Aspiration and the elderly

The fluid mechanics of bolus ejection from the oral cavity

The squeezing action of the tongue against the palate provides driving forces to propel swallowed material out of the mouth and through the pharynx. Transport in response to these driving forces, however, is dependent on the material properties of the swallowed bolus. Given the complex geometry of the oral cavity and the unsteady nature of this process, the mechanics governing the oral phase of swallowing are not well understood. In the current work, the squeezing flow between two approaching parallel plates is used as a simplified mathematical model to study the fluid mechanics of bolus ejection from the oral cavity. Driving forces generated by the contraction of intrinsic and extrinsic lingual muscles are modeled as a spatially uniform pressure applied to the tongue. Approximating the tongue as a rigid body, the motion of tongue and fluid are then computed simultaneously as a function of time. Bolus ejection is parameterized by the time taken to clear half the bolus from the oral cavity, t(1/2). We find that t(1/2) increases with increased viscosity and density and decreases with increased applied pressure. In addition, for low viscosity boluses (mu approximately 100 cP), density variations dominate the fluid mechanics while for high viscosity boluses (mu approximately 1000 cP), viscosity dominates. A transition region between these two regimes is found in which both properties affect the solution characteristics. The relationship of these results to the assessment and treatment of swallowing disorders is discussed.

Interventions to prevent pneumonia among older adults

Pneumonia is a common cause of death in older people. Antimicrobial drugs do not prevent pneumonia and, because of increasingly resistant organisms, their value in curing infection will become more limited. Establishing new strategies to prevent pneumonia through consideration of the mechanisms of this devastating illness is essential. The purpose of this review is to discuss how pneumonia develops in older people and to suggest preventive strategies that may reduce the incidence of pneumonia among older adults. Aspiration of oropharyngeal bacterial pathogens to the lower respiratory tract is one of the most important risk factors for pneumonia; impairments in swallowing and cough reflexes among older adults, e.g., related to cerebrovascular disease, increase the risk for the development of pneumonia. Thus, strategies to reduce the volumes and pathogenicity of aspirated material should be pursued. For example, since both swallowing and cough reflexes are mediated by endogenous substance P, pharmacologic therapy using angiotensin-converting enzyme inhibitors, which decrease substance P catabolism, may improve both reflexes and result in the lowering of the risk of pneumonia. Similarly, since the production of substance P is regulated by dopaminergic neurons in the cerebral basal ganglia, treatment with dopamine analogs or potentiating drugs such as amantadine (and, of course, prevention of cerebral vascular disease, which can result in basal ganglia strokes) should affect the incidence of pneumonia. The purpose of this review is to consider promising pharmacologic treatments as methods of preventing pneumonia in older adults and to review other proven strategies, e.g., infection control and cerebrovascular disease prevention that will lessen the incidence of pneumonia.

Age effects on the temporal evolution of isometric and swallowing pressure

BACKGROUND

The tongue plays a key role in bolus propulsion through the oropharyngeal chamber. In this study, possible age effects on the magnitude and timing of lingual pressure generation were analyzed.

METHODS

Oral pressure was measured during isometric and swallowing tasks for 10 elderly (mean age = 81 years) and 10 young (mean age = 51 years) subjects. Three trials each of the isometric task and swallows of three different boluses (3 ml semisolid, 3 ml liquid, and 10 ml liquid) were performed by each subject. The timing and magnitude of isometric and swallowing pressure generation along with the pattern of the swallowing pressure waveform were analyzed.

RESULTS

Whereas maximum lingual isometric pressures decreased with age (p < .001). no significant age difference was found for swallowing pressure. Time taken to reach peak pressure also was reduced with age in both the isometric task and swallows of liquid boluses (p < .05), while no significant age effect was found for semisolid swallows. Finally, only elderly subjects showed a pattern of liquid swallowing pressure generation in which multiple lingual gestures were required to reach peak pressure (termed "pressure building"), a pattern demonstrated by both young and elderly groups for semisolids.

