Complications and outcome after acute stroke. Does dysphagia matter?

Design and Validation of the Oropharyngeal Dysphagia Screening Test for Patients and Professionals: A Preliminary Study

Dysphagia is a very common symptom in people of advanced age and with neurological diseases, although it often remains undiagnosed. At present, there are few assessment tools adapted for the Spanish-speaking population; of the few existing, most of them follow a self-reporting format, which requires a well-preserved cognitive state in the patient in order to be tested. Therefore, the main aim of this study was to design and validate an instrument for screening dysphagia without food, which could have a quick application and did not compromise the patient's safety. A secondary aim was to study the test's ability to examine this symptom in people with cognitive disorders. The study was carried out with 206 participants divided into three groups: people with dysphagia and with preserved cognitive abilities, people with dysphagia and with altered cognitive abilities, and people without dysphagia and with preserved cognitive skills (control group). Participants were assessed with the designed Oropharyngeal Dysphagia Screening Test for Patients and Professionals and other dysphagia tests. The results revealed appropriate psychometric features: reliability and validity both for screening dysphagia directly with the patients or if the tester is the professional caregiver responsible for feeding (in cases of altered cognitive abilities). As conclusion, the Oropharyngeal Dysphagia Screening Test for Patients and Professionals is an instrument of easy use and of short duration that has shown adequate results of reliability and validity, thus being useful for the screening of dysphagia in Spanish-speaking populations.

Effects of electromyographic biofeedback as an adjunctive therapy in the treatment of swallowing disorders: a systematic review of the literature

PURPOSE

To describe the primary effects of electromyographic biofeedback therapy on swallowing via a systematic review.

METHODS

A blind search was carried out by two researchers in the PubMed and Bireme platforms and in the Medline, Lilacs, SciELO, PsycINFO, CINAHL, and Web of Science databases, and the journal articles identified therein were evaluated for inclusion in the study. Original articles associated with the theme were selected with no population-, region-, or language-associated limits. A protocol was created for this study with the following points: author, year, place, number and characteristics of participants, activities evaluated, instruments used, and main results. The PEDro scale was used to analyze the quality of the studies.

RESULTS

Among the 686 articles identified in the combined searches, 566 were duplicates. A total of 65 articles were discarded after the title and abstract were read, and a further 29 articles were discarded after the full text was read, yielding a total of six articles for inclusion. In summary, the results lead us to believe that positive effects on the laryngeal lifting capacity, improved swallowing functions, and increased excursion and maximal elevation of the hyoid bone, may be directly related to this method of therapy.

CONCLUSIONS

Adjunctive therapeutic protocols with biofeedback electromyography exert positive effects on swallowing function.

Clinical Approaches to Assess Post-extubation Dysphagia (PED) in the Critically Ill

Swallowing disorders and respective consequences (including aspiration-induced pneumonia) are often observed in extubated ICU patients with data indicating that a large number of patients are affected. We recently demonstrated in a large-scale analysis that the incidence of post-extubation dysphagia (PED) is 12.4% in a general ICU population and about 18% in emergency admissions to the ICU. Importantly, PED was mostly sustained until hospital discharge and independently predicted 28- and 90-day mortality. Although oropharyngeal/laryngeal trauma, neuromuscular ICU-acquired weakness, reduced sensation/sensorium, dyssynchronous breathing, and gastrointestinal reflux, are all considered to contribute to PED, little is known about the underlying pathomechanisms and risk factors leading to PED in critically ill patients. Systematic screening of all potential ICU patients for oropharyngeal dysphagia (OD) seems key for early recognition and follow-up, as well as the design and testing of novel therapeutic interventions. Today, screening methods and clinical investigations for dysphagia differ considerably. In the context of a recently proposed pragmatic screening algorithm introduced by us, we provide a concise review on currently available non-instrumental techniques that could potentially serve for non-instrumental OD assessment in critically ill patients. Following systematic literature review, we find that non-instrumental OD assessments were mostly tested in different patient populations with only a minority of studies performed in critically ill patients. Due to little available data on non-instrumental dysphagia assessment in the ICU, future investigations should aim to validate respective approaches in the critically ill against an instrumental (gold) standard, for example, flexible endoscopic evaluation of swallowing. An international expert panel is encouraged to addresses critical illness-related definitions, screening and confirmatory assessment approaches, treatment recommendations, and identifies optimal patient-centered outcome measures for future clinical investigations.

Experiences of living with persisting post-stroke dysphagia and of dysphagia management - a qualitative study

PURPOSE

The aim of this study was to investigate people's experiences of living with dysphagia after stroke, and their experiences of dysphagia management.

METHODS

The study design was qualitative, and an open-ended approach to data collection was used, with follow-up probing questions to gain more information as needed. Personal interviews were conducted with five persons who had persisting moderate to severe dysphagia after stroke, living in the south-west part of Sweden. The data were analysed with qualitative content analysis.

RESULTS

When analysing the data, the following theme emerged; "Dysphagia impacts life situations negatively and requires individually adapted, long term support from skilled health care professionals". The theme consists of three categories: "Learning to manage dysphagia and its complications", "Professional support with dysphagia varies" and "Finding small moments of joy despite large restrictions in life situations".

CONCLUSIONS

Findings indicated that people with dysphagia experienced a lack of support from health care professionals. Better health care support following discharge from hospital is required to ensure an optimal quality of life. Actions to achieve this may include developing national guidelines for adequate dysphagia follow-up and establishing multidisciplinary dysphagia teams in hospitals and long-term care facilities.

Clinical Importance of Peak Cough Flow in Dysphagia Evaluation of Patients Diagnosed With Ischemic Stroke

Objective

To investigate the relationship between peak cough flow (PCF), pulmonary function tests (PFT), and severity of dysphagia in patients with ischemic stroke.

Methods

This study included patients diagnosed with ischemic stroke, who underwent videofluoroscopic swallowing study (VFSS), PCF and PFT from March 2016 to February 2017. The dysphagia severity was assessed using the videofluoroscopic dysphagia scale (VDS). Correlation analysis of VDS, PFT and PCF was performed. Patients were divided into three groups based on VDS score. One-way ANOVA of VDS was performed to analyze PCF, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and age among the different groups.

