Eating and Breathing: Interactions Between Respiration and Feeding on Solid Food

Chewed solid food accumulates in the oropharynx prior to swallowing. The mechanism for preventing aspiration during this interval is unknown, but may be related to respiration. The purpose of this study was to determine how eating, especially bolus formation in the pharynx, affects respiration. We examined nasal air pressures, masseter electromyography (EMG), and videofluorography (VFG) of four normal young adults eating 8 g each of banana and cookie (two trials each food). Resting respiration was recorded for 30 s before eating. Respiratory cycles (RCs) were classified as prefeeding, feeding (excluding cycles with included swallows), and swallowing cycles. RC duration was greater for swallowing than for feeding and prefeeding RCs (P < 0.001). There were up to three swallows in a single RC, but the increase in swallowing RC duration was greater than swallow duration. Swallow apnea began before bolus transport through the hypopharynx and ended as the bolus tail entered the esophagus. There were semirhythmic perturbations in nasal air pressure associated with masseter activity during chewing, suggesting that there was oronasal airflow during jaw closing via the velopharyngeal isthmus. The most important finding was that bolus aggregation in the valleculae usually occurred during an extended plateau in nasal air pressure following active expiration. This suggests that aspiration during eating is prevented by inhibiting respiration during bolus formation in the oropharynx. Supported in part by award #R01-DC02123 from the National Institute on Deafness and other Communication Disorders of the National Institutes of Health.     

McGill Ingestive Skills Assessment (MISA): Development and First Field Test of an Evaluation of Functional Ingestive Skills of Elderly Persons

There is a lack of reliable and valid clinical assessment tools for individuals with loss of ingestive skills. The McGill Ingestive Skills Assessment (MISA) was developed to facilitate the reliable and valid bedside assessment of elderly persons with feeding difficulties. Items were generated by a literature review and selected with the collaboration of a multidisciplinary team. The first version of the MISA comprised 190 items in 7 scales, covering the domains of medical history, mealtime environment, physical characteristics of the patient, food textures consumed, solid ingestion, liquid ingestion, and behaviors related to self-feeding. The first field test for item selection included 50 individuals, aged 60 years and older, living in the community, supervised housing, and long-term care centers. After field testing, 134 items were eliminated due to poor face validity, redundancy, or poor psychometric performance. The remaining 56 items were provided with 4 response categories and were reorganized into 5 scales. The revised version was field tested to determine its preliminary psychometric properties on 33 individuals, 60 years of age and older, residing in a long-term care center. Six items were eliminated due to redundancy after the second field test. Analyses of the revised version resulted in the elimination of another 6 items that were redundant or that demonstrated poor reliability. Internal consistency of all scales is 0.86 and interrater agreement is 0.92. These analyses suggest that the psychometric properties of the MISA are adequate for diagnosis and treatment planning. This supports its readiness for clinical use following further reliability and validity testing with a larger sample Presented in part to the Dysphagia Research Society, Toronto, Ontario, Canada, October 1997, and Burlington, VT, October 1999, and to the American Geriatrics Society, Nashville TN, May 2000.     

神经生长因子在老年吞咽功能障碍治疗中的应用

目的观察神经生长因子对改善老年吞咽功能障碍,减少误吸发生的的临床疗效,为其临床应用提供参考。方法将66例存在吞咽功能障碍的老年患者采用随机数字表法分成两组。治疗组32例,在对其基础疾病常规治疗的同时,使用鼠神经生长因子和Intelect Vital Stim吞咽障碍治疗工作站联合治疗;对照组34例,除常规健康宣教和治疗外,单用Intelect Vital Stim吞咽障碍治疗工作站治疗。根据治疗前后标准吞咽功能评估量表(SSA)、洼田饮水试验评分结果判断临床疗效。结果 6周治疗后,两组的SSA评分均较治疗前显著下降,误吸率降低,差异有统计学意义(P0.05),但治疗组误吸率下降幅度大于对照组;两组间疗效比较,治疗组的总有效率为62.50%,优于对照组35.29%,差异有统计学意义(P0.05)。结论神经生长因子联合Vital Stim电刺激疗法治疗老年人吞咽功能障碍可减少误吸发生率。     

Prevalence of swallowing complaints and clinical findings among 50–79-year-old men and women in an urban population

To determine the prevalence of swallowing and esophageal complaints in the general population, 300 men and 300 women were asked to answer a mailed questionnaire. The participation rate was 92.5%. Complaints were reported by 35%. The most common complaints were symptoms associated with gastroesophageal reflux (GER) and globus sensation, both with a rate of occurrence of 20%. Obstruction of the bolus reported by 3% was the individual symptom that most frequently brought patients to the doctor. To validate the questionnaire and to study possible organic causes behind these symptoms, 46 persons with symptoms were invited to undergo further examination. Cineradiography of the pharynx revealed that 7 of 14 patients with symptoms of GER had abnormalities in the esophagus. Eleven of 55 patients with GER symptoms at least once a week underwent endoscopy. One case of erosive esophagitis and one case of gastric ulcer were diagnosed. Four of nine patients with obstructive symptoms had defective closure of the laryngeal vestibule shown by cineradiography. Endoscopy in four patients with obstructive symptoms revealed benign findings. Thus, an epidemiologic study of patients with swallowing symptoms documented a low incidence of serious organic disease.     