CONCLUSIONS

Decreased lingual strength with age combined with unchanging swallowing pressure leads to a decreased "pressure reserve," perhaps leaving older individuals more at risk for dysphagia resulting from insults directly or indirectly to the swallowing system. Additionally, swallowing is generally "slowed" with age, apparently due to both central and peripheral factors, and this change may have an impact on bolus flow outcomes.

Detection of aspiration and swallowing disorder in older stroke patients: simple swallowing provocation test versus water swallowing test

OBJECTIVE

To assess the sensitivity and specificity of a simple swallowing provocation test (SPT) and a water swallowing test (WST) in detecting aspiration pneumonia in elderly patients with stroke.

DESIGN

Retrospective comparative study involving a simple 2-step SPT and WST on all subjects.

PARTICIPANTS

Twenty-six stroke patients with aspiration pneumonia (mean age, 72.1 +/- 4.1 yr) and 26 age-matched stroke patients without aspiration pneumonia (mean age, 69.4 +/- 3.9 yr).

INTERVENTIONS

The normal response to SPT was determined by inducing swallowing reflex within 3 seconds after water injection into the suprapharynx. In WST, subjects drank quantities of 10 and 30 mL of water from a cup within 10 seconds. The subject who drank water without interruption-without evidence of aspiration-was determined as normal.

RESULTS

The sensitivity and specificity of first-step SPT for the detection of aspiration pneumonia were 100% and 83.8%, respectively. Those of the second-step SPT were 76.4% and 100%, respectively. The sensitivity and specificity of first-step WST using 10 mL of water for the detection of aspiration pneumonia were 71.4% and 70.8%, respectively. Those of the second-step WST using 30 mL of water were 72% and 70.3%, respectively.

CONCLUSION

SPT is more useful than WST in differentiating patients predisposed to aspiration.

Relation between incidence of pneumonia and protective reflexes in post-stroke patients with oral or tube feeding

OBJECTIVES

Although attenuated protective reflexes have been implicated in the development of aspiration pneumonia, the relation between the incidence of pneumonia and the state of these reflexes has not been investigated. Furthermore, the role of feeding tube placement in preventing pneumonia in patients with attenuated protective reflexes is unknown. We studied the relationship between the incidence of pneumonia and the state of cough and swallowing reflexes in post-stroke patients with oral or tube feeding.

DESIGN

The incidence of pneumonia was prospectively analysed for 1 year in three groups of post-stroke patients on the basis of the following clinical conditions: oral feeding without dysphagia (n = 43); oral feeding with dysphagia (n = 48); and nasogastric tube feeding with dysphagia (n = 52). We also studied the incidence of pneumonia in bedridden patients with nasogastric tube feeding (n = 14). Before the start of the study, the swallowing and cough reflexes of each patient were measured. The swallowing reflex was evaluated according to latency of response, which was timed from the injection of 1 mL of distilled water into the pharynx through a nasal catheter to the onset of swallowing. The cough threshold of citric acid aerosols was defined as the concentration at which the patient coughed five times. RESULTS.;: The incidence of pneumonia was observed in patients having both a latency of response longer than 5 s and a cough threshold for citric acid higher than a concentration of 1.35 (log mg mL-1). The incidence of pneumonia was significantly higher in patients with oral feeding than in those with tube feeding (54.3 vs. 13.2%, P < 0.001). In bedridden patients with tube feeding, the latency of response was longer than 20 s and no patient coughed at the highest concentration of citric acid. The incidence of pneumonia was 64.3% in such patients.

CONCLUSIONS

The state of protective reflexes had a significant relation to the incidence of pneumonia. Feeding tube placement may have a beneficial role in preventing aspiration pneumonia in mildly or moderately disabled post-stroke patients with attenuated protective reflexes. Bedridden patients who were tube-fed had the highest incidence of pneumonia.