Results

The correlation coefficients of VDS and PCF, VDS and FVC, and VDS and FEV1 were -0.836, -0.508, and -0.430, respectively, all of which were statistically significant at the level of p<0.001. The one-way ANOVA indicated statistically significant differences in PCF, FVC, FEV1, and age among the VDS groups. Statistically significant differences in VDS and age were observed between aspiration pneumoia and non-aspiration pneumonia groups.

Conclusion

Coughing is a useful factor in evaluating the risk of aspiration in dysphagia patients. Evaluation of respiratory and coughing function should be conducted during the swallowing assessment of patients with ischemic stroke.

A Novel Approach for Swallow Detection by Fusing Throat Acceleration and PPG Signal

Swallow, as one of the most complex somatic reflexes, is a mirror of our daily ingestion and physical health. In recent years, accelerometry has become a simple and popular tool for non-invasive swallow detection. However, very few physiological signals are used in this field. In this paper, we first notice that swallowing causes significant throat photoplethysmogram (PPG) waveform fluctuation. With this inspiration, we present a novel approach for swallow detection by fusing throat acceleration (ACC) and PPG signal. The support vector machine (SVM) classifier is employed and a score level fusion method is used to access and fuse the information from ACC and PPG signal. The fusion result achieves 90.5{\% precision as well as 60.0{\% specificity, higher than the PPG based detection and the ACC based detection. The experiment result shows that our method combines the characteristics of ACC and PPG signal, providing better overall performance in swallow detection.

Swallowing therapy for dysphagia in acute and subacute stroke

BACKGROUND

Dysphagia (swallowing problems), which is common after stroke, is associated with increased risk of death or dependency, occurrence of pneumonia, poor quality of life, and longer hospital stay. Treatments provided to improve dysphagia are aimed at accelerating recovery of swallowing function and reducing these risks. This is an update of the review first published in 1999 and updated in 2012.

OBJECTIVES

To assess the effects of swallowing therapy on death or dependency among stroke survivors with dysphagia within six months of stroke onset.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (26 June 2018), the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 6) in the Cochrane Library (searched 26 June 2018), MEDLINE (26 June 2018), Embase (26 June 2018), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (26 June 2018), Web of Science Core Collection (26 June 2018), SpeechBITE (28 June 2016), ClinicalTrials.Gov (26 June 2018), and the World Health Organization International Clinical Trials Registry Platform (26 June 2018). We also searched Google Scholar (7 June 2018) and the reference lists of relevant trials and review articles.

SELECTION CRITERIA

We sought to include randomised controlled trials (RCTs) of interventions for people with dysphagia and recent stroke (within six months).

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the inclusion criteria, extracted data, assessed risk of bias, used the GRADE approach to assess the quality of evidence, and resolved disagreements through discussion with the third review author (PB). We used random-effects models to calculate odds ratios (ORs), mean differences (MDs), and standardised mean differences (SMDs), and provided 95% confidence intervals (CIs) for each.The primary outcome was functional outcome, defined as death or dependency (or death or disability), at the end of the trial. Secondary outcomes were case fatality at the end of the trial, length of inpatient stay, proportion of participants with dysphagia at the end of the trial, swallowing ability, penetration aspiration score, or pneumonia, pharyngeal transit time, institutionalisation, and nutrition.

MAIN RESULTS

We added 27 new studies (1777 participants) to this update to include a total of 41 trials (2660 participants).We assessed the efficacy of swallowing therapy overall and in subgroups by type of intervention: acupuncture (11 studies), behavioural interventions (nine studies), drug therapy (three studies), neuromuscular electrical stimulation (NMES; six studies), pharyngeal electrical stimulation (PES; four studies), physical stimulation (three studies), transcranial direct current stimulation (tDCS; two studies), and transcranial magnetic stimulation (TMS; nine studies).Swallowing therapy had no effect on the primary outcome (death or dependency/disability at the end of the trial) based on data from one trial (two data sets) (OR 1.05, 95% CI 0.63 to 1.75; 306 participants; 2 studies; I² = 0%; P = 0.86; moderate-quality evidence). Swallowing therapy had no effect on case fatality at the end of the trial (OR 1.00, 95% CI 0.66 to 1.52; 766 participants; 14 studies; I² = 6%; P = 0.99; moderate-quality evidence). Swallowing therapy probably reduced length of inpatient stay (MD -2.9, 95% CI -5.65 to -0.15; 577 participants; 8 studies; I² = 11%; P = 0.04; moderate-quality evidence). Researchers found no evidence of a subgroup effect based on testing for subgroup differences (P = 0.54). Swallowing therapy may have reduced the proportion of participants with dysphagia at the end of the trial (OR 0.42, 95% CI 0.32 to 0.55; 1487 participants; 23 studies; I² = 0%; P = 0.00001; low-quality evidence). Trial results show no evidence of a subgroup effect based on testing for subgroup differences (P = 0.91). Swallowing therapy may improve swallowing ability (SMD -0.66, 95% CI -1.01 to -0.32; 1173 participants; 26 studies; I² = 86%; P = 0.0002; very low-quality evidence). We found no evidence of a subgroup effect based on testing for subgroup differences (P = 0.09). We noted moderate to substantial heterogeneity between trials for these interventions. Swallowing therapy did not reduce the penetration aspiration score (i.e. it did not reduce radiological aspiration) (SMD -0.37, 95% CI -0.74 to -0.00; 303 participants; 11 studies; I² = 46%; P = 0.05; low-quality evidence). Swallowing therapy may reduce the incidence of chest infection or pneumonia (OR 0.36, 95% CI 0.16 to 0.78; 618 participants; 9 studies; I² = 59%; P = 0.009; very low-quality evidence).

AUTHORS' CONCLUSIONS

Moderate- and low-quality evidence suggests that swallowing therapy did not have a significant effect on the outcomes of death or dependency/disability, case fatality at the end of the trial, or penetration aspiration score. However, swallowing therapy may have reduced length of hospital stay, dysphagia, and chest infections, and may have improved swallowing ability. However, these results are based on evidence of variable quality, involving a variety of interventions. Further high-quality trials are needed to test whether specific interventions are effective.

Diagnostic validity of methods for assessment of swallowing sounds: a systematic review

Introduction

Objective

Methods

Results

Conclusion

Determination of the cut-off point of the Functional Independence Measure as a predictor of adverse events in patients with acute stroke

Objective

This study was performed to determine the cut-off point of the Functional Independence Measure (FIM) to discriminate patients with acute stroke who develop adverse events during their stay in a stroke care unit (SCU).

