|EVIDENCE BASED REVIEW
|Year : 2015 | Volume
| Issue : 1 | Page : 11-16
Therapeutic interventions by speech language pathologist in managing adult dysphagia: An evidence based review
Ruchika Mittal, Awadhesh Kumar Mishra, Ajith Nilakantan
Department of ENT, Army Hospital (Research and Referral), Delhi Cantt - 110 010, India
|Date of Web Publication||17-Dec-2015|
Department of ENT-HNS, Audiology and Speech Therapy, Army Hospital (Research and Referral), Delhi
Source of Support: None, Conflict of Interest: None
| Abstract|| |
The speech and language pathologist provides nonsurgical, nonpharmacological treatment to patients with oropharyngeal dysphagia. There is a notable lack of knowledge or awareness among the professionals in managing dysphagia using this therapeutic intervention. The present article, therefore, reviews the therapeutic interventions offered by speech and language pathologist in managing adult dysphagia and its efficacy data. Literature was searched and all the therapeutic interventions offered were included and studies were quoted mentioning their efficacy. In general, positive therapy effects were found.
Keywords: Adult, dysphagia, speech language pathology, therapeutic intervention
|How to cite this article:|
Mittal R, Mishra AK, Nilakantan A. Therapeutic interventions by speech language pathologist in managing adult dysphagia: An evidence based review. J Laryngol Voice 2015;5:11-6
|How to cite this URL:|
Mittal R, Mishra AK, Nilakantan A. Therapeutic interventions by speech language pathologist in managing adult dysphagia: An evidence based review. J Laryngol Voice [serial online] 2015 [cited 2020 Jan 19];5:11-6. Available from: http://www.laryngologyandvoice.org/text.asp?2015/5/1/11/172105
| Introduction|| |
Dysphagia or difficulty in swallowing, usually presents with a neurological or structural disorder that interferes with the smooth and efficient movement of food from the mouth to the stomach. It is represented with symptoms of aspiration, slowed or labored eating, and weight loss.  It needs to be distinguished from other symptoms of odynophagia which are defined as painful swallowing and globus which is the sensation of a lump in the throat. Speech pathologist is involved in managing oropharyngeal dysphagia in adults. Once the problem is at, or below, the level of the lower pharynx (i.e. where swallowing becomes involuntary), then little can be gained from behavioral intervention. Esophageal level dysphagia is usually managed surgically/medically. 
Dysphagia can occur in all age groups resulting from congenital abnormalities, structural damage, and/or medical conditions. Adult dysphagia is usually seen in patients with neurological etiologies such as motor neuron disease, Parkinson's disease, or stroke or in patients with head and neck cancer or due to more subtle process of aging. Swallowing problems are a common complaint among older individuals, and the incidence of dysphagia is higher in the elderly.  The present review article focuses on therapeutic interventions offered by speech and language pathologist in managing adult dysphagia.
The therapeutic treatment offered by speech pathologist in dysphagia management can be divided into compensatory and rehabilitative therapy strategies. Compensatory strategies refer to those therapy techniques that are designed to improve the swallowing physiology, whereas rehabilitative therapies are aimed at changing the swallowing physiology. 
| Compensatory strategies|| |
Compensatory strategies are those treatment techniques that improve or redirect the flow of food and eliminate the patient's symptoms of aspiration. These include postural changes, changes of volume/speed of food delivery, changing oral-sensory awareness, and/or using prostheses and dietary changes. 
They have been found effective in eliminating and reducing aspiration in 75-80% of patients. Patients may benefit from these techniques either tried in one posture or in a combination of postures. , The postural techniques have good evidence-based research to support their efficacy. However, due to physical constraints or cognitive deficits, some people do not benefit.  The evaluation of postural techniques takes place under video fluoroscopic swallowing study, which allows an objective assessment of the changes in swallow status and reduction/elimination of aspiration when the therapeutic technique is used.