Impaired swallowing reflex in patients with obstructive sleep apnea syndrome

BACKGROUND

The swallowing reflex is well coordinated with breathing patterns in normal humans. However, patients with obstructive sleep apnea syndrome (OSAS) may have a swallowing disorder that reflects the abnormal function of nerves and muscles in the suprapharynx.

OBJECTIVE

To examine the relationship between the swallowing function and sleep-disordered breathing in patients with OSAS.

PARTICIPANTS

Twenty patients with OSAS with a mean (+/-SD) age of 53.4+/-8.9 years old, and 20 age-matched control subjects with a mean age of 51.4+/-9.1 years old.

METHODS

OSAS was diagnosed using the recordings of overnight polysomnography. The swallowing function in the subject was tested using a swallowing provocation test. The swallowing reflex was determined according to the following criteria: latent time (LT), the time following a bolus injection of distilled water at the suprapharynx to the onset of swallowing; inspiratory suppression time (IST), the time from the termination of swallowing to the next onset of inspiration; and threshold volume, the minimum volume of water (range, 0.4 to 2 mL) that could evoke the swallowing response.

RESULTS

Whereas the LT values in patients with OSAS were larger than the LT values in the control subjects, the IST values (which may reflect the switching mechanism from deglutition apnea to breathing) were actually shorter. In addition, a greater bolus volume was necessary to elicit swallowing in patients with OSAS than was necessary in the control subjects.

CONCLUSION

Patients with OSAS are likely to exhibit an impaired swallowing reflex, probably due to the perturbed neural and muscular function of the upper airways.

Vagal esophageal receptors in anesthetized dogs: mechanical and chemical responsiveness

This study was performed to evaluate the characteristics of esophageal receptors in anesthetized and artificially ventilated dogs. The electrical activity of the esophageal afferents was recorded from the peripheral cut end of the cervical vagus nerve. A cuffed catheter was inserted into the esophagus at the level of the third tracheal ring and was used to establish the esophageal location of the endings. Most of the receptors were localized in the intrathoracic portion of the esophagus. The majority of the receptors studied (36 of 43) showed a slow adaptation to a maintained stretch of the esophageal wall. Vagal cooling blocked receptor activity at temperatures ranging from 3.5 to 25 degrees C. Twenty-eight of 43 receptors, including 4 rapidly adapting endings (RAR), were challenged with saline, HCl + pepsin (HCl-P; pH 1) and distilled water (8 ml, 37 degrees C). HCl-P solutions specifically stimulated only three receptors; saline or water did not. Five slowly adapting receptors and two RARs were also challenged with topically applied capsaicin; only one RAR was stimulated. To ascertain a possible effect of smooth muscle contraction, 17 receptors were tested with intravenous injections of ACh and/or asphyxia; only 4 were stimulated. These characteristics do not support an important reflexogenic role of the esophagus in response to chemical stimuli.

Dysphagia among nursing home residents

As part of a larger study that investigated the social, cultural, clinical, and environmental factors that influenced nutritional intake in two proprietary nursing homes, 82 of 100 residents who were not eating well received a bedside dysphagia screening evaluation by a speech pathologist. This article reports on the dysphagia evaluation results and the consequences of swallowing disorders for nursing home residents. Forty-five of the 82 residents (55%) had some degree of dysphagia, ranging from mild to profound, but only 10 of these 45 residents (22%) had been referred for a dysphagia evaluation. Unrecognized and unmanaged dysphagia may lead to dehydration, malnutrition, aspiration pneumonia, and asphyxiation. Assessment and management of dysphagia also are discussed.