Methods

All consecutive patients with stroke admitted to a single institute from January to March 2015 were enrolled. They were divided into two groups according to their average daily energy intake in the SCU: ≥66% or <66% of the target (high- and low-energy group, respectively). A receiver operating characteristic curve was used to determine the cut-off point of the FIM to predict adverse events in patients with acute stroke.

Results

The length of stay in the SCU was significantly longer and the serum C-reactive protein level (CRP) was significantly higher in the low- than high-energy group (7 vs. 4 days and 2.15 vs. 0.20 mg/dL, respectively). The total FIM score cut-off value was 63 points.

Conclusions

An energy intake of <66% of the target was associated with a significantly longer stay in the SCU and a higher CRP level. A total FIM score cut-off value of 63 points is useful to discriminate patients with adverse events among those with acute stroke.

Impact of oropharyngeal dysphagia on healthcare cost and length of stay in hospital: a systematic review

BACKGROUND

Healthcare systems internationally are under an ever-increasing demand for services that must be delivered in an efficient, effective and affordable manner. Several patient-related and organisational factors influence health-care expenditure and utilisation, including oropharyngeal dysphagia. Here, we present a systematic review of the literature and meta-analyses investigating how oropharyngeal dysphagia influences healthcare utilisation through length of stay (LOS) and cost.

METHODS

Using a standardised approach, eight databases were systematically searched for relevant articles reporting on oropharyngeal dysphagia attributable inpatient LOS and healthcare costs through June 2016. Study methodologies were critically appraised and where appropriate, extracted LOS data were analysed in an overall summary statistic.

RESULTS

Eleven studies reported on cost data, and 23 studies were included reporting on LOS data. Descriptively, the presence of dysphagia added 40.36% to health care costs across studies. Meta-analysis of all-cause admission data from 13 cohort studies revealed an increased LOS of 2.99 days (95% CI, 2.7, 3.3). A subgroup analysis revealed that admission for stroke resulted in higher and more variable LOS of 4.73 days (95% CI, 2.7, 7.2). Presence of dysphagia across all causes was also statistically significantly different regardless of geographical location: Europe (8.42 days; 95% CI, 4.3; 12.5), North America (3.91 days; 95% CI, 3.3, 4.5). No studies included in meta-analysis were conducted in Asia.

CONCLUSIONS

This systematic review demonstrated that the presence of oropharyngeal dysphagia significantly increases healthcare utilisation and cost, highlighting the need to recognise oropharyngeal dysphagia as an important contributor to pressure on healthcare systems.

Dual Transcranial Direct Current Stimulation for Poststroke Dysphagia: A Randomized Controlled Trial

BACKGROUND

Poststroke dysphagia is associated with considerable morbidity and has high health care cost implications.

OBJECTIVE

To evaluate whether anodal transcranial direct current stimulation (tDCS) over the lesioned hemisphere and cathodal tDCS to the contralateral one during the early stage of rehabilitation can improve poststroke dysphagia.

METHODS

A total of 40 patients referred to our neurorehabilitation department were randomized to receive anodal tDCS over the damaged hemisphere plus cathodal stimulation over the contralateral one versus sham stimulation during swallowing maneuvers over the course of 10 sessions of treatment. Swallowing function was evaluated before and after stimulation using the Dysphagia Outcome and Severity Scale (DOSS).

RESULTS

The percentage of patients who reached various thresholds of improvement was higher in the tDCS group than in the sham group, but the differences were not significant (eg, DOSS score ≥ 20% increase from baseline: 55% in the tDCS group vs 40% in the sham group; P = .53). Among all variables recorded at baseline, only a subgroup of patients without nasogastric tube showed a significantly higher improvement with tDCS treatment versus sham (DOSS score ≥10% and ≥20% from baseline: 64.29% vs 0%, P = .01).

CONCLUSIONS

In patients with poststroke dysphagia, treatment with dual tDCS in the early phase of rehabilitation does not significantly increase the probability of recovery compared with sham stimulation.

Dysphagia and its effects on swallowing sounds and vibrations in adults

BACKGROUND

To utilize cervical auscultation as a means of screening for risk of dysphagia, we must first determine how the signal differs between healthy subjects and subjects with swallowing disorders.

METHODS

In this experiment we gathered swallowing sound and vibration data from 53 (13 with stroke, 40 without) patients referred for imaging evaluation of swallowing function with videofluoroscopy. The analysis was limited to non-aspirating swallows of liquid with either thin (< 5 cps) or viscous ([Formula: see text]) consistency. After calculating a selection of generalized time, frequency, and time frequency features for each swallow, we compared our data against our findings in a previous experiment that investigated identical features for a different group of 56 healthy subjects.

RESULTS

We found that nearly all of our chosen features for both vibrations and sounds showed significant differences between the healthy and disordered swallows despite the absence of aspiration. We also found only negligible differences between dysphagia as a symptom of stroke and dysphagia as a symptom of another condition.

CONCLUSION

Non-aspirating swallows from healthy controls and patients with dysphagia have distinct feature patterns. These findings should greatly help the development of the cervical auscultation field and serve as a reference for future investigations into more specialized characterization methods.

Deep Learning for Classification of Normal Swallows in Adults

Cervical auscultation is a method for assessing swallowing performance. However, its ability to serve as a classification tool for a practical clinical assessment method is not fully understood. In this study, we utilized neural network classification methods in the form of Deep Belief networks in order to classify swallows. We specifically utilized swallows that did not result in clinically significant aspiration and classified them on whether they originated from healthy subjects or unhealthy patients. Dual-axis swallowing vibrations from 1946 discrete swallows were recorded from 55 healthy and 53 unhealthy subjects. The Fourier transforms of both signals were used as inputs to the networks of various sizes. We found that single and multi-layer Deep Belief networks perform nearly identically when analyzing only a single vibration signal. However, multi-layered Deep Belief networks demonstrated approximately a 5% to 10% greater accuracy and sensitivity when both signals were analyzed concurrently, indicating that higher-order relationships between these vibrations are important for classification and assessment.