Serving Temperature Viscosity Measurements of Nectar- and Honey-Thick Liquids

This study reports the viscosity (thickness) of nectar- and honey-thick liquids measured at a typical serving temperature. Centipoise (cP) measurements were compared for three products (two starch and one gum-based thickener) mixed with five beverages that set for three time intervals (manufacturer-recommended time to thicken, 10 min, and 30 min). The serving temperature of the cold beverages was 4°C (water, apple juice, orange juice, and milk), and the hot beverage (coffee) was measured at 70°C. Statistical analysis showed that all factors interacted with one another, meaning that the viscosity of a nectar- or honey-like liquid varies greatly depending on the type of thickening agent and beverage combination in relation to the amount of time it thickens. Simply Thick, the gum-based thickener, typically produced samples that were the least viscous but they maintained a more consistent level of thickness over time. Serving temperature results are contrasted with viscosity measurements collected at room temperature, showing variable thickening patterns especially related to the type of thickening agent.     

Beyond Efficacy and Effectiveness: Conducting Economic Analyses During Clinical Trials

Few studies have examined cost issues in the field of dysphagia. This study presents cost data collected during a clinical trial in speech–language pathology, demonstrating the types of cost analyses that can be conducted and highlighting obstacles and issues facing investigators who seek to conduct economic analyses in this arena. Seventy-nine patients were enrolled in the clinical trial to assess the impact of a swallowing intervention on swallowing and speech function. The patients were at least one year past treatment for head and neck cancer. No significant intervention differences were detected in these outcomes. A companion economic analysis was conducted in 37 of these patients using patient diaries and followup with identified health care providers. Analyses indicated that (1) the intervention did not significantly reduce health care expenditures; (2) indirect costs and costs of hospitalizations are both important factors to consider during a trial; and (3) health care costs of this population are high relative to the rest of the U.S. population. Attrition from the overall study population can pose a serious threat to the viability of an economic study. The article concludes with a discussion of how these issues can be addressed in future studies.This research was supported by NIH/NCI P01 CA40007 and NIDCD U01 DC03206.     

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 thep=0.05 level: vallecular stasis, reduced hyoid elevation, deviant epiglottic function, diffuse hypopharygeal stasis, and delayed initiation of the pharyngeal stage of the swallow. A linear trend was observed in that, as the severity of vallecular 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.This work was conducted while all authors were at the VA Medical Center, Iowa City, Iowa, USA.     

吞咽训练对脑卒中后吞咽障碍患者的效果研究

将60例脑卒中后合并吞咽障碍患者按住院顺序单双号分成试验组和对照组各30例,在神经内科常规药物治疗基础上,试验组每日加以吞咽康复训练。4周后试验组吞咽功能改善情况优于对照组[93％（28／30）比63％（19／30）,P〈0．05],且吸人性肺炎发生率少于对照组[3．3％（1／30）比26．7％（8／30）,P〈0．05]。     

Radiation Dose in Videofluoroscopic Swallow Studies

Videofluoroscopy has become an increasingly important armament in the investigation and assessment of swallowing disorders. However, very little work has been published on the radiation dose used in such examinations and currently there is no national diagnostic reference level in the United Kingdom. Videofluoroscopy in our hospital is performed predominantly by one radiologist (IZM) in a single fluoroscopy room. We recorded the screening times of 230 patients over a 45-month period. Screening time ranged from 18 to 564 s (median = 171 s) associated with a median dose-area product of 1.4 Gy cm². This is below the third quartile level of 2.7 Gy cm² for all such examinations performed across the northern England. The effective dose associated with a typical videofluoroscopy dose-area product is 0.2 mSv. Videofluoroscopy is the most appropriate instrumental examination for assessing oropharyngeal swallow biomechanics and intervention strategies. This data set is based on the largest number of videofluoroscopy swallow studies published to date. Our results show that videofluoroscopy can be performed using minimal radiation doses. This study was performed at Freeman Hospital, Newcastle upon Tyne, UK.     

Strength-Training Exercise in Dysphagia Rehabilitation: Principles,Procedures, and Directions for Future Research

Dysphagia rehabilitation, historically, has focused a great deal on various compensations during swallowing to prevent aspiration and/or improve safety and efficiency. Exercise, in general, has been a part of the dysphagia rehabilitation landscape. However, heightened discussions in the field regarding best practices for exercise training, particularly strengthening, raise more questions than answers. The intent of this paper is to (1) explore the overriding principles of neuromuscular plasticity with regard to strength training, (2) evaluate how current exercise-training interventions in dysphagia rehabilitation correspond to these principles, and (3) postulate directions for future study of normal and disordered swallowing and determine how to incorporate these principles into dysphagia rehabilitation.