Investigation of effects of anesthesia and age on aspiration in mice through LacZ gene transfer by recombinant E1-deleted adenovirus vectors

To examine the role of disturbed upper airway reflexes in aspiration, we administered 20 microliters of the adenovirus (Ad) vector Ad-CMV-LacZ or 20 microliters of phosphate buffered saline (PBS) intranasally to C57 black mice. We investigated expression of the LacZ gene by this Ad vector in the nostrils of each mouse, with or without anesthesia. Under anesthesia, LacZ gene expression was detected in the lungs of every mouse given the Ad vector. However, no LacZ gene expression was found in the trachea or lungs of mice given the Ad vector without anesthesia. In mice given PBS or wild-type adenovirus transnasally during anesthesia, there was no LacZ gene expression in the nostrils, trachea, or lungs, suggesting that with 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal) staining, blue-stained cells indicated transferred LacZ gene expression. These results suggested that aspiration of intranasal solution into lower airways was caused by disturbed upper airway reflexes during anesthesia. This process can be analyzed by the distribution of LacZ gene expression in airways. We next examined the effect of age on anesthesia-induced aspiration. Twenty-six-mo-old mice exhibited more LacZ gene expression in their lungs than did 6-mo-old mice at a concentration of 0.5 to 4.0% halothane in 100% oxygen. This suggests that light anesthesia may depress upper airway reflexes and cause aspiration in older animals. This novel model of aspiration, generated with the Ad-CMV-LacZ vector, may be useful for elucidating the mechanism of development of aspiration pneumonia in relation to age-related impairment of upper airway reflexes.

A prospective study of the use of liquid oral dietary supplements in nursing homes

OBJECTIVE

To investigate the use of liquid oral dietary supplements among nursing home residents who were eating poorly and losing weight.

DESIGN

A prospective, descriptive, anthropological study.

SETTING

Two proprietary nursing homes with 105 and 138 beds.

PARTICIPANTS

Purposive sampling was used to select 40 residents from among the 100 residents who were not eating well. Dietary data were collected on this sub-sample of 40 residents.

MEASUREMENTS

Participant observation, in-depth interviews, event analysis, bedside dysphagia screenings, oral health examinations, body weight, body mass index (BMI), and chart review were used to collect data. Dietary data were collected over a 3-day period, and data were gathered on how supplements were ordered, served, and consumed.

RESULTS

Supplements had been ordered for 29 of the subsample of 40 residents. Only nine of 29 residents were served the correct number and type of supplements as ordered by their physicians, and only two residents consumed the full amount of supplement as ordered. The overall mean percentage of supplement consumed compared with that ordered was 55.1%. Although supplements were ordered primarily to prevent weight loss and to facilitate weight gain, nearly half (n = 14) of the residents continued to lose weight. Supplements were ordered without investigating the underlying factors contributing to weight loss, such as inadequate staffing and lack of supervision at mealtime, undiagnosed dysphagia, and poor oral health. Without evaluation of these factors, it is unknown which residents might benefit from oral supplements.

CONCLUSION

Findings indicate that supplements were used nonspecifically as an intervention for weight loss in nursing home residents without regard to dose, diagnosis and management of underlying problem(s), amount of supplement consumed, and outcome. Further research is needed to establish when supplements should be ordered, how to ensure that they will be taken, and whether they are effective.

Effects of HCl-pepsin laryngeal instillations on upper airway patency-maintaining mechanisms

Gastroesophageal reflux has been indicated as an etiopathological factor in disorders of the upper airway. Upper airway collapsing pressure stimulates pressure-responsive laryngeal receptors that reflexly increase the activity of upper airway abductor muscles. We studied, in anesthetized dogs, the effects of repeated laryngeal instillations of HCl-pepsin (HCl-P; pH = 2) on the response of laryngeal afferent endings and the posterior cricoarytenoid muscle (PCA) to negative pressure. The effect of negative pressure on receptor discharge or PCA activity was evaluated by comparing their response to upper airway (UAO) and tracheal occlusions (TO). It is only during UAO, but not during TO, that the larynx is subjected to negative transmural pressure. HCl-P instillation decreased the rate of discharge during UAO of the 10 laryngeal receptors studied from 56.4 +/- 10.9 (SE) to 38.2 +/- 9.2 impulses/s (P < 0.05). With UAO, the peak PCA moving time average, normalized by dividing it by the peak values of esophageal pressure, decreased after six HCl-P trials from 4.29 +/- 0.31 to 2.23 +/- 0.18 (n = 6; P < 0.05). The responses to TO of either receptors or PCA remained unaltered. We conclude that exposure of the laryngeal mucosa to HCl-P solutions, as it may occur with gastroesophageal reflux, impairs the patency-maintaining mechanisms provided by laryngeal sensory feedback. Inflammatory and necrotic alterations of the laryngeal mucosa are likely responsible for these effects.