Route of Feeding as a Proxy for Dysphagia After Stroke and the Effect of Transdermal Glyceryl Trinitrate: Data from the Efficacy of Nitric Oxide in Stroke Randomised Controlled Trial

Post-stroke dysphagia is common, associated with poor outcome and often requires non-oral feeding/fluids. The relationship between route of feeding and outcome, as well as treatment with glyceryl trinitrate (GTN), was studied prospectively. The Efficacy of Nitric Oxide in Stroke (ENOS) trial assessed transdermal GTN (5 mg versus none for 7 days) in 4011 patients with acute stroke and high blood pressure. Feeding route (oral = normal or soft diet; non-oral = nasogastric tube, percutaneous endoscopic gastrostomy tube, parenteral fluids, no fluids) was assessed at baseline and day 7. The primary outcome was the modified Rankin Scale (mRS) measured at day 90. At baseline, 1331 (33.2%) patients had non-oral feeding, were older, had more severe stroke and more were female, than 2680 (66.8%) patients with oral feeding. By day 7, 756 patients had improved from non-oral to oral feeding, and 119 had deteriorated. Non-oral feeding at baseline was associated with more impairment at day 7 (Scandinavian Stroke Scale 29.0 versus 43.7; 2p < 0.001), and worse mRS (4.0 versus 2.7; 2p < 0.001) and death (23.6 versus 6.8%; 2p = 0.014) at day 90. Although GTN did not modify route of feeding overall, randomisation ≤6 h of stroke was associated with a move to more oral feeding at day 7 (odds ratio = 0.61, 95% confidence intervals 0.38, 0.98; 2p = 0.040). As a proxy for dysphagia, non-oral feeding is present in 33% of patients with acute stroke and associated with more impairment, dependency and death. GTN moved feeding route towards oral intake if given very early after stroke. Clinical Trial Registration Clinical Trial Registration-URL: http://www.controlled-trials.com . Unique identifier: ISRCTN99414122.

Prevalence, risk factors and complications of oropharyngeal dysphagia in stroke patients: A cohort study

BACKGROUND

Oropharyngeal dysphagia (OD) is a prevalent poststroke condition with severe complications and increased mortality. Poststroke OD prevalence varies among studies and there is little evidence of its related risk factors and associated complications.

OBJECTIVE

to evaluate the prevalence of OD after stroke and the risk factors and associated complications.

METHODS

We performed a prospective longitudinal study of stroke patients consecutively admitted to a general hospital. OD was diagnosed with the volume-viscosity swallow test (V-VST). Demographic, functional status and topographical and clinical variables of stroke were collected to assess risk factors for OD. We evaluated functional status, mortality, respiratory infections, and readmissions 3 and 12 months after stroke. A multivariate regression analysis determined associated risk factors for OD and for each outcome variable.

KEY RESULTS

We included 395 stroke patients with a 45.06% prevalence of OD on admission. OD was independently associated with age (OR = 1.05; CI = 1.02-1.08), previous stroke (OR = 2.40; CI = 1.00-5.79), severity using the National Institute of Health Stroke Scale (OR = 3.52; CI = 1.57-7.87) and volume of the lesion (OR = 1.02; CI = 1.01-1.03). OD after stroke was an independent risk factor for prolonged hospital stay (P = .049; β = 0.938) and institutionalization after discharge (OR = 0.47; CI = 0.24-0.92); OD was an independent risk factor for poorer functional capacity (OR = 3.00; CI = 1.58-5.68) and increased mortality (HR = 6.90; CI = 1.57-30.34) 3 months after stroke.

CONCLUSIONS & INFERENCES

Poststroke OD is prevalent and associated with poor short and long term prognosis. Stroke severity and patient status before stroke were more relevant to OD than lesion location. Systematic screening programs and early OD management could significantly improve poststroke patient outcome.

The Effect of Improved Dysphagia Care on Outcome in Patients with Acute Stroke: Trends from 8-Year Data of a Large Stroke Register

BACKGROUND

Early dysphagia screening and appropriate management are recommended by current guidelines to reduce complications and case fatality in acute stroke. However, data on the potential benefit of changes in dysphagia care on patient outcome are limited. Our objective was to assess the degree of implementation of dysphagia guidelines and determine the impact of modifications in dysphagia screening and treatment practices on disease complications and outcome in stroke patients over time.

METHODS

In this prospective register-based study ("Stroke Register of Northwestern Germany"), all adult stroke patients admitted to 157 participating hospitals between January, 2008 and December, 2015 were included (n = 674,423). Dysphagia incidence upon admission, the proportion of patients receiving a standardized swallowing screening, and the percentage of dysphagic patients being referred to a speech language therapist (SLT) for treatment were obtained per year. Pneumonia rate, modified Rankin Scale (mRS) at discharge, and in-hospital mortality were compared between groups of dysphagic vs. non-dysphagic patients over time.

RESULTS

Screening proportions continuously increased from 47.2% in 2008 to 86.6% in 2015. But the proportion diagnosed with dysphagia remained stable with about 19%. The number of dysphagic patients receiving SLT treatment grew from 81.6 up to 87.0%. Pneumonia incidence was higher in dysphagic stroke cases (adjusted OR 5.4 [5.2-5.5], p < 0.001), accompanied by a worse mRS at discharge (adjusted OR for mRS ≥3: 3.1 [3.0-3.1], p < 0.001) and higher mortality (adjusted OR 3.1 [3.0-3.2], p < 0.001). The order of magnitude of these end points did not change over time.

CONCLUSION

Although advances have been made in dysphagia care, prevalent screening and treatment practices remain insufficient to reduce pneumonia rate, improve functional outcome, and decrease case fatality in dysphagic stroke patients. More research is urgently needed to develop more effective swallowing therapies.

