Can protein-calorie malnutrition cause dysphagia?

Nutrient deprivation has previously been shown to cause alterations in muscle and nerve function. Although an effect has never been studied in the neuromusculature of deglutition, the authors argue that an effect is likely. The proposed result is an increase in swallowing impairment in dysphagic individuals and associated risk of aspiration. Research studying the relationship between malnutrition and dysphagia is needed to verify clinical significance. Until controlled studies are completed, the authors suggest alternative alimentation in repleting severely malnourished dysphagic patients prior to attempting oral diet. A review of nutritional status indices is included to aid in identifying dysphagic patients at nutritional risk. Early identification of nutritional compromise and intervention can prevent malnutrition and its deleterious effects.     

Chewing and Food Consistency: Effects on Bolus Transport and Swallow Initiation

Preswallow bolus formation usually occurs in the mouth for liquids and in the oropharynx for solid foods. We examined the effect of chewing on the relationship between bolus transport and swallow initiation. Fifteen healthy subjects were imaged with lateral projection videofluorography while eating liquids, solid foods, and a mixture of liquid and solid foods in upright and facedown postures. Videotapes were reviewed to measure the location of the leading edge of the barium at swallow initiation. Chewing and initial consistency each altered the relationship between food transport and swallow initiation. In particular, when chewing liquid (or consuming foods with both liquid and solid phases), a portion of the food commonly reached the hypopharynx well before swallow onset. This transport to the hypopharynx was highly dependent on gravity, but transport to the valleculae for chewed solid food was active, depending primarily on tongue-palate contact. Chewing appeared to reduce the effectiveness of the posterior tongue-palate seal, allowing oral contents to spill into the pharynx. Consuming two-phase foods with both solid and liquid phases may increase the risk of aspiration in dysphagic individuals with impaired airway protective reflexes.     

Developing a dysphagia program in an acute care hospital: A needs assessment

A needs assessment for a hospital-based dysphagia program was conducted to determine incidence, management procedures, and outcome for stroke patients with swallowing disorders. Using a chart review of 225 patients, it was found that 28% had documented evidence of dysphagia. When dysphagia co-occurred with stroke, significantly more functional problems and medical complications were reported, as well as increased need for dietary modifications and alternative feeding methods. The dysphagic patients were more often aphasic and dysarthric and less able to communicate. Mental status was more likely to be reduced and the need for staff supervision during mealtime was increased. Dysphagic patients had significantly longer hospital stays, thus increasing the cost of their care. At discharge, almost half of them continued to need feeding modifications, which may have delayed rehabilitation or transfer to facilities with other levels of care. The dysphagia group clearly displayed a wide range of clinical symptoms that would alert staff to their risk for medical complications because of swallowing problems. We believe that this needs assessment clearly showed that a multidisciplinary dysphagia management program has the potential to enhance patient care while decreasing the cost of health care delivery for the hospital.     

Coordination of mastication and swallowing

The coordination of mastication, oral transport, and swallowing was examined during intake of solids and liquids in four normal subjects. Videofluorography (VFG) and electromyography (EMG) were recorded simultaneously while subjects consumed barium-impregnated foods. Intramuscular electrodes were inserted in the masseter, suprahyoid, and infrahyoid muscles. Ninety-four swallows were analyzed frame-by-frame for timing of bolus transport, swallowing, and phases of the masticatory gape cycle. Barium entered the pharynx a mean of 1.1 s (range −0.3 to 6.4 s) before swallow onset. This interval varied significantly among foods and was shortest for liquids. A bolus of food reached the valleculae prior to swallow onset in 37% of sequences, but most of the food was in the oral cavity at the onset of swallowing. Nearly all swallows started during the intercuspal (minimum gape) phase of the masticatory cycle. Selected sequences were analyzed further by computer, using an analog-to-digital convertor (for EMG) and frame grabber (for VFG). When subjects chewed solid food, there were loosely linked cycles of jaw and hyoid motion. A preswallow bolus of chewed food was transported from the oral cavity to the oropharynx by protraction (movement forward and upward) of the tongue and hyoid bone. The tongue compressed the food against the palate and squeezed a portion into the pharynx one or more cycles prior to swallowing. This protraction was produced by contraction of the geniohyoid and anterior digastric muscles, and occurred during the intercuspal (minimum gape) and opening phases of the masticatory cycle. The mechanism of preswallow transport was highly similar to the oral phase of swallowing. Alternation of jaw adductor and abductor activity during mastication provided a framework for integration of chewing, transport, and swallowing.     