Mechanisms and prevention of pneumonia in the elderly

Pneumonia is not only a major cause of death for elderly persons, but also imposes substantial personal morbidity and burdens on the health care system. An understanding of the pathogenesis of this serious illness could allow us to devise methods for curbing the incidence and severity of the disease. Pathophysiological issues and preventative measures are the subject of this review.

Dysphagia in the patient with a tracheostomy: six cases of inappropriate cuff deflation or removal

Patients with tracheostomy tubes have altered motor and sensory functions that may decrease their swallowing efficiency. Failure to recognize disorders in deglutition may result in dangerous complications including aspiration and death. Assessment of dysphagia is especially important in the patient transferred from the intensive care unit to the ward--where resources are less abundant. We present six cases in which cuff deflation or change of tracheostomy tube were undertaken without documented swallowing assessment. In these cases each patient was found to be aspirating and required the cuff to be reinflated, or a cuffed tube to be reinstated when assessed by the multidisciplinary team. Dysphagia management in the patient with a tracheostomy should be approached from a multidisciplinary point of view so that appropriate decisions can be made regarding changes in management and the decannulation process.

Dysphagia in elderly men with myasthenia gravis

Eight elderly men whose primary symptoms of myasthenia gravis were decreased speech and swallowing ability were seen for speech pathology evaluations and videofluoroscopic swallow studies. All patients had fatigable flaccid dysarthria and greater than expected pharyngeal phase dysphagia on videofluoroscopy; eight had decreased pharyngeal motility as demonstrated by residual material in the valleculae and pyriform sinuses bilaterally; seven had episodes of laryngeal penetration secondary to overflow of residual material; and five experienced silent aspiration despite gag reflexes and the ability to cough to command. Five patients required feeding tubes because their dysphagia responded poorly to treatment. Videofluoroscopic swallow studies revealed a common swallowing profile with pharyngeal phase dysphagia greater than expected from patient symptoms. Dysphagia did not improve at the same rate as other manifestations of myasthenia gravis.

Natural history of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome) and clinical predictors of survival: a clinicopathological study

OBJECTIVE--To analyse the natural history of progressive supranuclear palsy (PSP or Steele-Richardson-Olszewski syndrome) and clinical predictors of survival in 24 patients with PSP confirmed by necropsy, who fulfilled the NINDS criteria for a neuropathological diagnosis of typical PSP. METHODS--Patients were selected from the research and clinical files of seven medical centres involving tertiary centres of Austria, England, France, and the United States. Clinical features were analysed in detail. The patients' mean age at onset of PSP was 63 (range 45-73) years. RESULTS--The most frequent clinical features (occurring in at least 75% of the patients) were early postural instability and falls, vertical supranuclear palsy, akinetic-rigid predominant parkinsonian disorder characterised by symmetric bradykinesia and axial rigidity unrelieved by levodopa, pseudobulbar palsy, and frontal release signs. Occasionally, segmental dystonia or myoclonus were described, but neither aphasia nor alien limb syndrome was reported. Fractures occurred in 25% of the patients but were unrelated to the severity of the gait or to the presence of falls. Median survival time was 5.6 (range 2-16.6) years. Onset of falls during the first year, early dysphagia, and incontinence predicted a shorter survival time. Age at onset, sex, early onset of dementia, vertical supranuclear palsy, or axial rigidity had no effect on prognosis of survival. Pneumonia was the most common immediate cause of death. PSP was most often clinically misdiagnosed as Parkinson's disease. Errors in diagnosis suggest that PSP is underdiagnosed. CONCLUSION--Progressive onset of early postural instability with falls or supranuclear vertical palsy in the fifth decade, should suggest the diagnosis of PSP. Onset of falls during the first year are emphasised, as they could lead to an early diagnosis and influence the prognosis of patients with PSP. Whether appropriate treatment of the dysphagia could prolong the survival of PSP patients needs to be explored.