Influence of attention and bolus volume on brain organization during swallowing

It has been shown that swallowing involves certain attentional and cognitive resources which, when disrupted can influence swallowing function with in dysphagic patient. However, there are still open questions regarding the influence of attention and cognitive demands on brain activity during swallowing. In order to understand how brain regions responsible for attention influence brain activity during swallowing, we compared brain organization during no-distraction swallowing and swallowing with distraction. Fifteen healthy male adults participated in the data collection process. Participants performed ten 1 ml, ten 5 ml, and ten 10 ml water swallows under both no-distraction conditions and during distraction while EEG signals were recorded. After standard pre-processing of the EEG signals, brain networks were formed using the time-frequency based synchrony measure. The brain networks formed were then compared between the two sets of conditions. Results showed that there are differences in the Delta, Theta, Alpha, Beta, and Gamma frequency bands between no-distraction swallowing and swallowing with distraction. Differences in the Delta and Theta frequency bands can be attributed to changes in subliminal processes, while changes in the Alpha and Beta frequency bands are directly associated with the various levels of attention and cognitive demands during swallowing process, and changes in the Gamma frequency band are due to changes in motor activity. Furthermore, we showed that variations in bolus volume influenced the swallowing brain networks in the Delta, Theta, Alpha, Beta, and Gamma frequency bands. Changes in the Delta, Theta, and Alpha frequency bands are due to sensory perturbations evoked by the various bolus volumes. Changes in the Beta frequency band are due to reallocation of cognitive demands, while changes in the Gamma frequency band are due to changes in motor activity produced by variations in bolus volume. These findings could potentially lead to the development of better understanding of the nature of dysphagia and various rehabilitation strategies for patients with neurogenic dysphagia who have altered attention or impaired cognitive functions.

Screening for Dysphagia in Adult Patients with Stroke: Assessing the Accuracy of Informal Detection

Early identification of dysphagia by screening is recommended best practice for patients admitted to hospital with acute stroke. Screening can reduce the risk of pneumonia and promote stroke recovery, yet some institutions do not utilize a formal screening protocol. This study assessed the accuracy of informal dysphagia detection prior to implementation of a formal screening protocol. We conducted a secondary analysis of data captured between 2003 and 2008 from a sample of 250 adult stroke survivors admitted to a tertiary care centre. Using a priori criteria, patient medical records were reviewed for notation about dysphagia; if present, the date/time of notation, writer's profession, and suggestion of dysphagia presence. To assess accuracy of notations indicating dysphagia presence, we used speech language pathology (SLP) assessments as the criterion reference. There were 221 patient medical records available for review. Patients were male (56%), averaged 68 years (SD = 15.0), with a mean Canadian Neurological Scale score of 8.1 (SD = 3.0). First notations of swallowing by SLP were excluded. Of the remaining 170 patients, 147 (87%) had first notations (104 by nurses; 40 by physicians) within a median of 24.3 h from admission. Accuracy of detecting dysphagia from informal notations was low, with a sensitivity of 36.7% [95% CI, 24.9, 50.1], but specificity was high (94.2% [95% CI, 86.5, 97.9]). Informal identification methods, although timely, are suboptimal in their accuracy to detect dysphagia and leave patients with stroke at risk for poor health outcomes. Given these findings, we encourage the use of psychometrically validated formal screening protocols to identify dysphagia.

Risk factors for laryngeal penetration-aspiration in patients with acute traumatic cervical spinal cord injury

BACKGROUND CONTEXT

Laryngeal penetration-aspiration, the entry of material into the airways, is considered the most severe subtype of dysphagia and is common among patients with acute cervical spinal cord injury (SCI).

PURPOSE

The aim of this study was to investigate risk factors for penetration-aspiration in patients with acute traumatic cervical spinal cord injury (TCSCI).

STUDY DESIGN

This is a prospective cohort study.

PATIENT SAMPLE

Thirty-seven patients with TCSCI were included in the study.

OUTCOME MEASURES

The highest Rosenbek penetration-aspiration scale (PAS; range 1-8) score of each patient was the primary outcome measure. The risk factors consisted of patient characteristics, demographics, and clinical signs observed during a clinical swallowing trial.

MATERIALS AND METHODS

A clinical swallowing trial and videofluoroscopic swallowing study (VFSS) was performed on all patients within 28 days post injury. For group comparisons, the patients were divided into two groups: (1) penetrator-aspirators (PAS score ≥3) and (2) non-penetrator-aspirators (PAS score ≤2).

RESULTS

Of the 37 patients, 83.8% were male. The mean age at the time of the injury was 61.2 years. Most patients had an incomplete TCSCI (78.4%) caused by a fall (75.7%). In the VFSS, 51.4% of the patients were penetrator-aspirators, and 71.4% had silent aspiration. The risk factors for predicting penetration-aspiration were (1) necessity of bronchoscopies, (2) lower level of anterior cervical operation, (3) coughing, throat clearing, choking related to swallowing, and (4) changes in voice quality related to swallowing. Binary logistic regression identified coughing, throat clearing, choking, and changes in voice quality related to swallowing as independent risk factors for penetration-aspiration.

CONCLUSIONS

The necessity of bronchoscopies, postinjury lower cervical spine anterior surgery, coughing, throat clearing, choking, and changes in voice quality related to swallowing was a markedrisk factor for aspiration and penetration following a cervical SCI. These factors and signs should be used to suspect injury-related pharyngeal dysfunction and to initiate preventive measures to avoid complications. The clinical swallowing evaluation is a relevant adjunct in the management of these patients and can improve the detection of penetration and aspiration.

Dysphagia in Mechanically Ventilated ICU Patients (DYnAMICS): A Prospective Observational Trial

OBJECTIVES

Swallowing disorders may be associated with adverse clinical outcomes in patients following invasive mechanical ventilation. We investigated the incidence of dysphagia, its time course, and association with clinically relevant outcomes in extubated critically ill patients.

DESIGN

Prospective observational trial with systematic dysphagia screening and follow-up until 90 days or death.

SETTINGS

ICU of a tertiary care academic center.

PATIENTS

One thousand three-hundred four admissions of mixed adult ICU patients (median age, 66.0 yr [interquartile range, 54.0-74.0]; Acute Physiology and Chronic Health Evaluation-II score, 19.0 [interquartile range, 14.0-24.0]) were screened for postextubation dysphagia. Primary ICU admissions (n = 933) were analyzed and followed up until 90 days or death. Patients from an independent academic center served as confirmatory cohort (n = 220).

INTERVENTIONS

Bedside screening for dysphagia was performed within 3 hours after extubation by trained ICU nurses. Positive screening triggered confirmatory specialist bedside swallowing examinations and follow-up until hospital discharge.

