Movement-Related Cortical Potentials Associated with Saliva and Water Bolus Swallowing

The purpose of this study was to document the movement-related cortical potentials associated with saliva and water bolus swallowing in seven right-handed healthy humans. As the subjects performed a saliva or water bolus swallowing task, electroencephalograms with electrodes at C3, Cz, and C4 and an electromyogram of the mylohyoid muscle complex were recorded. The early slope, referred to as the Bereitschafts potential, before saliva swallowing was significantly steeper than that before water bolus swallowing. Positive potential amplitude during water bolus swallowing was significantly larger than that during saliva swallowing. Negative slope and motor potential were not clearly present during performance of either swallowing task. Those findings imply that the features of movement-related cortical potential associated with pharyngeal swallowing are different from those associated with limb movement, and that both the cortical process associated with sensory information of pharyngeal swallowing and the cortical preparatory process of pharyngeal swallowing depend on the type of swallowing task.     

Acoustic Study of Pharyngeal Swallowing as a Function of the Volume and Consistency of the Bolus

Cervical auscultation is a noninvasive technique for the exploration of swallowing and has been used since the 1960s. The aim of our study was to describe how the volume and consistency of the bolus affect swallowing acoustic sound characteristics in healthy subjects. Twenty-three subjects aged from 20 to 59 years were included (13 women and 10 men). A microphone mounted on a stethoscope chest piece, positioned on the skin on the right side in front of the posteroinferior border of the cricoid cartilage, was used; it was connected to a computer for acoustic recordings. Each subject swallowed 2-, 5-, and 10-ml aliquots of water, yogurt, and mashed potato. Each bolus was administered once, with a period of at least 30 s between each swallow. For each recorded sound, the total duration of the sound and the duration of each sound component (SC) (SC1, SC2, and SC3) and interval (IT1 and IT2) between the SCs were measured. For all records, the average duration of acoustic measures was calculated. Differences according to the volume and the consistency of the swallowed bolus were assessed using Student’s t test for paired data. We calculated the percentage of recordings that included each SC. We also compared results between men and women using Student’s t test. We successfully interpreted 540 of the 621 (87 %) records. The results indicated that the average total duration of the sound, and especially the average duration of SC2, increased with increasing volume and was greater for mashed potato than for the boluses of other consistencies. SC2 was present in all of the records.     

Bolus Consistency and Swallowing in Children and Adults

Research has shown that swallowing in adults is affected by bolus consistency. Little is known, however, regarding the effect of bolus consistency on swallowing in children. Electromyographic (EMG) data from typically developing five- and eight-year-old-children and adults were obtained from the following muscles as they swallowed boluses of different consistencies: (1) right upper lip, (2) right lower lip, (3) submental, and (4) laryngeal strap. Signal analyses included calculating EMG onset and offset and average EMG amplitude of muscle activity during swallowing. Findings revealed that by five years of age, children employ adultlike control strategies during swallowing: significant differences in duration and magnitude of muscle activity resulted as a function of bolus consistency. General observations revealed, however, that swallowing in children is characterized by muscle activity that is shorter in duration. Similarities and differences in the biomechanics of swallowing between children and adults are important to consider during clinical evaluations and treatment of children with dysphagia.     

Normal Swallowing Acoustics Across Age, Gender, Bolus Viscosity, and Bolus Volume

