tended to have a significantly delayed swallow response times and longer duration of upper esophageal sphincter opening. Results showed a large degree of variability across studies for each of the timing measures. Confidence intervals for timing in healthy older participants were computed across studies. Potential sources of variation were identified, including methodological, stimulus-related and participant-related sources. The results suggests that aging affects only a few very specific swallowing timing parameters, and many parameters appear to be unaffected by aging. Therefore, significant differences from a young reference sample should be interpreted as dysphagia rather than normal changes due to aging.

Comparison of swallowing functions between brain tumor and stroke patients

OBJECTIVE

To compare the swallowing functions according to the lesion locations between brain tumor and stroke patients.

METHODS

Forty brain tumor patients and the same number of age-, lesion-, and functional status-matching stroke patients were enrolled in this study. Before beginning the swallowing therapy, swallowing function was evaluated in all subjects by videofluoroscopic swallowing study. Brain lesions were classified as either supratentorial or in-fratentorial. We evaluated the following: the American Speech-Language-Hearing Association (ASHA) National Outcome Measurement System (NOMS) swallowing scale, clinical dysphagia scale, functional dysphagia scale (FDS), penetration-aspiration scale (PAS), oral transit time, pharyngeal transit time, the presence of vallecular pouch residue, pyriform sinus residue, laryngopharyngeal incoordination, premature spillage, a decreased swal-lowing reflex, pneumonia, and the feeding method at discharge.

RESULTS

The incidence of dysphagia was similar in brain tumor and stroke patients. There were no differences in the results of the various swallowing scales and other parameters between the two groups. When compared brain tumor patients with supratentorial lesions, brain tumor patients with infratentorial lesions showed higher propor-tion of dysphagia (p=0.01), residue (p<0.01), FDS (p<0.01), PAS (p<0.01), and lower ASHA NOMS (p=0.02) at initial evaluation. However, there was no significant difference for the swallowing functions between benign and malig-nant brain tumor patients.

CONCLUSION

Swallowing function of brain tumor patients was not different from that of stroke patients according to matching age, location of lesion, and functional status. Similar to the stroke patients, brain tumor patients with infratentorial lesions present poor swallowing functions. However, the type of brain tumor as malignancy does not influence swallowing functions.

Teledynamic evaluation of oropharyngeal swallowing

PURPOSE

The objective of the present investigation was to test the feasibility and clinical utility of a real-time Internet-based protocol for remote, telefluoroscopic evaluation of oropharyngeal swallowing.

METHOD

In this prospective cohort study, the authors evaluated 32 patients with a primary diagnosis of stroke or head/neck cancer. All patients participated in 2 separate fluoroscopic swallowing evaluations--one traditional on site and one telefluoroscopic off site--through the use of a telemedicine system. Agreement between sites was tested for 3 categories of variables: (a) overall severity of swallowing difficulty, (b) presence and extent of laryngeal penetration and aspiration as rated by the 8-point Penetration-Aspiration scale, and (c) treatment recommendations.

RESULTS

Results showed overall good agreement in subjective severity ratings (κ = 0.636) and in Penetration-Aspiration scale ratings (mean absolute difference = 1.1 points) between the onsite and offsite clinicians. Agreement in treatment recommendations was moderate to high, ranging from 69.3% to 100%.

CONCLUSIONS

The present study supports the feasibility and clinical utility of a telemedicine system for evaluating oropharyngeal swallowing. Given the difficulty and expertise needed to complete such evaluations, this study offers promising clinical avenues for patients in rural, remote, and underserved communities and countries where expert swallowing specialists are not available.

The utility of pitch elevation in the evaluation of oropharyngeal Dysphagia: preliminary findings

PURPOSE

To evaluate the utility of a pitch elevation task in the assessment of oropharyngeal dysphagia.

METHOD

This study was a pilot prospective cohort study including 40 consecutive patients (16 male and 24 female) who were referred by their physician for a swallowing evaluation. Patients were evaluated with a noninstrumental clinical examination and a videofluoroscopic swallow study, and participated in a pitch elevation task during videofluoroscopic image acquisition. Relationships between pitch elevation measurements (acoustic and perceptual) and swallow parameters (penetration/aspiration and residue) were investigated.