MEASUREMENTS AND MAIN RESULTS

Dysphagia screening was positive in 12.4% (n = 116/933) after extubation (18.3% of emergency and 4.9% of elective patients) and confirmed by specialists within 24 hours from positive screening in 87.3% (n = 96/110, n = 6 missing data). The dysphagia incidence at ICU discharge was 10.3% (n = 96/933) of which 60.4% (n = 58/96) remained positive until hospital discharge. Days on feeding tube, length of mechanical ventilation and ICU/hospital stay, and hospital mortality were higher in patients with dysphagia (all p < 0.001). The univariate hazard ratio for 90-day mortality for dysphagia was 3.74 (95% CI, 2.01-6.95; p < 0.001). After adjustment for disease severity and length of mechanical ventilation, dysphagia remained an independent predictor for 28-day and 90-day mortality (excess 90-d mortality 9.2%).

CONCLUSIONS

Dysphagia after extubation was common in ICU patients, sustained until hospital discharge in the majority of affected patients, and was an independent predictor of death. Dysphagia after mechanical ventilation may be an overlooked problem. Studies on underlying causes and therapeutic interventions seem warranted.

Management of swallowing in thrombolysed stroke patients: Implementation of a new protocol

PURPOSE

There is a paucity of evidence regarding dysphagia management post-thrombolysis. The aim of this case-control study was to evaluate the impact of a dysphagia management protocol on patient outcomes. Thrombolysis has been completed at our metropolitan hospital since 2011 and a dysphagia management protocol was developed in 2012.

METHOD

Chart auditing was completed for 83 participants in three groups: pre-protocol (n = 12) (2011), post-protocol (n = 28) (2012-2014), and non-thrombolysed stroke patients (n = 43).

RESULT

Following the implementation of this clinical protocol, the average time patient remained nil by mouth reduced by 9.5 h, the percentage of patients who were malnourished or at risk reduced by 24% and the number of patients who developed aspiration pneumonia reduced by 11%. The cost of hospital stay reduced by $1505. Service compliance with best practice in dysphagia management in thrombolysed patients increased from 67% to 96% in the thrombolysed patient groups.

CONCLUSION

The outcomes suggest that a clinical protocol for dysphagia management in thrombolysed patients has the potential to improve service outcomes, reduce complications from dysphagia, have financial benefits for the hospital and increase service compliance. Furthermore, the results lend support for speech pathology services to manage dysphagia on weekends.

A hybrid classifier based on nonlinear-PCA and deep belief networks with applications in dysphagia diagnosis

Traditional dysphagia prescreening diagnostic methods require doctors specialists to give patients a total score based on a water swallow test scale. This method is limited by the high dimensionality of the diagnostic elements in the water swallow test scale with heavy workload (Towards each patient, the scale requires the doctors give score for 18 diagnostic elements respectively) as well as the difficulties of extracting and using the diagnostic scale data's non-linear features and hidden expertise information (Even with the scale scores, specific diagnostic conclusions are still given by expert doctors under the expertise). In this paper, a hybrid classifier model based on Nonlinear-Principal Component Analysis (NPCA) and Deep Belief Networks (DBN) is proposed in order to effectively extract the diagnostic scale data's nonlinear features and hidden information and to provide the key scale elements' locating methods towards the diagnostic results (The key scale elements that affect different diagnostic conclusions are given to improve the efficiency and pertinence of diagnosis and reduce the workload of diagnosis). We demonstrate the effectiveness of the proposed method using the frame of 'information entropy theory'. Real dysphagia diagnosis examples from the China-Japanese Friendship Hospital are used to demonstrate applications of the proposed methods. The examples show satisfactory results compared to the traditional classifier.

Changes of cortical activation in swallowing following high frequency repetitive transcranial magnetic stimulation in older adults

BACKGROUND

This study explored whether high-frequency repetitive transcranial magnetic stimulation (rTMS) can induce positive changes in the cortical areas of older adults who do not have functional difficulties in swallowing.

METHODS

Ten healthy, right-handed, elderly volunteers were subjected to 18F-labeled fluorodeoxyglucose positron emission tomography(FDG-PET) scans when at rest, swallowing before rTMS, and swallowing after rTMS. During the swallowing study, water was infused orally via a catheter at a rate of 600 mL/h. Subjects swallowed water every 20 seconds following a light flash for 30 minutes. During rest, the light source was active, but subjects were requested not to swallow. The rTMS consisted of 5 Hz applied to a pharyngeal motor hot spot in the right hemisphere for 10 minutes every weekday for 2 weeks. The intensity of the stimulation was set at 90% of the thenar motor threshold of the same hemisphere. The differences between each patient's active image and the control images (P<.05) on a voxel-by-voxel basis were examined to find significant increases in metabolism using statistical parametric mapping software.

KEY RESULTS

The cortical areas activated by swallowing before rTMS included the bilateral sensorimotor cortex (Brodmann's areas 3 and 4) and showed symmetry. The cortical areas activated by swallowing after rTMS were the same as the areas before rTMS. There was no statistical difference between the two swallowing activation areas.

CONCLUSIONS AND INFERENCES

Older adults displayed the symmetry of cortical control of swallowing function. High frequency rTMS did not affect the activation in the swallowing sensorimotor cortices of elderly people.

Pharyngolaryngeal Sensory Deficits in Patients with Middle Cerebral Artery Infarction: Lateralization and Relation to Overall Dysphagia Severity

Background

Dysphagia is a frequent and dangerous complication of acute stroke. Apart from a well-timed oropharyngeal muscular contraction pattern, sensory feedback is of utmost importance for safe and efficient swallowing. In the present study, we therefore analyzed the relation between pharyngolaryngeal sensory deficits and post-stroke dysphagia (PSD) severity in a cohort of acute stroke patients with middle cerebral artery (MCA) infarction.

Methods

Eighty-four first-ever MCA stroke patients (41 left, 43 right) were included in this trial. In all patients, fiberoptic endoscopic evaluation of swallowing (FEES) was performed according to a standardized protocol within 96 h after stroke onset. PSD was classified according to the 6-point fiberoptic endoscopic dysphagia severity scale. Pharyngolaryngeal sensation was semi-quantitatively evaluated by a FEES-based touch technique.

Results

PSD severity was closely related to the pharyngolaryngeal sensory deficit. With regards to lateralization of the sensory deficit, there was a slight but significant preponderance of sensory loss contralateral to the side of stroke. Apart from that, right hemispheric stroke patients were found to present with a more severe PSD.