Dysphagia following strokes: Clinical observations of swallowing rehabilitation employing Palatal Training Appliances

A retrospective study was undertaken to evaluate the progress of a group of dysphagic stroke patients for whom a dental prosthesis the Palatal Training Appliance (PTA), was used in the active rehabilitation of the swallowing mechanism. Patients selected were those who had sustained a stroke uncomplicated by other neurological illness, during one 12-month period, and whose dysphagia caused anxiety to the medical staff in the hospital ward. Thirty severely dysphagic stroke patients satisfied these criteria. The study recorded the duration and type of supplementary feeding required during hospitalization. Thirteen patients had evidence of aspiration before the PTA was fitted and 5 afterwards. Seven patients died, but only 1 was recorded as having a febrile illness which may have contributed to the death. At discharge, which averaged 10 weeks after admission, 22 of the 23 survivors were taking an adequate oral diet. It was also noted that almost half of the patients who wore dentures before the cerebrovascular event were unable to control them afterwards, adding to their neurological swallowing difficulties. The fitting of a PTA and correction of unstable dentures appeared to help both motivation and function. The results show an improvement in the rehabilitation of oral feeding compared with previous reports by other authors, who did not use the dental appliance. There did not appear to be any medical contraindication to its use.     

Decreased Tongue Pressure Reflects Symptom of Dysphagia

The tongue plays a key role in oropharyngeal swallowing. It has been reported that maximum isometric tongue pressure decreases with age. The risk for dysphagia resulting from low tongue strength remains unclear. This study was designed to reveal the relationship between tongue pressure and clinical signs of dysphagic tongue movement and cough and to demonstrate the clinical value of tongue pressure measurement in the evaluation of swallowing function. One hundred forty-five institutionalized elderly in five nursing homes participated. Evaluation of physical activity with self-standing up capability and mental condition with Mini Mental Status Examination (MMSE) were recorded. Maximum tongue pressure was determined using a newly developed tongue pressure measurement device. Voluntary tongue movement and signs of dysphagic cough at mealtime were inspected and evaluated by one clinically experienced dentist and speech therapist. The relationship between level of tongue pressure and incidence of cough was evaluated using logistic regression analysis with physical and mental conditions as covariates. Tongue pressure as measured by the newly developed device was significantly related to the voluntary tongue movement and incidence of cough (p < 0.05). The results of this study suggest that tongue pressure measurement reflects clinical signs of dysphagic tongue movement and cough and that measurement of tongue pressure is useful for the bedside evaluation of swallowing.This study was supported by a grant-in-aid from the Ministry of Health, Labour and Welfare (tyoujyu-14-020).     

The Effects of Cervical Bracing Upon Swallowing in Young,Normal, Healthy Volunteers

Abstract The purpose of this study was to evaluate radiographically the effects of cervical bracing upon swallowing thin liquids and solid food in normal adults under three cervical bracing conditions. This was a prospective, repeated measures design study. Seventeen healthy adult volunteers between the ages of 30 and 50 were recruited from hospital staff. All subjects reported no previous history of swallowing difficulty or diseases that might affect swallowing. Subjects were radiographically observed swallowing thin liquids and solid food without cervical bracing and with three common cervical orthoses (Philadelphia collar, SOMI, and halo-vest brace). Order of bracing and type of bolus were randomized. Changes in swallowing function (point of initiation of swallow response, presence of pharyngeal residue, airway penetration, hyoid bone movement, diameter of oropharyngeal airway, and durational measurements) were analyzed by two independent raters. Eighty-two percent (14/17) of the subjects demonstrated radiographic changes under one or more of the bracing conditions. Forty-seven percent (8/17) of subjects demonstrated changes with point of initiation of the swallow response, 59% (10/17) demonstrated increased pharyngeal residue, and 23.5% (4/17) demonstrated changes with bolus flow with laryngeal penetration present. Aspiration did not occur under any of the bracing conditions. Changes noted in durational measurements for oral containment and total pharyngeal transit under the bracing conditions were not considered statistically significant. This study shows that cervical bracing does change swallowing physiology in normal healthy adults.     

