Prevalence and evaluation of oropharyngeal dysphagia in patients with severe acute respiratory syndrome coronavirus 2 infection in the intensive care unit.

OBJECTIVE: The main objective was to assess the prevalence of dysphagia in the intensive care unit in patients with coronavirus disease 2019.Methods. A cohort, observational, retrospective study was conducted of patients admitted to the intensive care unit for severe acute respiratory syndrome coronavirus 2 pneumonia at the University Hospital of Rouen in France. RESULTS: Over 4 months, 58 patients were intubated and ventilated, 43 of whom were evaluated. Screening revealed post-extubation dysphagia in 62.7 per cent of patients. In univariate analysis, a significant association was found between the presence of dysphagia and: the severity of the initial pathology, the duration of intubation, the duration of curare use, the degree of muscle weakness and the severity indicated on the initial scan. At the end of intensive care unit treatment, 22 per cent of the dysphagic patients had a normal diet, 56 per cent had an adapted diet and 22 per cent still received exclusive tube feeding. CONCLUSION: Post-extubation dysphagia is frequent and needs to be investigated.

Alteration of Swallowing and Ventilation Coordination in Respiratory Diseases in Small Mammals.

In human and animal, swallowing and ventilation are coordinated to avoid laryngeal penetration or tracheal aspiration, and respiration is interrupted during swallowing and resumes in the expiratory phase. Some respiratory diseases may alter this coordination due to impaired lung function. The aim of this study was to evaluate swallowing-ventilation coordination in unrestrained rats with pulmonary emphysema or with pulmonary fibrosis. Two protocols were performed in 38 male Sprague-Dawley rats (2-3 months, 250-300 g): pulmonary emphysema and pulmonary fibrosis. Ventilation during swallowing and swallowing-ventilation coordination were recorded using a whole-body plethysmography and video recordings. The rats were free to take water after 24 h without drinking. Compared to control groups, swallowing frequency was significantly higher in rats with pulmonary emphysema and there was a decrease of swallows during expiration in rats with pulmonary emphysema and in rats with pulmonary fibrosis. In this study, we show that respiratory diseases are associated with changes in swallowing-ventilation coordination and hypothesize that they increase the risk of aspiration.

Effect of liquid properties on swallowing and ventilation coordination in rats.

BACKGROUND: One aspect of rehabilitation in swallowing disorders is to change liquid properties. The objective of our study was to test how liquid properties could improve oropharyngeal dysphagia and swallowing and ventilation coordination in an animal model. METHODS: Forty-two healthy male rats were distributed in six groups, including a control group. Rats were deprived of water for 24 h and then each group was administered liquid with different properties: tap water, sugar water, sparkling water, salt water, cold water, and acidic water. Rats were studied without and with oropharyngeal dysphagia achieved by unilateral section of the hypoglossal nerve. Swallowing and ventilation were analyzed by barometric plethysmograph. KEY RESULTS: In healthy rats, swallowing occurred during expiratory time for all liquid properties. Most deglutitions were during expiratory time for all liquid properties (88±12%) and were not modified. There was an increase in VT/TI during swallowing with sparkling water and cold water (P<.05). In the operated groups, rats had significantly fewer swallows with tap water (P<.05) and significantly more swallows with sparkling water (P<.001), sugar water (P<.001) and cold water (P<.001) during expiratory time. The mean inspiratory volume (VT/TI) increased with sparkling water (P<.05). CONCLUSION AND INFERENCES: Sparkling water seemed to improve swallowing and ventilation coordination in an animal model, to be confirmed in a study including patients with oropharyngeal dysphagia.

Swallowing Disorders in Severe Brain Injury in the Arousal Phase.