Conclusions

This study provides evidence that an intact sensory feedback is of utmost importance to perform nonimpaired swallowing and highlights the key role of disturbed pharyngeal and laryngeal afferents in the pathophysiology of PSD.

Instrumento de rastreio para disfagia orofaríngea no Acidente Vascular Encefálico - Parte I: evidências de validade baseadas no conteúdo e nos processos de resposta

RESUMO Objetivo Este estudo tem o objetivo de identificar as evidências de validade baseadas no conteúdo e nos processos de resposta de um instrumento de Rastreamento para disfagia orofaríngea no Acidente Vascular Encefálico (RADAVE). Método Os critérios para elaborar os itens do instrumento foram baseados na revisão de literatura. Um grupo de juízes com 19 profissionais distintos e da área da saúde avaliaram a relevância e representatividade das questões e o resultado foi analisado por meio do índice de validade de conteúdo (IVC). Para evidência de validade baseada nos processos de resposta, 23 profissionais da saúde aplicaram o instrumento e analisaram as questões por meio de escala estruturada e entrevista cognitiva. Resultados O RADAVE foi estruturado para ser aplicado em duas etapas. A primeira versão foi constituída por 18 questões na etapa I e 11 questões na etapa II. Oito questões da etapa I e quatro questões da etapa II não atingiram o IVC mínimo, sendo realizadas reformulações pelos autores. A entrevista cognitiva demonstrou a necessidade de novos ajustes que resultaram na versão final com 12 questões na Etapa I e seis questões na Etapa II. Conclusão Foi possível desenvolver um instrumento de rastreamento para a disfagia no Acidente Vascular Encefálico com adequadas evidências de validade baseadas no conteúdo e nos processos de resposta. As duas evidências de validade obtidas até o momento permitiram ajustar o instrumento em relação ao seu constructo. Os próximos estudos irão analisar as demais evidências de validade e as medidas de acurácia.

Systematic Review on Acupuncture for Treatment of Dysphagia after Stroke

OBJECTIVE

To assess the therapeutic efficacy of acupuncture for dysphagia after stroke.

METHODS

Seven electronic databases were searched from their inception until 31 September 2016. All randomized controlled trials (RCTs) incorporating acupuncture or acupuncture combined with other interventions for treatment of dysphagia after stroke were enrolled. Then they were extracted and assessed by two independent evaluators. Direct comparisons were conducted in RevMan 5.3.0 software.

RESULTS

6010 patients of 71 papers were included. The pooled analysis of efficacy rate of 58 studies indicated that acupuncture group was superior to the control group with moderate heterogeneity (RR = 1.17, 95% CI: 1.13 1.21, Z = 9.08, and P < 0.00001); meta-analysis of the studies using blind method showed that the efficacy rate of acupuncture group was 3.01 times that of control group with no heterogeneity (RR = 3.01, 95% CI: 1.95 4.65, Z = 4.97, and P < 0.00001). Only 13 studies mentioned the safety evaluation.

CONCLUSION

The result showed that the acupuncture group was better than control group in terms of efficacy rate of dysphagia after stroke. And the combining result of those researches using blind method was more strong in proof. Strict evaluation standard and high-quality RCT design are necessary for further exploration.

Localization of orofacial representation in the corona radiata, internal capsule and cerebral peduncle in Macaca mulatta

Subcortical white matter injury is often accompanied by orofacial motor dysfunction, but little is known about the structural substrates accounting for these common neurological deficits. We studied the trajectory of the corticobulbar projection from the orofacial region of the primary (M1), ventrolateral (LPMCv), supplementary (M2), rostral cingulate (M3) and caudal cingulate (M4) motor regions through the corona radiata (CR), internal capsule (IC) and crus cerebri of the cerebral peduncle (ccCP). In the CR each pathway was segregated. Medial motor area fibers (M2/M3/M4) arched over the caudate and lateral motor area fibers (M1/LPMCv) curved over the putamen. At superior IC levels, the pathways were widespread, involving the anterior limb, genu and posterior limb with the M3 projection located anteriorly, followed posteriorly by projections from M2, LPMCv, M4 and M1, respectively. Inferiorly, all pathways maintained this orientation but shifted posteriorly, with adjacent fiber bundles overlapping minimally. In the ccCP, M3 fibers were located medially and M1 fibers centromedially, with M2, LPMCv, and M4 pathways overlapping in between. Finally, at inferior ccCP levels, all pathways overlapped. Following CR and superior IC lesions, the dispersed pathway distribution may correlate with acute orofacial dysfunction with spared pathways contributing to orofacial motor recovery. In contrast, the gradually commixed nature of pathway representation inferiorly may enhance fiber vulnerability and correlate with severe, prolonged deficits following lower subcortical and midbrain injury. Additionally, in humans these findings may assist in interpreting orofacial movements evoked during deep brain stimulation, and neuroimaging tractography efforts to localize descending orofacial motor pathways.

The BDNF polymorphism Val66Met may be predictive of swallowing improvement post pharyngeal electrical stimulation in dysphagic stroke patients

BACKGROUND

The aim of this study was to explore the effect of brain-derived neurotrophic factor (BDNF) polymorphism rs6265 (Val66Met) in both "natural" and treatment induced recovery of swallowing after dysphagic stroke.

METHODS

Sixteen dysphagic stroke patients that completed a single-blind randomized sham controlled trial of pharyngeal electrical stimulation (PES) within 6 weeks of their stroke (N=38), were genotyped for the BDNF SNP Val66Met (rs6265) from saliva samples. These patients received active or sham PES according to randomized allocation. PES was delivered at a set frequency (5 Hz), intensity (75% of maximal tolerated), and duration (10 minutes) once a day for three consecutive days. Clinical measurements were taken from patients at baseline, 2 weeks and 3 months post entering the study. Changes in swallowing ability based on the dysphagia severity rating scale (DSRS) were compared between active and sham groups and associated with BDNF SNP status.

KEY RESULTS

In the active stimulation group, patients with the Met BDNF allele demonstrated significantly greater improvements in DSRS at 3 months compared to patients homozygous for the Val allele (P=.009). By comparison, there were no significant associations at the 2 week stage in either the active or sham group, or at 3 month in the sham group. Functional scores including the Barthel Index and modified Rankin scale were also unaffected by BDNF status.