Reliability and Validity of Cervical Auscultation

We conducted a two-part study that contributes to the discussion about cervical auscultation (CA) as a scientifically justifiable and medically useful tool to identify patients with a high risk of aspiration/penetration. We sought to determine (1) acoustic features that mark a deglutition act as dysphagic; (2) acoustic changes in healthy older deglutition profiles compared with those of younger adults; (3) the correctness and concordance of rater judgments based on CA; and (4) if education in CA improves individual reliability. The first part of the study focused on a comparison of the "swallow morphology" of dysphagic as opposed to healthy subjects' deglutition in terms of structure properties of the pharyngeal phase of deglutition. We obtained the following results. The duration of deglutition apnea is significantly higher in the older group than in the younger one. Comparing the younger group and the dysphagic group we found significant differences in duration of deglutition apnea, onset time, and number of gulps. Just one parameter, number of gulps, distinguishes significantly between the older and the dysphagic groups. The second part of the study aimed at evaluating the reliability of CA in detecting dysphagia measured as the concordance and the correctness of CA experts in classifying swallowing sounds. The interrater reliability coefficient AC1 resulted in a value of 0.46, which is to be interpreted as fair agreement. Furthermore, we found that comparison with radiologically defined aspiration/penetration for the group of experts (speech and language therapists) yielded 70% specificity and 94% sensitivity. We conclude that the swallowing sounds contain audible cues that should, in principle, permit reliable classification and view CA as an early warning system for identifying patients with a high risk of aspiration/penetration; however, it is not appropriate as a stand-alone tool.     

Effect of Liquid Bolus Consistency and Delivery Method on Aspiration and Pharyngeal Retention in Dysphagia Patients

There is no empirically derived consensus as to what food consistency types and method of food delivery (spoon, cup, straw) should be included in the videofluoroscopic swallowing (VFSS) studies. In the present study, we examine the rates of aspiration and pharyngeal retention in 190 dysphagic patients given thin (apple juice) and thick (apricot nectar) liquids delivered by teaspoon and cup and ultrathick (pudding-like) liquid delivered by teaspoon. Each patient was tested with each of the bolus/delivery method combinations. The fractions of patients exhibiting aspiration for each bolus/method of delivery combination were (1) thick liquids (cup), 13.2%; (2) thick liquids (spoon), 8.9%; (3) thin liquids (cup), 23.7%; (4) thin liquids (spoon), 15.8%, (5) ultrathick liquids (spoon), 5.8%. In each comparison [thick liquid (cup) vs. thick liquid (spoon), thin liquid (cup) vs. thin liquid (spoon), thick liquid (cup) vs. thin liquid (cup), thick liquid (spoon) vs. thin liquid (spoon), and thick liquid (spoon) vs. ultrathick liquid (spoon)], the p value for χ² was <0.001. These results suggest that utilizing thin, thick, and ultrathick liquids and delivery by cup and spoon during a VFSS of a patient with mild or moderate dysphagia can increase the chances of identifying a consistency that the patient can swallow without aspirating and without pharyngeal retention after swallowing. Submitted December 22, 1999; accepted September 6, 2000 with revision     

Dynamics of Capsule Swallowing by Healthy Young Men and Capsule Transit Time from the Mouth to the Stomach

We examined the dynamics of capsule swallowing by healthy young men using the anterior-posterior view of videofluoroscopy as a first step in a study on capsule swallowing by dysphagic patients. The subjects were 14 healthy men who did not have any complaint of dysphagia. They were asked to swallow a #4 hard gelatin capsule filled with barium sulfate with 15 ml of water during the videofluoroscopic examination. This examination was repeated three times for each subject (total of 42 trials). In four of the 14 subjects, a swallowed capsule was retained at the upper esophageal sphincter, or the broncho-aortic constriction of the esophagus, or the lower esophageal sphincter. Except where retention occurred, the average capsule transit time from the mouth to the stomach was 6.0 ± 2.4 s. Three of the four subjects who had capsule retention did not realize that the swallowed capsule was retained en route to the stomach. By considering the dynamics of swallowing a capsule with 15 ml of water in healthy men, we should be able to reveal the dynamics of capsule swallowing in dysphagic patients, and the capsule transit time from the mouth to the stomach.     