The objective of this study was to determine the clinical characteristics of swallowing disorders in severe brain injury in the arousal phase after coma. Between December 1, 2013 and June 30, 2014, eleven patients with severe acquired brain injury who were admitted to rehabilitation center (Male 81.8 %; 40.7 ± 14.6 years) were included in the study. Evaluation of swallowing included a functional examination, clinical functional swallowing test, and naso-endoscopic swallowing test. All patients had swallowing disorders at admission. The first functional swallowing test showed oral (77.8 %) and pharyngeal (66.7 %) food bolus transport disorders; and alterations in airway protection mechanisms (80 %). Swallowing test under endoscopic control showed a disorder in swallowing coordination in 55.6 % of patients tested. Seven (63.6 %) patients resumed oral feeding within an average of 6 weeks after admission to rehabilitation center and 14 weeks after acquired brain injury. Six (85.7 %) of these seven patients continued to require modified solid and liquid textures. Swallowing disorders are a major concern in severe brain injury in the arousal phase. Early bedside assessment of swallowing is essential for detection of swallowing disorders to propose appropriate medical rehabilitation care to these patients in a state of altered consciousness.

Impact of deep brain stimulation on pharyngo-esophageal motility: a randomized cross-over study.

BACKGROUND: Bilateral subthalamic nucleus (STN) stimulation is used to alleviate Parkinson's disease (PD) motor symptoms. Recently, it has been shown that this therapeutic also increased gut cholinergic contractions. We therefore investigated the effect of STN stimulation on esophageal motility in an interventional randomized study. METHODS: Sixteen humans PD patients (4 women, 12 men; age: 62.4 ± 9.3-years old) who underwent STN stimulation for at least 6 months were randomly evaluated with either stimulator turned OFF then ON, or inversely. Esophageal high resolution manometry was performed at the end of each ON and OFF period, with a 5 min resting period followed by ten swallows of 5 mL. KEY RESULTS: During the ON, an increase in the distal contractility index was found (OFF: 1750 ± 629 vs ON: 2171 ± 755 mmHg/cm/s; p = 0.03), with no difference in the distal front velocity. A decrease in the integrative relaxation pressure of the lower esophageal sphincter (LES) was noted (OFF: 11.1 ± 1.8 mmHg vs ON: 7.2 ± 1.8 mmHg; p < 0.05) in ON. The LES resting pressure remained unchanged during the two periods. This resulted in a decrease in the intrabolus pressure (p = 0.03). No difference was observed for the upper esophageal sphincter, nor the pharyngeal contraction amplitude and velocity. CONCLUSIONS & INFERENCES: In conclusion, STN stimulation in PD patients increased esophageal body contractions and enhanced the LES opening. This suggests that the nigrostriatal-striatonigral loop is involved in the control of esophageal motility.

What are the perspectives for ventilated tetraplegics? A French retrospective study of 108 patients with cervical spinal cord injury.

OBJECTIVE: Tetraplegic patients are often difficult to manage in intensive care units (ICU). The aim of our study was to calculate the incidence of patients in ICU with cervical spinal cord injury with special focus on tetraplegic patients on ventilation support and their future perspectives. MATERIALS AND METHODS: This retrospective study included patients with cervical spinal cord injury in Upper Normandy, between 2002 and 2012. Data analyzed included age, sex, past medical history, date of onset of quadriplegia, level of neurological involvement, AIS grade, and ventilatory status. RESULTS: One hundred and eight patients were included (49.0 ± 21.1 years). The most common etiology was fall (50 patients [46.3%]). Incidence was calculated at 12.7 per one million inhabitants. Tracheotomy was performed in 40.7% of patients. Long-term mechanical ventilation was required for 6.5%. At the end of the study, 9 patients (9.6%) were permanently hospitalized, 61 patients (64.9%) had returned home but none of the four ventilated patients had been discharged. CONCLUSION: The conclusion of this work is that the future of highly tetraplegic patients is compromised, especially for those who remain reliant on mechanical ventilation.

Can multichannel intraluminal pH-impedance monitoring be limited to 3 hours? Comparison between ambulatory 24-hour and post-prandial 3-hour recording.

