Effects of Bolus Volume on Pharyngeal Contact Pressure During Normal Swallowing

This cross-sectional study investigated the effect of bolus volume on contact pressure within the pharynx and upper esophageal sphincter (UES). Three solid-state manometric pressure sensors were placed transnasally into the pharynx and the proximal esophagus of 40 participants (gender equally represented and between the ages of 20 and 45 years). Participants completed five repetitions each of three swallowing conditions: 5-, 10-, and 20-ml water bolus swallows. Repeated-measures ANOVA revealed no significant differences in the amplitude of pharyngeal contact pressure between the three swallowing conditions (sensor 1: p = 0.627, sensor 2: p = 0.764). Similarly, for durational measures nonsignificant main effects were found at both sensor 1 (p = 0.436) and sensor 2 (p = 0.350). Significant differences were found in UES pressure between the three conditions of bolus swallows (p = 0.000), with negative pressure in the UES inversely proportionate to bolus volume. However, durational measures of UES relaxation pressure were not significantly different between all conditions (p = 0.473). This study demonstrates no significant pressure differences of amplitude and duration between swallowing conditions in the pharynx. At the level of the UES, smaller boluses generated greater negative pressure.     

Temporal Measurements of Pharyngeal Swallowing in Normal Populations

The purpose of this investigation was to examine the temporal differences among three measures of pharyngeal stage transition in 40 normal subjects. The measures were (1) Pharyngeal Delay Time (PDT), (2) Stage Transition Duration (STD), and (3) Delayed Pharyngeal Swallow (DPS). Results showed a significant difference between younger and older subjects for PDT and STD but not for DPS. No gender differences were observed. These data on normal subjects will be used for comparisons with stroke patients in future research. This work was performed at the University of Tennessee, Knoxville, Tennessee.     

Temporal and Durational Patterns Associating Respiration and Swallowing

This study obtained initial normative data on the temporal coordination of respiration and swallowing events in 12 young adults using a first-generation Respirodeglutometer. In addition, direction of airflow before and after deglutive apnea was obtained. Three swallows of two viscosities of bolus material were performed by each subject, yielding a total of 72 swallows. Qualitative and quanitative analyses were performed. Time of onset of submental surface electromyography and time of laryngeal movement were found to differ between males and females. Males began submental muscle contraction before females and laryngeal movement after females. Duration of deglutition apnea for all swallows was 0.75 ± 0.14 sec. Expiration occurred before the deglutition apnea 93% of the time and after the deglutition apnea 100% of the time. A modal pattern of events obtained with the Respirodeglutometer was present in 42% of the swallows, and an additional 47% had only one event differ from that order.     

Effects of Carbonated Liquids on Oropharyngeal Swallowing Measures in People with Neurogenic Dysphagia

Aspiration is common in adults with neurogenic dysphagia and pharyngeal delay. This can lead to dehydration, malnutrition, and aspiration pneumonia. Diet modifications aimed at reducing thin liquid aspiration are partially successful or unpalatable or both. Carbonated liquids show some potential in influencing swallowing behavior. However, there is a paucity of evidence to support this intervention. This study compares the effects of carbonated thin liquids (CTL) with that of noncarbonated thin liquids (NCTL) on oropharyngeal swallowing in adults with neurogenic dysphagia and examines the palatability of the CTL stimulus. Seventeen people with pharyngeal delay attended for videofluoroscopy (VFSS). Outcome measures were oral transit time (OTT), pharyngeal transit time (PTT), stage transition duration (STD), initiation of the pharyngeal swallow (IPS), penetration-aspiration scale (PENASP), and pharyngeal retention (PR). A modification of Quartermaster Hedonic Scale (AQHS) was employed to assess palatability of the CTL. CTL vs. NCTL significantly decreased penetration and aspiration on 5-ml (P?=?0.028) and 10-ml (P?=?0.037) swallows. CTL had no significant effect on OTT, PTT, IPS, and PR for any volume of bolus. Only one participant disliked the CTL stimulus. These findings support the hypothesis that oropharyngeal swallowing can be modulated in response to sensory stimuli. Implications for research and clinical practice are discussed.     

Sex Differences in the Effects of Obesity on Lung Volume

Background

Obesity is linked to variation of lung volume; however, it is still unclear whether a sex difference exists. The study aimed to find out the effect of obesity on lung volume and sex difference among the Chinese population.