Mealtime in nursing homes: the importance of individualized care

Malnutrition, a common problem among nursing home residents, contributes to: a) higher rates of infection, b) an impaired immune response, and c) the development of pressure sores. Eating habits are highly individualized and eating problems often occur due to a complex constellation of interacting factors such as poor oral health, medications, clinical conditions, and lack of attention to individual food likes and dislikes. By educating nursing assistants on how to provide individualized care at mealtime and ensuring that an adequate number of staff are available to assist those who need help, mealtime rather than being a task-oriented procedure will be an individualized, pleasant social event.

Surface EMG measurements at the throat during dry and wet swallowing

Within the sphere of dysphagia management, there is a growing need for the development of noninvasive methods of quantification of swallowing disorders. The purpose of the present investigation was to determine if surface electromyogram (EMG) at the throat could be measured during swallowing. Surface EMG was measured from 35 normal human subjects during dry and wet swallowing. The EMG signals recorded were highpass filtered using digital fourth order highpass Butterworth filter to eliminate baseline variations. Spectral analysis was performed on the filtered signals. The mean power values of the surface EMG signals were then calculated. Paired t-test between the mean power values of surface EMG during dry and wet swallowing showed a statistically significant difference (p < 0.005). The results of the study confirmed the hypothesis that surface EMG at the throat during swallowing could be measured. Mean power of surface EMG measurement provides a reliable noninvasive measure of swallowing.

Effect of occlusion of a tracheotomy tube on aspiration

The purpose of the present study was to investigate the effect of occlusion of a tracheotomy tube on aspiration utilizing fluoroscopy. Twenty consecutive tracheotomized patients referred for a modified barium swallow were included. Selection criteria were ability to tolerate tracheotomy tube occlusion during the modified barium swallow procedure, no surgery of the upper aerodigestive tract except tracheotomy, and no history of oropharyngeal cancer or stroke. There was 100% agreement among 3 independent reviewers on ratings of the presence or absence of aspiration. It was found that the occlusion status of the tracheotomy tube did not influence the prevalence of aspiration. Nine of 10 (90%) subjects who exhibited aspiration were over 65 years of age (mean = 72 years 2 months). No trends were observed for bolus consistency, type of tracheotomy tube, or presence/absence of a nasogastric tube and ratings of aspiration.

Prandial aspiration and pneumonia in an elderly population followed over 3 years

The purpose of our study was to prospectively determine pneumonia frequency and correlate it with prandial liquid aspiration and feeding status in frail elderly nursing home residents. Initially, 152 patients had video swallowing examinations (81 oropharyngeal dysphagia, 19 thoracic dysphagia, 52 without dysphagia). Those diagnosed with oropharyngeal impairment were subsequently managed with swallowing therapy or artificial feeding modalities. Patients were followed for 3 years (unless they expired earlier) and clinical courses were categorized according to the degree of prandial aspiration and feeding (PAF) status. Subjects with new lung infiltrates persisting for at least 5 days with appropriate clinical findings were diagnosed as having pneumonia and were classified according to the PAF status months in which these findings occurred. Fifty-six pneumonias were diagnosed during 4,280 months with the following frequencies: no aspiration months 0.6%; minor aspiration months 0.9%; major aspiration/oral feeding months 1.3%; major aspiration/artificial feeding months 4.4%, p < 0.001. Our results indicate that there is not a simple and obvious relation between prandial liquid aspiration and pneumonia. Artificial feeding does not seem to be a satisfactory solution for preventing pneumonia in elderly prandial aspirators.