RESULTS

Results of this pilot study revealed that both maximum fundamental frequency (F(0)) and perceptual evaluation of pitch elevation independently significantly predicted Penetration-Aspiration Scale scores for thin liquid swallows (p = .01 and .03, respectively). Vocal range (average pitch to falsetto) was not sensitive in predicting likelihood of oropharyngeal dysphagia.

CONCLUSIONS

Findings indicate that reduced pitch elevation can be indicative of reduced airway protection and swallowing impairment in some dysphagia patients and may be a useful supplement to dysphagia screening and diagnosis. Further investigation is warranted to determine the optimal utility of this procedure for different diagnostic categories of patients.

Usefulness of videofluoroscopic swallow study with mixed consistency food for patients with stroke or other brain injuries

This study evaluated the feasibility of mixed consistency foods test in patients with dysphagia which developed after stroke or other brain injuries. The findings of a videofluoroscopic swallow study (VFSS) were compared using single versus mixed consistency foods. Forty-nine patients with stroke or other brain injuries who had no significant abnormal findings in the single consistency food VFSS and started regular hospital diet were recruited for this study. Twenty-five (51%) of the 49 patients showed normal findings whereas 24 (49%) patients showed abnormal findings in the mixed consistency food VFSS. Abnormal findings included posterior spillage of liquid prematurely to pyriform sinus (n = 23), laryngeal penetration (n = 6), subglottic aspiration in the oral preparatory phase of swallowing (chewing), solid components (n = 2), and significant (more than 10%) residue in valleculae or pyriform sinus (n = 2). There was an increased risk of abnormal findings in mixed consistency food VFSS such as aspiration and penetration when a patient showed delayed pharyngeal delay time in single consistency food using liquids. In conclusion, VFSS protocols using mixed consistency foods would be useful before starting regular diet for patients after stroke or other brain injuries.

Oropharyngeal dysphagia after the acute phase of stroke: predictors of aspiration

Oropharyngeal dysphagia is frequent during the acute phase of stroke, but most patients recover. Dysphagia is related to higher incidence of aspiration, pneumonia and death. Frequently neither clinical history nor neurological evaluation predicts the presence of aspiration. In 64 patients not recovered from severe stroke after the acute phase with clinically suspected oropharyngeal dysphagia we investigated: (i) the correlation between clinical manifestations and videofluoroscopic findings; (ii) predictive factors of aspiration and silent aspiration. Clinical examination showed that 44% had impaired gag reflex, 47% cough during oral feeding, and 13% changes in voice after swallowing. Videofluoroscopy revealed some abnormality in 87%: 53% in the oral phase and 84% in the pharyngeal phase (aspiration in 66%; half being silent). Impaired pharyngeal safety was more frequent in posterior territory lesions and patients with a history of pneumonia (P<0.01). No correlation was found between clinical evaluation findings and presence of aspiration. Silent aspirations were more frequent in patients with previous orotracheal intubation (P<0.05) and abnormalities in velopharyngeal reflexes (P<0.05). We concluded that in patients not recovered from severe stroke after the acute phase and with suspected oropharyngeal dysphagia, clinical evaluation is of scant use in predicting aspiration and silent aspiration. Videofluoroscopic examination is mandatory in these patients.

Lung volume effects on pharyngeal swallowing physiology

The experiment was a prospective, repeated-measures design intended to determine how the variation of lung volume affects specific measures of swallowing physiology. Swallows were recorded in 28 healthy subjects, who ranged in age from 21 to 40 yr (mean age of 29 yr), by using simultaneous videofluoroscopy, bipolar intramuscular electromyography, and respiratory inductance plethysmography. Each subject swallowed three standardized pudding-like consistency boluses at three randomized lung volumes: total lung capacity, functional residual capacity, and residual volume. The results showed that pharyngeal activity duration of deglutition for swallows produced at residual volume was significantly longer than those occurring at total lung capacity or at functional residual capacity. No significant differences were found for bolus transit time or intramuscular electromyography of the superior constrictor. The results of this experiment lend support to the hypothesis that the respiratory system may have a regulatory function related to swallowing and that positive subglottic air pressure may be important for swallowing integrity. Eventually, new treatment paradigms for oropharyngeal dysphagia that are based on respiratory physiology may be developed.