Esophageal multichannel intraluminal pH-impedance recording (MII) is now a valid technique for determining the acidic, liquid, gas or mixed nature of gastroesophageal reflux episodes. However, some recordings may stop prematurely due to technical reasons or poor patient tolerance of the probe. Therefore, we questioned whether analysis of post-prandial 3-hour recording could predict the results obtained in ambulatory 24-hour recording. Fifty patients with symptoms of gastroesophageal reflux disease were investigated. For each patient, post-prandial 3-hour MII was recorded after a test meal, then followed by ambulatory 21-hour MII. Correlation between the total number of liquid reflux events in the 3-hour and 24-hour recordings was elevated (R=0.71; P<0.001), with better correlation for acid (R=0.80; P<0.001) and weak acid reflux (R=0.56; P<0.001) than non-acid reflux (R=0.44; P<0.01). Sensitivity and specificity of 3-hour recording in detecting elevated liquid reflux over 24 hours (id>75reflux/24 h) were 49% and 100%, respectively, for 8 or less liquid/mixed reflux events per 3 hours, and 78% and 88%, respectively for 15 or more liquid/mixed reflux events per 3 hours. The sensitivity and specificity of symptom association probability (SAP) calculated over 3 hours were 56% and 91%, respectively. In conclusion, we identified relevant indicators on the 3-hour post-prandial recording likely to give accurate prediction of absence or presence of gastroesophageal reflux disease from 24-hour MII recording.

Effect of transcranial magnetic stimulation on rectal sensitivity in irritable bowel syndrome: a randomized, placebo-controlled pilot study.

AIM: Repetitive transcranial magnetic stimulation (rTMS) applied to the motor cortex can induce analgesic effects in patients with chronic pain syndromes through its effect on central pain-modulatory systems. Our aim was to evaluate the effect of rTMS on rectal sensitivity in irritable bowel syndrome (IBS) patients. METHOD: In this randomized, sham-controlled, proof-of concept trial, 21 IBS patients (11 women and 10 men; mean age 44.0 ± 12.6 years) were randomized, using a double-blind crossover protocol, to active or sham rTMS for 5 days of treatment. The primary outcome was the increase in the pressure pain threshold after rTMS. Secondary outcomes were the changes in maximum tolerated rectal volume, rectal compliance and average pain intensity between baseline and the end of the treatments. RESULTS: There were no statistically significant differences between active and sham rTMS in terms of an increase in the pressure pain threshold, maximum tolerated volume and rectal compliance at the end of the treatments compared with baseline. However, in the subgroup of patients with the most marked rectal hypersensitivity, the volume threshold was significantly improved by active, but not by sham, rTMS (P = 0.03). Patients experienced a significant improvement in pain regardless of the type of stimulation. CONCLUSION: This pilot study failed to demonstrate any benefit of rTMS on our primary end-point. However, the effect of rTMS on rectal tolerated volume in the most hypersensitive patients was encouraging enough to plan more powered studies.

Evoked pressure curves from the external anal sphincter following transcranial magnetic stimulation in healthy volunteers and patients with faecal incontinence.

AIM: The hypothesis was tested that evoked pressure curves (EPCs) after transcranial magnetic stimulation (TMS) would provide additional neuropathophysiological information on the descending pathways to the external anal sphincter (EAS) in patients with faecal incontinence (FI). METHOD: Twenty-five healthy subjects and 69 patients with FI were investigated. TMS was applied to the vertex, and EPCs were recorded with a probe placed through the EAS. TMS was performed with the EAS at rest and during contraction (facilitated responses). At least three responses were recorded for each modality. Clinical data and anorectal manometric, electrophysiological perineal and transanal ultrasound recordings were compared with respect to the EPC results. RESULTS: There was no statistically significant difference between the EPCs of healthy subjects and FI patients. Twenty-three per cent of the FI patients had abnormal EPC latencies, with significantly lower voluntary contraction amplitudes (P = 0.03) and significantly higher rectal sensation (P = 0.04) than the other group. We found no significant difference between FI patients with and without abnormal EPC latencies in terms of clinical characteristics and electrophysiological and endoanal ultrasound parameters. There was no difference in the identified causes of the FI between the two groups. CONCLUSION: As abnormal EPC latencies were found in 23% of FI patients with no known central neurological disease, abnormal EPC latencies might reveal undetected lesions of descending pathways in patients with FI.

Modification in swallowing and ventilation co-ordination during hypercapnia, hypoxia, and tachypnea in unrestrained animals.