CONCLUSIONS & INFERENCES

Our findings suggest an association between BDNF and stimulation induced swallowing recovery. Further work will be required to validate these observations and demonstrate clinical utility in patients.

Traumatic cervical spinal cord injury: a prospective clinical study of laryngeal penetration and aspiration

STUDY DESIGN

Prospective cohort study.

OBJECTIVES

Dysphagia is a relatively common secondary complication in patients with traumatic cervical spinal cord injuries (TCSCI). The purpose of this study was to determine the incidence of aspiration and penetration in patients with acute TCSCI.

SETTING

Tampere University Hospital, Tampere, Finland.

METHODS

A total of 46 patients with TCSCI were evaluated with a videofluoroscopic swallowing study (VFSS). Rosenbek's penetration-aspiration scale (PAS) was used to classify the degree of penetration or aspiration. The medical records of each patient were systematically reviewed.

RESULTS

Of the 46 patients, 85% were male. The mean age at the time of the injury was 62.1 years. Most patients had an incomplete injury (78%), and most of them due to a fall (78%). In the VFSS 19 (41%) patients penetrated and 15 (33%) aspirated. Only 12 (26%) of the patients had a PAS score of 1 indicating that swallowed material did not enter the airway. Of the patients who aspirated, 73% had silent aspiration.

CONCLUSION

The incidence of penetration or aspiration according to VFSS is high in this cohort of patients with TCSCI. Therefore, the swallowing function of patients with acute TCSCI should be routinely evaluated before initiating oral feeding. VFSS is highly recommended, particularly to rule out the possibility of silent aspiration and to achieve information on safe nutrition consistency.

Screening for aspiration risk associated with dysphagia in acute stroke

This is a protocol for a Cochrane Review (Diagnostic test accuracy). The objectives are as follows:

To determine the diagnostic accuracy of bedside screening tools for detecting dysphagia, which is a predictor of aspiration, in people with acute stroke.

To assess the influence of the following potential sources of heterogeneity.

Patient demographics (e.g. age, gender, percentage of males in study, median age of study by gender). The time post‐stroke that the study was conducted (from admission to 48 hours) to ensure only hyperacute and acute stroke dysphagia screening tools are identified. Any significant change in the participant's condition between the index and reference tests being performed. The definition of dysphagia used by the study. Level of training of nursing staff, both grade and training in the screening tool. Low‐quality studies identified from the methodological quality checklist. Type of the index test and the threshold of the index test. Type of the reference test.

Pharyngeal Swallowing Mechanics Secondary to Hemispheric Stroke

BACKGROUND

Computational analysis of swallowing mechanics (CASM) is a method that utilizes multivariate shape change analysis to uncover covariant elements of pharyngeal swallowing mechanics associated with impairment using videofluoroscopic swallowing studies. The goals of this preliminary study were to (1) characterize swallowing mechanics underlying stroke-related dysphagia, (2) decipher the impact of left and right hemispheric strokes on pharyngeal swallowing mechanics, and (3) determine pharyngeal swallowing mechanics associated with penetration-aspiration status.

METHODS

Videofluoroscopic swallowing studies of 18 dysphagic patients with hemispheric infarcts and age- and gender-matched controls were selected from well-controlled data sets. Patient data including laterality and penetration-aspiration status were collected. Coordinates mapping muscle group action during swallowing were collected from videos. Multivariate morphometric analyses of coordinates associated with stroke, affected hemisphere, and penetration-aspiration status were performed.

RESULTS

Pharyngeal swallowing mechanics differed significantly in the following comparisons: stroke versus controls (D = 2.19, P < .0001), right hemispheric stroke versus controls (D = 3.64, P < .0001), left hemispheric stroke versus controls (D = 2.06, P < .0001), right hemispheric stroke versus left hemispheric stroke (D = 2.89, P < .0001), and penetration-aspiration versus within normal limits (D = 2.25, P < .0001). Differences in pharyngeal swallowing mechanics associated with each comparison were visualized using eigenvectors.

CONCLUSIONS

Whereas current literature focuses on timing changes in stroke-related dysphagia, these data suggest that mechanical changes are also functionally important. Pharyngeal swallowing mechanics differed by the affected hemisphere and the penetration-aspiration status. CASM can be used to identify patient-specific swallowing impairment associated with stroke injury that could help guide rehabilitation strategies to improve swallowing outcomes.

Lesion Characteristics of Chronic Dysphagia in Patients With Supratentorial Stroke

Objective

To analyze the relationship between brain lesion location and type of chronic dysphagia in patients with supratentorial stroke.

Methods

Data from 82 chronic stroke patients who underwent videofluoroscopic swallowing studies at >6 months after an initial stroke event were retrospectively analyzed. Delayed oral transit time, delayed pharyngeal transit time, and the presence of aspiration were extracted. A voxel-based lesion symptom mapping (VLSM) analysis was used to correlate types of dysphagia with specific brain lesions.

Results

VLSM identified several clusters of voxels that significantly correlated with type of dysphagia. Delayed oral transit time mainly correlated with lesions in the left inferior frontal lobe and precentral gyrus; delayed pharyngeal time mainly correlated with lesions in the right basal ganglia and corona radiate; and aspiration was mainly correlated with lesions in the putamen.

Conclusion

Understanding the association between lesion location and dysphagia in chronic stroke patients is an important first step towards predicting permanent dysphagia after stroke. Improved understanding of the neural correlates of dysphagia will inform the utility of interventions for its treatment and prevention after stroke.

Effects of expiratory muscle strength training on swallowing function in acute stroke patients with dysphagia

[Purpose] This study was conducted to identify the effects of expiratory muscle strength training on swallowing function in acute stroke patients with dysphagia. [Subjects and Methods] A total of 18 stroke patients with dysphagia were enrolled in the study. All participants were randomly assigned to either an experimental group (n=9) or a control group (n=9). All participants performed traditional-swallowing rehabilitation therapy in 30-minute sessions five times a week for four weeks; however, only the experimental group received expiratory muscle strength training. [Results] Both groups showed significant improvements after mediation. When compared with the control group, the functional dysphagia scale, vallecular residue, and penetration-aspiration scale were significantly improved in the experimental group. [Conclusion] Expiratory muscle strength training is an effective intervention for impaired swallowing function in acute strike patients with dysphagia.