Intra- and Interrater Variation in the Evaluation of Videofluorographic Swallowing Studies

The objective of this study was to determine the inter- and intrarater reliability in evaluating videofluoroscopic swallowing studies (VFSS). Participants included 4 physicians (3 physiatrists and 1 internist) and 5 speech-language pathologists with at least 5 years experience in evaluating VFSS. The main outcomes of the study were reliability ratios of positive and negative tests in inter- and intrarater evaluations. Raters independently rated each of 20 VFSS on two separate occasions. Traits evaluated included oral stage impairment, aspiration, pharyngeal retention, and several functional components: timing of swallow onset, adequacy of velopharyngeal apposition, laryngeal elevation, epiglottic tilt, pharyngeal contraction, and pharyngoesophageal (PE) segment opening. Reliability varied widely depending on food type and the trait under evaluation. Inter- and intrarater reliability ratios did not differ widely. Reliability ratios values typically were highest (greater than 90%) for aspiration, especially with solid food, and lowest for the functional components. It was concluded that inter- and intrarater reliability in VFSS are adequate for evaluating oral stage, laryngeal penetration, and aspiration and pharyngeal retention, but questionable for functional components.     

Use of Reaction Time in the Temporal Analysis of Normal Swallowing

This study was performed to establish the swallowing trigger by using the reaction time from an auditory stimulus. With this stable temporal starting point, we described the chronology of the different acoustic, electrophysiologic, and respiratory events that occurred during swallowing in a population of normal adults. We studied the swallowing reaction time (SRT) in 18 subjects aged 23 to 73 years by using acoustic, electroglottographic (EGG), and aerodynamic recordings. The chronology (the beginning of EGG activity, apnea, and respiratory sound and release) was identified in 91% of the recordings. The average SRT was 264 ms and the average swallowing duration was 977 ms, without any significant difference with respect to gender. The swallowing sound produced during apnea was composed of either two or three components. The reaction time procedure also demonstrated that the first sound component was unstable. By using this procedure for studying swallowing, we were able to stabilize the chronology of the different events, improve the subjects' attention, and establish a fixed benchmark for performing temporal measurements.     

Inter- and Intrajudge Reliability for Videofluoroscopic Swallowing Evaluation Measures

Interjudge reliability for videofluoroscopic (VFS) swallowing evaluations has been investigated, and results have, for the most part, indicated that reliability is poor. While previous studies are well-designed investigations of interjudge reliability, few reports of intrajudge reliability are available for VFS measures derived from frame-by-frame analysis that clinicians typically employ. The purpose of this study was to examine the inter- and intrajudge reliability of VFS examination measures commonly used to assess swallowing functions. No training to criteria occurred. VFS examinations were conducted on 20 patients who had suffered a stroke within six weeks and had no structural abnormalities or tracheostomies. Three clinical judges served as subjects and rated the VFS examinations from videotape using frame-by-frame analysis. A clinician's repeated review of measures employed in the 20 examinations indicated high intrajudge reliability for a number of measures, suggesting that an experienced clinician may employ consistent standards for rating certain VFS measures across patients and time. These standards appear to vary among clinicians and yield unacceptable interjudge reliability. The need to train clinicians to criteria to improve interjudge reliability is discussed.     

Preliminary Temporal Measurement Analysis of Normal Oropharyngeal Swallowing in Infants and Young Children

Temporal measures of normal pediatric oropharyngeal deglutition have not been studied. Knowledge of range and variation of normative temporal measures could define abnormal deglutition and assist in design of appropriate compensatory and rehabilitative treatment techniques. The purpose of this retrospective study was to determine temporal measurements for oral filling, oral transit, onset of laryngeal closure, time of bolus arrival at the valleculae, pharyngeal delay, pharyngeal transit, and UES opening. Videofluoroscopic swallow studies of 15 normally swallowing pediatric subjects were divided into three age groups and method of liquid delivery. Mean, standard deviation, percentages, and extension of the median were utilized to determine relationships of temporal measures. Mean temporal duration increased with age for oral filling, oral transit time, time of laryngeal closure, UES opening, and pharyngeal delay time. However, no significant differences were found between age groups indicating a deglutitive biomechanical adaptation to growth of the oral and pharyngeal cavity. Feeding method for bottle versus cup mean duration increased for oral transit time, laryngeal closure time, UES opening, and pharyngeal delay time. Bolus head location relative to onset of laryngeal vestibule closure changed with increased age and method of feeding. Temporal measures were not significantly different for age groups or feeding methods. Bolus location was at or fully contained in the valleculae at the onset of laryngeal closure and appeared to be a normal finding in functional pediatric swallows and is not indicative of a delay or disorder.     

Swallowing Lateralization: The Effects of Modified Dual-Task Interference

A modified dual-task paradigm was designed to learn whether swallowing functions are selectively mediated by the left or right hemisphere. Healthy right-handed men (N = 38) were studied using videofluoroscopy to examine continuous straw drinking at baseline and with three interference conditions (silent word repetition, line orientation, finger tapping). Results indicate that activation of both right and left hemispheres can interfere with some swallowing behaviors. Findings suggest possibly different roles of the two hemispheres in the mediation of swallowing and support the notion that specific components of swallowing may be preferentially mediated by the left versus the right hemisphere.     