BACKGROUND: It has been demonstrated that aspirations could occur during respiratory failure, explained by a lack of co-ordination between swallowing and ventilation. To test this hypothesis, we examined the co-ordination of ventilation and swallowing in a completely unrestrained rat model during different level of hypercapnia, during hypoxia, and during tachypnea. METHODS: A total of 50 male Wistar rats (250-350 g) were studied in a barometric plethysmograph to analyze swallowing and ventilation during swallowing, at different gas concentration [room air (G1), 10% of O2 and 0% of CO2 (G2), 21% of O2 and 5% of CO2 (G3), 21% of O2 and 10% of CO2 (G4), tachypnea (G5)]. KEY RESULTS: During hypoxia, there was no difference between G2 and G1 regarding the swallowing parameters and ventilatory parameters. During hypercapnia, there was an increase in swallowing during inspiration in G4 (16 ± 20%P < 0.01) compared with G1. The analysis of ventilatory parameters during swallowing showed an increase in tidal volume (VT) and mean inspiratory time (VT/TI) (P < 0.001) with no change in respiratory cycle duration (TTOT), inspiratory time (TI), and expiratory time (TE) when compared with G1. During tachypnea (G5), the VT decreased (P < 0.05) without any change in VT/TI. CONCLUSIONS & INFERENCES: Our results on animal demonstrated that hypercapnia increased swallowing during inspiration, which was not the case for tachypnea or hypoxia, and could explain some aspirations during respiratory failure.

Oropharyngeal dysphagia in amyotrophic lateral sclerosis alters quality of life.

Dysphagia is one of the most important complications encountered in amyotrophic lateral sclerosis (ALS). Our aim was to determine whether oropharyngeal dysphagia impacted the quality of life (QoL) of patients with ALS. Thirty consecutive patients were recruited (31-82 years, 18 men). Swallowing function was evaluated using a standardised videofluoroscopic barium swallow. All the patients completed a specific questionnaire on quality of life in dysphagia (SWAL-QoL) immediately after the videofluoroscopy. The results of dysphagia outcome severity scale separated 14 patients with oropharyngeal dysphagia and 16 with normal swallowing function. There was no difference in the average age, weight and body mass index of the two groups (dysphagic patients: 68 ± 11 kg versus non-dysphagic patients: 69 ± 14 kg). Most of the dysphagic patients had a bulbar affection based on their Norris scores which determine the importance of cranial nerves illness (20 ± 8), significantly lower than those of the non-dysphagic patients (35 ± 5) (P < 0·0001). There was no difference in the neurological peripheral symptoms evaluated by Amyotrophic Lateral Sclerosis Functional Rating Scale scores (dysphagic patients: 26 ± 7 versus non-dysphagic patients: 27 ± 8) (ns). The swallowing quality of life questionnaire revealed that the dysphagic patients had significant burden (P < 0·001). They were affected by the necessity to applied a food selection (P < 0·01), by the increase in eating duration (P < 0·05) and described a decrease in eating desire (P < 0·05). They complained of fear regarding the risk of dysphagia (P < 0·05). They also described difficulties with oral communication (P < 0·001). All of those complained about dysphagia which impacted directly mental health (P < 0·05) and social life (P < 0·05). In conclusion, oropharyngeal dysphagia is a common symptom accompanying ALS, which alters the patient's QoL, especially social health.

Clinical screening of oropharyngeal dysphagia in patients with ALS.

OBJECTIVE: It is a major issue to diagnose and detect oropharyngeal dysphagia in the early stage of ALS in order to avoid pulmonary and nutritional complications. The aim of this study was to validate a simple clinical test, the Volume-Viscosity Swallow Test (V-VST), to detect oropharyngeal dysphagia in this population. PATIENTS AND METHODS: Twenty patients were included in this study (mean age: 66.1 ± 8.13, six women). All patients had their swallowing function assessed by videofluoroscopy and V-VST. RESULTS: Among these 20 patients, 15 presented oropharyngeal dysphagia, diagnosed by videofluoroscopy, and five had normal swallowing. Norris score was lower in patients with oropharyngeal dysphagia compared to the patients with normal swallowing (27 ± 6 versus 36 ± 2; P=0.003). Among the 15 patients with oropharyngeal dysphagia, 14 had abnormal V-VST, and only one had normal V-VST. The sensibility of V-VST to detect oropharyngeal dysphagia in these patients with ALS was of 93%, and the specificity was of 80% (P=0.007). There was no significant difference between the two populations for ALSFRS score (22 ± 6 versus 20 ± 6) and body mass index (BMI) (26 ± 6 versus 26 ± 6 kg/m(2)). CONCLUSION: The V-VST presented good sensibility and specificity. It may be interesting to use it systematically for the detection of oropharyngeal dysphagia in ALS, after confirming these results on a wider patient sample.