Influences of Thermal and Gustatory Characteristics on Sensory and Motor Aspects of Swallowing

Two sets of experiments were conducted to examine the effects of two sensory modalities, temperature and taste, of foods on perceptual and motor aspects of swallowing in 20 young, healthy subjects (10 subjects for each experiment). A tasteless and odorless thickening agent was the basic testing material. The first experiment compared the swallowing of foods at four temperatures ranging from 5°C to 50°C. Food at 50°C was more acceptable for swallowing than at 5°C, 20°C, or 35°C. The suprahyoid muscles were less active during swallowing food at 50°C compared with swallowing food at the other three temperatures. The second experiment compared foods with the five basic taste qualities (sweetness, saltiness, sourness, bitterness, and umami) with a tasteless food (dissolved in distilled water) to examine the influence of gustatory sensation. The sweet and tasteless foods were somewhat more acceptable for swallowing than the sour and bitter foods. However, none of the foods differentially altered the motor parameters of swallowing. Interactive influences of temperature and gustatory sensations of foods on swallowing are discussed.     

Oral function test for monitoring suction and swallowing in the neurologic patient

Disturbances in swallowing are common in neurologic disease but difficult to evaluate in the clinical setting. Fundamental variables such as bolus volume, swallow capacity (volume ingested over time), and the relation between ingestion and time for important events in oral and pharyngeal swallowing have not been sufficiently studied. We therefore employed a composite method for monitoring oral and pharyngeal swallowing function: the test of Repetitive Oral Suction Swallow (the ROSS test). The technical details are described as well as preliminary results from a pilot study of 20 healthy subjects and 5 patients with neurologic swallowing impairment. The correlation with respect to time sequences for major events in bolus ingestion and oral processing as monitored by the ROSS test and by videoradiography is explained. With this simple and rapid bedside test, the immediate and long-time result of therapeutic interventions in dysphagic patients may be monitored.     

Thermal application reduces the duration of stage transition in dysphagia after stroke

The present study had two purposes. The first was to provide variability data on objectively measured durational parameters of swallowing as accomplished by dysphagic patients secondary to stroke. The second was to examine the short-term effects of thermal application on these same durational measures. The study employed a cross-over design with each dysphagic stroke subject swallowing 10 times in both untreated and treated conditions. Two findings emerged: (1) swallowing durations in the 22 dysphagic stroke subjects were highly variable within and across subjects and have distributions that were nonnormal with nonhomogeneous variances; (2) thermal application reduced duration of stage transition (DST) and total swallow duration (TSD). Implications of these findings are discussed.This work was performed at the William S. Middleton Memorial Veterans Hospital; Madison, WisconsinThis is publication number 95-10 of the Madison Geriatrics Research Education and Clinical Center     

Promoting Safe Swallowing When Puree is Swallowed Without Aspiration but Thin Liquid is Aspirated: Nectar is Enough