Cervical auscultation has been proposed as an augmentative procedure for the subjective clinical swallowing examination due to the tangible differences between normal and dysphagic swallowing sounds. However, the research is incomplete regarding cervical auscultation and swallowing acoustics in that the differences between the sounds of normal versus dysphagic swallowing have yet to be fully understood or quantified. The swallows of 96 reportedly healthy adults, balanced for gender and divided into younger, middle, and older age groups, were audio-recorded while ingesting several boluses of varying viscosity and volume. The audio signals were then analyzed to determine their temporal and acoustic characteristics. Results indicated increasing pharyngeal swallowing duration with increasing age, bolus viscosity, and bolus volume. In addition, an increased duration to peak intensity with increasing age was found in one of our two analyses, as well as with some of the more viscous versus less viscous boluses. Men and older persons produced higher peak intensities and peak frequencies than women and younger persons. Thin liquids were produced with more intensity than honey or more viscous boluses, and with greater frequency than mechanical soft solids. Larger volumes resulted in greater peak frequency values. Some of the acoustic measurements appear to be more useful than others, including the duration of the acoustic swallowing signal and the within-subjects peak intensity variable. We noted that differences in swallowing acoustics were more related to changes in viscosity rather than volume. Finally, within-participant observations were more useful than between-participant observations.     

Effect of Age and Bolus Variables on the Coordination of the Glottis and Upper Esophageal Sphincter during Swallowing

We studied 1) the effect of age and bolus variables on a) the coordination of deglutitive vocal cord adduction and upper esophageal sphincter (UES) relaxation and b) the duration of deglutitive vocal cord adduction; 2) the effect of the presence of a manometric catheter across the UES on the deglutitive glottal function; and 3) the temporal relationship between deglutitive vocal cord closure and swallow-induced apnea. We studied 10 young (23 ± 2 yr) and 10 healthy elderly (73 ± 2 yr) volunteers by concurrent videoendoscopy, UES manometry, respirography, and submental surface electromyography. In both groups the onset of vocal cord adduction preceded the onset of UES relaxation, deglutitive apnea, and submental electromyogram swallowing signal. In both groups, bolus volume and temperature did not have any significant effect on the duration of deglutitive vocal cord adduction. In both young and elderly volunteers, water swallows, compared with dry swallows, significantly shortened the interval between the onset of deglutitive vocal cord adduction and the onset of UES relaxation.
In conclusion, coordination between deglutitive glottal and UES function, as well as the duration of deglutitive vocal cord adduction, is preserved in the elderly. Bolus volume and temperature do not have a modulatory effect on the duration of vocal cord closure, but water swallow shortens the interval between the onset of glottal closure and UES relaxation. This shortened interval may contribute to the safety of the airway during swallowing of liquid volumes.     

Effects of Age, Gender, Bolus Volume, and Trial on Swallowing Apnea Duration and Swallow/Respiratory Phase Relationships of Normal Adults

The effects of age, gender, bolus volume, and trial on swallowing apnea duration (SAD) and swallow/respiratory phase relationships were examined. Sixty adults, composed of ten males and ten females in each of three age groups (i.e., 20–39, 40–59, and 60–83 years), participated. SAD was assessed via nasal airflow during saliva swallows and 10-, 15-, 20-, 25-mL bolus volumes across three trials. Results revealed SAD is consistent across trial (p>0.05). Significant main effects of age, gender, and bolus volume were found (p<0.05), i.e., elderly adults had longer SAD than young and middle-aged adults; women had longer SAD than men; and SAD increased as bolus volume increased. With respect to saliva swallows, a significant interaction of age by gender was found (p<0.05), i.e., males exhibited a decrease in SAD with increasing age while females exhibited an increase in SAD with increasing age. Concerning swallow/respiratory phase relationships, the pattern of exhale–swallow–exhale was evident during 62% of participants' swallows. Furthermore, age, gender, or bolus volume did not predict the pattern of exhale–swallow–exhale (p>0.05). Submitted February 23, 2000; accepted October 2, 2000     