Effect of lingual paralysis on swallowing and breathing coordination in rats.

BACKGROUND: The tongue plays an important role in both swallowing and breathing. Lingual motor deficits with consequences for swallowing are often observed in many neurological disorders. However, the impact of such deficits on swallowing and breathing coordination is unknown. OBJECTIVE: Our objective was to study the swallowing and ventilatory patterns in rats with unilateral lingual paralysis. METHODS: Our study was carried out on 10 Wistar rats. Respiratory variables in unrestrained and healthy animals were measured at rest and during water swallowing using whole-body plethysmography and a video camera. The procedure was repeated after unilateral sectioning of the hypoglossal nerve (XII). Swallowing frequency and occurrence during inspiration and expiration, tidal volume, total time of the ventilatory cycle and respiratory drive were assessed. RESULTS: Unilateral sectioning of the hypoglossal nerve led to a swallowing deficit and drooling. Respiratory rhythm and ventilatory drive (16.39±2.13 ml/s vs. 13.67±1.28 ml/s) during swallowing decreased after hypoglossal nerve sectioning but were unaffected during rest without swallowing, while swallowing rate (17±5/15s) and occurrence during respiratory cycle phases did not change. CONCLUSIONS: A swallowing deficit induced by lingual paralysis decreased the ventilatory drive during swallowing. This may be a mechanism to reduce or prevent pulmonary aspiration.

Submental sensitive transcutaneous electrical stimulation (SSTES) at home in neurogenic oropharyngeal dysphagia: a pilot study.

OBJECTIVE: Oropharyngeal dysphagia is frequent in chronic neurological disorders and increases mortality, mainly due to pulmonary complications. Our aim was to show that submental sensitive transcutaneous electrical stimulation (SSTES) applied during swallowing at home can improve swallowing function in patients with chronic neurological disorders. METHODS: Thirteen patients were recruited for the study (4 f, 68 ± 12 years). They all suffered from neurogenic oropharyngeal dysphagia. We first compared the swallowing of paste and liquid with and without SSTES. Thereafter, the patients were asked to perform SSTES at home with each meal. Swallowing was evaluated before and after six weeks of SSTES using the SWAL-QoL questionnaire. RESULTS: With the stimulator switch turned on, swallowing coordination improved, with a decrease in swallow reaction time for the liquid (P<0.05) and paste boluses (P<0.01). Aspiration scores also decreased significantly with the electrical stimulations (P<0.05), with no change in stasis. At-home compliance was excellent and most patients tolerated the electrical stimulations with no discomfort. A comparison of the SWAL-QoL questionnaires after 6 weeks revealed an improvement in the burden (P=0.001), fatigue (P<0.05), and pharyngeal symptom (P<0.001) scales. CONCLUSION: The present study demonstrated that SSTES is easy to use at home and improves oropharyngeal dysphagia quality of life.

Involvement of the aero-digestive tract in swallowing-ventilation coordination: an animal study.

BACKGROUND: The precise coordination of swallowing and ventilation is considered an important mechanism for minimizing the risk of pulmonary aspiration. The aim of this study was to test the hypothesis that the aero-digestive tract is involved in swallowing-ventilation coordination in rats. METHODS: The goal of the first part of the study was to characterize swallowing events associated with ventilation signals obtained using a barometric plethysmograph. This was done in seven rats with the help of esophageal electromyograms. Thereafter, swallowing-ventilation coordination was assessed in 15 rats with right unilateral vocal cord paralysis and 10 rats following oropharyngeal anesthesia. KEY RESULTS: In healthy animals, 92 ± 11% of swallows occurred during expiration and 8 ± 11% during inspiration. Swallow frequency and swallowing characteristics based on ventilation did not change following unilateral laryngeal paralysis. Swallows during expiration decreased (71 ± 9%, P < 0.01) while swallows during inspiration increased (29 ± 11%, P < 0.01) following oropharyngeal anesthesia with lidocaine. CONCLUSIONS & INFERENCES: Our findings using a rat model need to be confirmed, however, they indicated that a rat model can be used to study oropharyngeal dysphagia and that laryngo-pharyngeal anesthesia alters swallowing-ventilation coordination.