The use of thickened liquids is a common compensatory strategy to improve swallow safety. The purpose of this study was to determine the optimal liquid viscosity to use to promote successful swallowing in a specific subset of dysphagic patients who swallow puree without aspiration but thin liquid with aspiration. A referral-based sample of 84 consecutive inpatients from a large, urban, tertiary-care teaching hospital who met the study criteria was analyzed prospectively. Inclusion criteria were no preexisting dysphagia, a successful pharyngeal swallow without aspiration with puree consistency but pharyngeal dysphagia with aspiration of thin liquid consistency, and stable medical, surgical, and neurological status at the time of transnasal fiberoptic swallow testing and up to 24 h after recommendations for oral alimentation with a modified diet consisting of nectar-like and honey-like thickened liquids. Success with ingesting both nectar-like and honey-like thickened liquids and clinically evident aspiration events were recorded. Care providers were blinded to the study’s purpose. All 84 patients were successfully ingesting nectar-like and honey-like thickened liquids at the time of swallow testing and up to 24 h after testing. A specific subset of dysphagic patients who swallowed puree without aspiration but aspirated thin liquid demonstrated 100 % successful swallowing of both nectar-like and honey-like thickened liquids. Therefore, a nectar-like thickened liquid appears to be adequate to promote safe swallowing in these patients and, because of patient preference for the least thick liquid, may enhance compliance and potentially contribute to maintenance of adequate hydration requirements.     

Symmetry and reproducibility of swallowing sounds

Cervical auscultation is being used more frequently in the clinical assessment of dysphagic patients. The present study was designed to assess symmetry and the reproducibility of swallowing sounds detected simultaneously from bilateral cervical sites. Symmetry of the swallowing sounds acquired using our method was verified because no significant differences were found for any parameters in both time and frequency domain analyses between swallowing sounds detected bilaterally. This result supports the use of a unilateral site for the detection of swallowing sounds. The reproducibility of swallowing sounds was assessed by a coefficient of variation. Results of this analysis suggest that one should evaluate the acoustic characteristics of swallowing sounds from repeated swallows rather than from one swallow.     

Modified barium swallow: clinical and radiographic correlation and relation to feeding recommendations

Clinical and videofluoroscopic evaluation of swallowing were correlated to determine their agreement and relationship to feeding recommendations. We reviewed a total of 148 patients with swallowing difficulties, of which 93 (45 women, 48 men; mean age 62 years) were evaluated by both clinical and radiographic examinations. A variety of materials were used for clinical bedside evaluation of oral and pharyngeal function. Radiographic examination was done with variable viscosity materials and videotape recording of the oral cavity and pharynx. The severity of oral and pharyngeal abnormalities was graded and findings of the examinations were compared. The combined results of both evaluations generated an index of swallowing difficulty which was correlated to the type of diet used if oral feeding was recommended or to a nonoral route of nutrition. In the assessment of oral and pharyngeal dysfunction, clinical evaluation and radiographic examination correlated closely in 94% of patients; however, the status of pharyngeal function was not determined in 61 (66%) of the 93 patients by clinical examination alone. The combined swallowing index was calculated in 89 patients and its severity correlated significantly with the type of feeding recommended; 64 patients were placed on one of three types of diets and 25 had enteral feedings. In conclusion, combined clinical and radiographic examinations correlated well, but clinical evaluation alone was limited by failure to evaluate the pharynx in many patients. The swallowing severity correlated well with final feeding recommendations.     

Evaluating Oral Stimulation as a Treatment for Dysphagia after Stroke

Deglutitive aspiration is common after stroke and can have devastating consequences. While the application of oral sensory stimulation as a treatment for dysphagia remains controversial, data from our laboratory have suggested that it may increase corticobulbar excitability, which in previous work was correlated with swallowing recovery after stroke. Our study assessed the effects of oral stimulation at the faucial pillar on measures of swallowing and aspiration in patients with dysphagic stroke. Swallowing was assessed before and 60 min after 0.2-Hz electrical or sham stimulation in 16 stroke patients (12 male, mean age = 73 ± 12 years). Swallowing measures included laryngeal closure (initiation and duration) and pharyngeal transit time, taken from digitally acquired videofluoroscopy. Aspiration severity was assessed using a validated penetration-aspiration scale. Preintervention, the initiation of laryngeal closure, was delayed in both groups, occurring 0.66 ± 0.17 s after the bolus arrived at the hypopharynx. The larynx was closed for 0.79 ± 0.07 s and pharyngeal transit time was 0.94 ± 0.06 s. Baseline swallowing measures and aspiration severity were similar between groups (stimulation: 24.9 ± 3.01; sham: 24.9 ± 3.3, p = 0.2). Compared with baseline, no change was observed in the speed of laryngeal elevation, pharyngeal transit time, or aspiration severity within subjects or between groups for either active or sham stimulation. Our study found no evidence for functional change in swallow physiology after faucial pillar stimulation in dysphagic stroke. Therefore, with the parameters used in this study, oral stimulation does not offer an effective treatment for poststroke patients.Abbreviations: mA = milliamps; FP = faucial pillar; LCD = laryngeal closure duration; OTT = oral transit time; PTT = pharyngeal transit time; SRT = swallow response time; TMS = transcranial magnetic stimulation; UES = upper esophageal sphincter.     