炎症信号与心房颤动

心房颤动是病理生理学机制复杂的一种心律失常。大量的实验和临床资料表明,心房重构的病理生理学与炎症密切相关。心房重构和炎症之间的联系机制复杂,而不同的潜在疾病和条件均可能影响这些通路。炎症标志物与心房颤动的发生和发展以及射频导管消融术后复发有关。但最常用的抗炎药,如糖皮质激素,增加了感染、出血和高血糖的风险。另外抑制的治疗方法,如细胞因子,又严重干扰正常的心肌功能,在这种情况下,开发特定的抗炎干预措施似乎更具有挑战性和复杂性。这篇综述简要概述了心房颤动与C反应蛋白、肿瘤坏死因子-α、转化生长因子、白介素-6、白介素-10和白介素-37之间的相关性,以及探讨可能用于通过减轻炎症反应预防或治疗心房颤动的药物、减少心房颤动的危险因素和改变生活方式等方法作为上游治疗思路。     

Effects of Age and Stimulus on Submental Mechanomyography Signals During Swallowing

Mechanomyography (MMG) is the measurement of the vibrations associated with muscle contraction. As an indicator of muscle activity in swallowing, MMG has several potential advantages over conventional electromyography (EMG), including robustness to variations in sensor placement, perspiration, and food spillage. The objective of this study was to investigate the effects of participant age and stimulus on submental muscle activity as measured by MMG. Nasal airflow was utilized as a reference signal. Four liquid stimuli were investigated: water, nectar-thick and honey-thick apple juices, and a thin-liquid barium suspension. Each of 15 healthy adults completed nine swallowing sequences, each consisting of four discrete swallows via a self-administered cup-drinking task, with an MMG sensor at a midline submental location and a nasal cannula at the nares. Muscle activity and swallowing apneas in the signals were identified with pseudo-automatic segmentation algorithms. Various timing and amplitude features were extracted from each segmented swallow. Muscle activity onset preceded the onset of swallow apnea. Significant main effects of stimulus were found for the duration of muscle activity and for the time difference between the offsets of muscle activity and swallow apnea. No other main or interaction effects were significant. In general, the timing and amplitude variations of submental muscle activity revealed by MMG seem to agree with previously reported findings using EMG. The minor discrepancies between the results of this study and those of previous EMG studies are likely due to differences in experimental tasks. MMG may serve as an alternative measure of muscle activity during swallowing and further investigation is warranted.

Swallowing Kinematics and Factors Associated with Laryngeal Penetration and Aspiration in Stroke Survivors with Dysphagia

The purpose of this study was to investigate swallowing kinematics and explore kinematic factors related with penetration-aspiration in patients with post-stroke dysphagia. Videofluoroscopic images of 68 patients with post-stroke dysphagia and 34 sex- and age-matched healthy controls swallowing a thin liquid were quantitatively analyzed using two-dimensional motion digitization. The measurements included the movement distances and velocities of the hyoid and larynx, and the maximal tilt angles and angular velocities of the epiglottis. All velocity variables were significantly decreased in the stroke patients compared to the controls. There was a significant difference in the maximal horizontal displacement of the larynx, but there were no significant differences in other displacements of the larynx, the maximal displacements of the hyoid bone, and the maximum tilt angle of the epiglottis between the two groups. The maximal tilt angle of the epiglottis was lower in the aspiration subgroup than in the no penetration/aspiration and penetration subgroups as well as the controls. The maximal tilt angle from the y axis showed a dichotomous pattern at 90° of the angle, and all 11 patients with an angle <90° showed either penetration or aspiration. In the ROC curve of the angle for prediction of aspiration, the area under the curve was 0.725 (95 % CI 0.557–0.892, P = 0.008). This study suggested that sluggish rather than decreased hyolaryngeal movements during swallowing are a remarkable feature of post-stroke dysphagia. The association of reduced epiglottic movement with the risk of aspiration in patients with post-stroke dysphagia was supported by the quantitative analysis.     

Meat Bolus Impaction of the Lower Esophagus Associated with a Paraesophageal Hernia

Ferrucci and Long recently reported the relief of esophageal food impaction with the use of intravenous glucagon in three patients. Our first experience in using this new procedure was very successful and gratifying. The essence and purpose of this brief communication is to record and further substantiate the efficacy of a new treatment modality.     