Impact of swallowing and ventilation on oropharyngeal cortical representation.

Our aim was to determine whether ventilation and swallowing tasks can modify oropharyngeal cortical motor organisation. Mylohyoid motor-evoked potentials (MEP) induced by non-focal (NF) and focal (F) magnetic stimulations were recorded in nine healthy volunteers four times, with 1 week between each recording. Baseline values were evaluated and their reproducibility was assessed 1 week later. Thereafter, the subjects were asked to perform swallowing and ventilation tasks in random order 15 min per day for 1 week. The NF MEP amplitudes after the swallowing and ventilation tasks increased after effortful swallows (p<0.001) and ventilation efforts (p<0.001). The F MEP amplitudes obtained after focal cortical stimulations increased after effortful swallows (p<0.01) and ventilation efforts (p<0.05). The cortical magnitude of the oropharyngeal muscle representation increased after swallowing practice (p<0.01). In conclusion, swallowing and ventilation tasks modified the motor cortex of oropharyngeal muscles and should be evaluated for use in rehabilitation strategies.

Validation in French of the SWAL-QOL scale in patients with oropharyngeal dysphagia.

A quality-of-life (QOL) questionnaire specifically designed for patients with oropharyngeal dysphagia (SWAL-QOL) has been elaborated and validated by Colleen McHorney. The aim of the present study was to validate the French translation of the SWAL-QOL in 73 patients with either post-stroke or post-surgical oropharyngeal dysphagia. The French version was considered understandable and acceptable by the study patients, who completed the questionnaire in approximately 20 minutes. However, 32 patients needed help in filling out the questionnaire-mostly in reading the questions and writing the answers. Completion was excellent, although seven patients missed one item. Analysis of convergent validity of the French version showed good correlation between items and the corresponding scale. Validity convergence was excellent for all the different items, with a correlation between each item and its own scale that was always greater than 0.40. Internal coherence was also excellent, with Cronbach's alpha coefficient greater than 0.7. Patients with oropharyngeal dysphagia have a poor QOL, as reflected by their very low scores. The lowest scores were related to the impact of swallowing disorders on the QOL (47+/-30) and on mental health (51+/-31). This study also demonstrated the linguistic and psychometric validity of the French version of the SWAL-QOL questionnaire.

Poststroke dysphagia rehabilitation by repetitive transcranial magnetic stimulation: a noncontrolled pilot study.

Poststroke dysphagia is frequent and significantly increases patient mortality. In two thirds of cases there is a spontaneous improvement in a few weeks, but in the other third, oropharyngeal dysphagia persists. Repetitive transcranial magnetic stimulation (rTMS) is known to excite or inhibit cortical neurons, depending on stimulation frequency. The aim of this noncontrolled pilot study was to assess the feasibility and the effects of 1-Hz rTMS, known to have an inhibitory effect, on poststroke dysphagia. Seven patients (3 females, age = 65 +/- 10 years), with poststroke dysphagia due to hemispheric or subhemispheric stroke more than 6 months earlier (56 +/- 50 months) diagnosed by videofluoroscopy, participated in the study. rTMS at 1 Hz was applied for 20 min per day every day for 5 days to the healthy hemisphere to decrease transcallosal inhibition. The evaluation was performed using the dysphagia handicap index and videofluoroscopy. The dysphagia handicap index demonstrated that the patients had mild oropharyngeal dysphagia. Initially, the score was 43 +/- 9 of a possible 120 which decreased to 30 +/- 7 (p < 0.05) after rTMS. After rTMS, there was an improvement of swallowing coordination, with a decrease in swallow reaction time for liquids (p = 0.0506) and paste (p < 0.01), although oral transit time, pharyngeal transit time, and laryngeal closure duration were not modified. Aspiration score significantly decreased for liquids (p < 0.05) and residue score decreased for paste (p < 0.05). This pilot study demonstrated that rTMS is feasible in poststroke dysphagia and improves swallowing coordination. Our results now need to be confirmed by a randomized controlled study with a larger patient population.