Pharyngeal constrictor paresis: An indicator of neurologic disease?

Pharyngeal constrictor paresis (PHCP) is sometimes found in videoradiography of the swallowing act in patients complaining of dysphagia. Ten patients with PHCP and 10 dysphagic, age- and sex-matched controls with normal videoradiography were neurologically evaluated and examined with magnetic resonance imaging (MRI) of the brain and brainstem in order to learn the pathogenetic process behind PHCP. The study revealed 8 PHCP patients and 1 dysphagic control with abnormal clinical neurological findings such as myopathy, cerebrovascular disease, or extrapyramidal disease. The neurological examination revealed considerable information of prognostic and therapeutic value in PHCP patients. The MRI was abnormal in 7 PHCP patients and 4 dysphagic controls. However, the findings in MRI were nonspecific but the examination was found to be valuable in selected cases. It is concluded that PHCP is an indicator of neurological disease and accordingly, such patients should be examined by a neurologist to establish the cause of the disease.     

Clinical Variables Associated with Hydration Status in Acute Ischemic Stroke Patients with Dysphagia

Acute stroke patients with dysphagia are at increased risk for poor hydration. Dysphagia management practices may directly impact hydration status. This study examined clinical factors that might impact hydration status in acute ischemic stroke patients with dysphagia. A retrospective chart review was completed on 67 ischemic stroke patients who participated in a prior study of nutrition and hydration status during acute care. Prior results indicated that patients with dysphagia demonstrated elevated BUN/Cr compared to non-dysphagia cases during acute care and that BUN/Cr increased selectively in dysphagic patients. This chart review evaluated clinical variables potentially impacting hydration status: diuretics, parenteral fluids, tube feeding, oral diet, and nonoral (NPO) status. Exposure to any variable and number of days of exposure to each variable were examined. Dysphagia cases demonstrated significantly more NPO days, tube fed days, and parenteral fluid days, but not oral fed days, or days on diuretics. BUN/Cr values at discharge were not associated with NPO days, parenteral fluid days, oral fed days, or days on diuretics. Patients on modified solid diets had significantly higher mean BUN/Cr values at discharge (27.12 vs. 17.23) as did tube fed patients (28.94 vs. 18.66). No difference was noted between these subgroups at baseline (regular diet vs. modified solids diets). Any modification of solid diets (31.11 vs. 17.23) or thickened liquids (28.50 vs. 17.81) resulted in significantly elevated BUN/Cr values at discharge. Liquid or diet modifications prescribed for acute stroke patients with dysphagia may impair hydration status in these patients.     

Effectiveness of Computer-Based Dysphagia Training for Direct Patient Care Staff

Speech–language pathologists (SLPs) in medical settings are responsible for evaluating patients’ feeding and swallowing. Once an evaluation is completed, nursing staff typically provides hands-on care and supervision of meals. SLPs seek to improve outcomes for individuals with dysphagia by educating direct-care staff. This project sought to determine whether a computer-based swallowing safety module could produce changes in knowledge levels of nursing staff. This module was designed to replace inservices conducted by staff SLPs. Nursing staff would be required to complete the training when hired and as an annual assessment. The training module was designed and pilot-tested along with a pre- and posttest to assess changes in knowledge. Participants in the experimental group took the pretest, completed the computer training module, and then took the posttest. Participants in the control group took the pre- and posttest with no intervening training. Statistically significant differences were found between the two groups on posttest scores. Participants in the experimental group demonstrated increased test scores, while the scores of the control group did not change significantly. This study indicates that computer-based training for nursing staff related to swallowing safety and dysphagia is effective.