The use of scintigraphy in the management of patients with pulmonary aspiration

Pulmonary aspiration was assessed using a scintigraphic swallowing procedure in 14 dysphagics in whom penetration of the larynx had been previously diagnosed. No patient had recent evidence of aspiration pneumonia. Imaging was performed during and following ingestion of a cupful of thin liquid admixed with between 1-2 mCi of Tc-99m sulfur colloid. Follow-up scans were obtained several hours later as needed to assess airway clearance. Five of the fourteen (36%) showed penetration distal to the trachea. Seven (50%) were indeterminate for aspiration, as isotope localized to the neck could not be clearly designated as being in either airway or foodway. Two subjects had negative studies. Of patients with subtracheal penetration, (1) fractions of the ingested material which were aspirated ranged from < 1%-25%, and (2) elimination from airways was complete or near-complete by 3 hours. The presence of an immediate or delayed cough was noted but did not correlate with subtracheal aspiration. Based on the results of scintigraphy, 8 of 9 patients on some form of liquid restriction at the time of testing were allowed to ease restrictions. Five patients without prior liquid restriction were allowed to continue to drink. We propose that scintigraphy provides important data on airway penetration and clearance that is useful in the dietary management of dysphagic patients.

Neurogenic dysphagia: what is the cause when the cause is not obvious?

The potential causes of neurogenic oropharyngeal dysphagia in cases in which the underlying neurologic disorder is not readily apparent are discussed. The most common basis for unexplained neurogenic dysphagia may be cerebrovascular disease in the form of either confluent periventricular infarcts or small, discrete brainstem stroke, which may be invisible by magnetic resonance imaging. The diagnosis of occult stroke causing pharyngeal dysphagia should not be overlooked, because this diagnosis carries important treatment implications. Motor neuron disease producing bulbar palsy, pseudobulbar palsy, or a combination of the two can present as gradually progressive dysphagia and dysarthria with little if any limb involvement. Myopathies, especially polymyositis, and myasthenia gravis are potentially treatable disorders that must be considered. A variety of medications may cause or exacerbate neurogenic dysphagia. Psychiatric disorders can masquerade as swallowing apraxia. The basis for unexplained neurogenic dysphagia can best be elucidated by methodical evaluation including careful history, neurologic examination, videofluoroscopy of swallowing, blood studies (CBC, chemistry panel, creatine kinase, B12, thyroid screening, and anti-acetylcholine receptor antibodies), electromyography, and magnetic resonance imaging (MRI) of the brain, plus additional procedures such as lumbar puncture and muscle biopsy as indicated. Little is known about aging and neurogenic dysphagia, specifically the relative contributions of natural age-related changes in the oropharynx and of diseases of the elderly, including periventricular MRI abnormalities, in producing dysphagia symptoms and videofluoroscopic abnormalities in this population.

Pilot study of 12-month outcomes of nursing home patients with aspiration on videofluoroscopy

The 12-month clinical outcomes of nursing home patients who underwent videofluoroscopic swallowing evaluation was determined. A retrospective review of 40 patients in a teaching nursing home who had videofluoroscopic swallowing studies from 1987 through 1989 was performed. Clinical outcomes measured included feeding tube placement, rehospitalization within 1 year, prolonged nursing home stay (> 6 months), pneumonia, and pneumonia death. It was determined if outcomes were associated with the presence of aspiration on videofluoroscopy and subsequent feeding tube placement. In the 12-month follow-up period, 17 of 40 patients (43%) who underwent videofluoroscopic swallowing evaluation developed pneumonia and 18 of 40 (45%) died. Twenty-two patients demonstrated aspiration on videofluoroscopy. Increased rehospitalization was the only outcome measure that was associated with the presence of aspiration on videofluoroscopy (p < or = 0.05). Of 22 patients with aspiration, 15 had feeding tubes placed. This group had a higher rate of pneumonia (p < or = 0.05) and pneumonia death (p < or = 0.05) compared with the 7 patients with aspiration who did not receive feeding tubes. Patients with nasogastric tubes had a higher death rate (7/9) than patients with gastrostomy tubes (2/8; p < or = 0.05), but similar rates of rehospitalization and pneumonia. Nursing home patients who underwent video-fluoroscopic swallowing evaluation had poor clinical outcomes at 12 months, regardless of their test results.(ABSTRACT TRUNCATED AT 250 WORDS)