Prescription Drugs and Their Effects on Swallowing

The impact of medications on the physiology of swallowing has received much attention in dysphagia literature. This article reviews the potential effects of medications commonly prescribed in an adult continuing care and rehabilitation facility on swallowing. An audit of medications prescribed to 153 adults accessing age-related respiratory, neurology, and learning disability services was performed. This was followed by an investigation of relevant sources to identify the potential side effects of these medications. One side effect, namely, xerostomia, which our investigations revealed could be a side effect of 24.8% of the medications used at our institution, was further investigated. The prevalence of xerostomia was then investigated in a randomly selected sample of ten subjects whose dysphagia had been confirmed by videofluoroscopy. It was found that six of the ten dysphagic clients displayed xerostomia. Review of the medications of these ten subjects indicated that all were using from three to nine drugs that could cause xerostomia. This article highlights the need for health-care professionals to consider the potential effects of these medications on swallowing and, indeed, the general presentation of clients.

Effects of Divided Attention on Swallowing in Healthy Participants

Swallowing impairments are treated mostly behaviorally. It is requisite to understand the relationship of cognition, specifically attention, with swallowing since so many swallowing impairments occur concomitantly with cognitive disorders. This study examined the hypothesis that attentional resources are required during swallowing. The approach involved a dual-task, reaction time (RT) paradigm in ten healthy, nonimpaired participants. Baseline measures were obtained of the duration of the anticipatory phase and of the oropharyngeal phase of swallowing and the RTs to nonword auditory stimuli. A dual-task then required participants to swallow 5?ml of water from an 8-oz. cup while listening for a target nonword presented auditorily during the anticipatory or the oropharyngeal phase. Target stimuli were randomized across baseline and dual-task trials. Duration of the anticipatory phase and of the oropharyngeal phase of swallowing and duration of the RT baseline trial and of the dual-task trial were determined. Results showed a statistically significant increase in speed of the anticipatory phase, relative to the oropharyngeal phase, for swallowing during the dual-task. RTs were slowed for both the anticipatory and the oropharyngeal phase during the dual-task, although neither of these was statistically significant. Clinical implications of these data suggest that disruptive stimuli in the environment to nonimpaired individuals may alter feeding but have little effect on the oropharyngeal swallow.     

Objective Measures of Swallowing Function Applied to the Dysphagia Population: A One Year Experience

Quantitative, reliable measures of swallowing physiology can be made from an modified barium swallowing study. These quantitative measures have not been previously employed to study large dysphagic patient populations. The present retrospective study of 139 consecutive patients with dysphagia seen in a university tertiary voice and swallowing clinic sought to use objective measures of swallowing physiology to (1) quantify the most prevalent deficits seen in the patient population, (2) identify commonly associated diagnoses and describe the most prevalent swallowing deficits, and (3) determine any correlation between objective deficits and Eating Assessment Tool (EAT-10) scores and body mass index. Poor pharyngeal constriction (34.5 %) and airway protection deficits (65.5 %) were the most common swallowing abnormalities. Reflux-related dysphagia (36 %), nonspecific pharyngeal dysphagia (24 %), Parkinson disease (16 %), esophageal abnormality (13 %), and brain insult (10 %) were the most common diagnoses. Poor pharyngeal constriction was significantly associated with an esophageal motility abnormality (p < 0.001) and central neurologic insult. In general, dysphagia symptoms as determined by the EAT-10 did not correlate with swallowing function abnormalities. This preliminary study indicates that reflux disease is common in patients with dysphagia and that associated esophageal abnormalities are common in dysphagic populations and may be associated with specific pharyngeal swallowing abnormalities. However, symptom scores from the EAT-10 did not correspond to swallowing pathophysiology.     

Acute Alcohol Intoxication: Sex Comparisons on Pharmacokinetic and Mood Measures

This study explored sex differences in pharmacokinetic and mood state responses to acute alcohol intoxication among socially drinking women demonstrated to be normally cycling across two consecutive menstrual cycles and men with similar drinking habits. Subjects were administered moderate or high alcohol doses in six experimental sessions over a 60-day period. Women were tested during the early follicular, ovulatory, and midluteal phases of the cycle, and men were administered alcohol at comparable time intervals. Results showed that men did not differ in alcohol pharmacokinetics across sessions, but women showed significantly shorter elimination times and faster disappearance rates during the midluteal phase of the menstrual cycle compared to the early follicular and ovulatory phases and to their male counterparts. There were no sex or within-group differences in self-reported negative mood states prior to alcohol administration, but women described increased anxiety and depression while intoxicated during the early follicular compared to ovulatory and midluteal phases. Affective responses to intoxication were a complex function of sex, limb of the blood alcohol concentration-time curve, and dose.     

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.     

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.