Incidence of Pneumonia After Videofluoroscopic Swallowing Study and Associated Factors

Pneumonia after videofluoroscopic swallow study (VFSS) is sometimes considered to be caused by aspiration during VFSS; however, to our knowledge, a relationship between these events has not been clearly investigated. The aim of this study was to assess the incidence of VFSS-related pneumonia and related factors. Overall, 696 VFSS cases were retrospectively reviewed. Cases in which blood culture was performed within 3 days after VFSS due to newly developed infectious signs were considered as post-VFSS infection cases. Pneumonia was suspected when there was some evidence of respiratory infectious signs in clinical, radiological, and laboratory findings. The underlying disease, clinical signs, and VFSS findings of the pneumonia group were assessed. Among 696 cases, pneumonia was diagnosed in 15 patients. The patients in the pneumonia group tended to be older and had higher aspiration rate on VFSS than those in the non-pneumonia group. In the pneumonia group, 2 patients showed no aspiration during VFSS. In 6 patients, pneumonia developed after massive aspiration of gastric content in 5 patients and inappropriate oral feeding with risk of aspiration before VFSS in 1 patient. Only 7 patients (1.0 %) were finally determined as having VFSS-related pneumonia. In conclusion, the 72-h incidence of VFSS-related pneumonia was 1.0 %. Old age and severity of swallowing difficulty are associated with occurrence of pneumonia.     

Inflammatory Myopathy Associated with Anti-mitochondrial Antibody Presenting Only with Respiratory Failure

A 56-year-old woman presenting with type II respiratory failure was transferred to our hospital. She did not exhibit muscle weakness or elevated serum myogenic enzymes, but needle electromyography revealed myogenic changes in the limb muscles, and her blood tests were positive for anti-mitochondrial antibodies (AMA). Muscle histopathological findings included immune-mediated necrotizing myopathy, so she was diagnosed with inflammatory myopathy associated with AMA. After treatment with corticosteroids and noninvasive positive pressure ventilation, her symptoms improved. If a diagnosis of type II respiratory failure is difficult, inflammatory myopathy associated with AMA should be considered as a differential diagnosis.     

Preliminary Investigation of Swallowing Apnea Duration and Swallow/Respiratory Phase Relationships in Individuals with Cerebral Vascular Accident

Swallowing apnea duration (SAD) and swallow-respiratory phase relationships were examined in individuals with cerebral vascular accident (CVA) and dysphagia who aspirated (n = 11) and did not aspirate (n = 15). Simultaneous videofluoroscopic and respiratory measures were recorded across 5-, 10-, 15-, and 20-ml thin and thick liquid bolus trials. These data were also compared with that previously acquired with healthy older adults (n = 20). A moderate amount of systematic missing data was evidenced in the individuals who were dysphagic and especially those who aspirated subsequently limiting inferential analyses. Only 1 of the 11 participants who aspirated and 7 of the 15 who did not aspirate completed all 16 conditions. Six of the remaining ten who aspirated had missing data subsequent to termination of trials due to aspiration risk. The remaining four and seven of the eight who did not aspirate had missing data due to poor respiratory waveforms. From the remaining data, it was found that SAD and respiratory phase relationships differed among individuals with dysphagia and CVA (i.e., those who aspirate vs. those who do not aspirate) and healthy older adults. SAD was found to be longer for those who aspirated versus those who did not for all bolus viscosities and volumes with the exception of thick-liquid 10-ml boluses. In addition, SAD from those that aspirated was twice as long as that found in healthy older adults for all conditions. Regarding respiratory phase relationships, there was a difference between the proportions of respiratory patterns in those who aspirated versus those who did not. Those who aspirated demonstrated a markedly greater percentage of swallows that interrupted inhalation. In addition, the inhale-swallow-inhale pattern occurred with a greater frequency as swallowing severity increased. Healthy older adults, those who did not aspirate, and those who aspirated used the inhale-swallow-inhale pattern 0.1%, 3.0%, and 9.0%, respectively.