Videofluoroscopic predictors of aspiration in patients with oropharyngeal dysphagia

The purpose of this investigation was to determine the relationship between aspiration and seven other variables indicative of pharyngeal stage dysphagia. Additionally, we looked at the relationship between aspiration and oral stage dysphagia. Multiple logistic regression analysis identified five independent predictors of aspiration that were significant at the p = 0.05 level: vallecular stasis, reduced hyoid elevation, deviant epiglottic function, diffuse hypopharyngeal stasis, and delayed initiation of the pharyngeal stage of the swallow. A linear trend was observed in that, as the severity of vallecular stasis, pyriform sinus stasis, diffuse hypopharyngeal stasis, or delayed initiation of the pharyngeal stage of the swallow increased, the proportion of patients who aspirated also increased. A stepwise logistic regression model furnished estimates of the odds ratio for each independent variable and can be used by clinicians to calculate the risk of aspiration in patients who demonstrate pharyngeal stage dysphagia.

The association of swallowing dysfunction and aspiration pneumonia

The medical literature has emphasized that aspiration of gastric contents or oral bacteria is a common cause of aspiration pneumonia. Swallowing disorders have been implicated in this disease but not studied at the time that aspiration pneumonia was diagnosed. A significant difference was found in the incidence of videofluoroscopically confirmed oropharyngeal swallowing problems in a group of patients diagnosed with aspiration pneumonia (AP) when compared with patients with nonaspiration pneumonia (NAP). Six of the 9 patients in the AP group aspirated during the videofluoroscopic evaluation and 2 others were considered to be at risk for aspiration. None of the 7 NAP patients demonstrated swallowing problems or aspiration. A significant difference in oral transit time also occurred between the two groups. Liquid was found to have a significantly faster oral transit time than paste or a cookie. Pharyngeal transit times were not found to be significantly different. Although there were only a small number of patients who met the criteria for this pilot study, a strong association was found between swallowing dysfunction and aspiration pneumonia.

Manofluorographic analysis of swallowing in the elderly

This study examined the effect of aging on the mechanisms of swallowing by comparing 16 elderly subjects (80 years +/- 5) with 20 healthy volunteers. Manofluorography was used to obtain quantitative and qualitative data of the pharyngeal swallow. Aging is associated with a significant decrease in the level of negative pressure resulting from the opening of the upper esophageal sphincter and with a substantial number of incomplete relaxations of the sphincter. In addition, several qualitative changes were noted.

Development of a multistage diet for dysphagia

A multistage dysphagia diet was developed by the nutrition and the speech-language pathology sections of an inpatient rehabilitation unit to meet a growing need for a diet that would allow dysphagic patients to eat safely and to progress to a wider variety of foods as their swallowing function improved. The diet was constructed empirically by evaluating all foods on the hospital menu for ease of swallowing. It consisted of five solid-food stages and two liquid stages; thickened liquids were provided for patients unable to manage regular liquids. Menus that offered patients choices among food items were designed for most stages. During planning and implementation of the diet, special attention was given to food production concerns, education of staff and other caregivers, and development of instructional materials for patients leaving the hospital. The diet met its goals of providing dysphagic patients with a maximum number of foods that could be swallowed safely, maintaining or improving nutritional status, avoiding unnecessary tube feeding, and winning the support of patients and caregivers.