Chin tuck/chin to chest
It holds the bolus more anteriorly prior to swallowing and narrows the airway entrance. This technique is used with patients who have delayed triggering of the swallow reflex, premature spillage into pharynx, and decreased tongue base movements. , Shanahan et al.  and Lewin et al.  studied the effects of chin tuck during a single session in a group of patients suffering from aspiration as a result of, respectively, diverse neurological pathologies (n = 30) and esophagectomy (n = 21). Both studies indicated elimination of aspiration: 50%  and 81%  in all subjects.
It facilitates the bolus posteriorly. It is used with oral cancer patients who have adequate cognition and pharyngeal swallow but unable to move the bolus posteriorly. 
Head rotation toward the damaged side
This technique uses stronger musculature to improve pharyngeal peristalsis. It is used with patients with unilateral pharyngeal paresis, unilateral vocal fold palsy or hemilaryngectomy.  Logemann et al.  studied the effects of head rotation in acute brainstem stroke patients with unilateral oropharyngeal dysphagia (n = 5). The fraction of the bolus swallowed, and the upper esophageal sphincter diameter increased significantly with the head turned toward the paretic side.
Tilting head or upper body to the stronger side
With this technique, bolus is directed to the stronger side by gravitational forces. This is used in cases with unilateral oral and pharyngeal palsy on the same side of the mouth and pharynx. ,,
Techniques to improve speed of triggering the pharyngeal swallow
Tactile stimulation ,, and electrical stimulation  enhances sensory input and thereby trigger a more efficient and speedier triggering of the pharyngeal swallow. This technique provides an altering stimulus to the cortex and brainstem and facilitates faster triggering of the pharyngeal stage of the swallow and reduces the delay for up to several swallows later, before the reapplication of the icing is necessary. An exaggerated suck swallow with the lips closed and pumping with the tongue and jaw to draw saliva into the mouth facilities triggering of the swallow and also allows saliva to be taken to the back of the mouth, which may help some oral cancer patients who have limited saliva control. There are no studies to demonstrate the efficacy of such a technique. This technique is used by Logemann  with Parkinson's disease and oral cancer patients who have difficulty in saliva management. Bülow et al.  compared the outcome of neuromuscular electrical stimulation (n = 13) with that of traditional swallowing therapy (n = 12) in stroke patients using video fluoroscopy, dietary level, oral motor function testing, and a patient's self-evaluation. Although statistically significant positive therapy effects were found for both groups combined, no statistically significant difference in therapy effect between the groups was present. Two other randomized controlled trials conducted by Rosenbek et al. , were related to the thermal application at the anterior faucial pillars. The total subject population included seven multiple-stroke patients. Subjects were randomly assigned to a week long period of thermal application (n = 6) or to a week of no therapy (n = 1). The thermal application consisted of on average 18 trials per session 5 times per day. Each trial consisted of repeated strokes on the pillars using a chilled laryngeal mirror followed by a swallow (water or ice chips). Overall, no strong evidence was found that dysphagia improved after 2 weeks of thermal application alternating with 2 weeks of no thermal application. The second study  used a cross-over design to determine the short-term effects of thermal application. A group of stroke subjects (n = 22) swallowed 10 times in untreated and treated conditions. It was found that swallowing durations were highly variable within and across subjects. Furthermore, thermal stimulation significantly reduced the duration of stage transition and total swallow duration compared to no treatment. Shaw et al.  performed a retrospective study on surface electrical stimulation in 18 patients suffering from diverse neurological pathologies or postlaryngeal radiotherapy. Patients were divided into four groups according to their pretherapy status : n0 ear-functional swallow (n = 2), limited swallowing requiring compensatory manoeuver (n = 4), enteral feedings with ability to swallow certain consistencies (n = 7), or tube feeding (n = 5). Based on varying evaluation techniques per patient, the overall conclusion was that transcutaneous neuromuscular electrical stimulation may help patients with mild to moderate dysphagia. However, patients with the most severe dysphagia did not gain independence from tube feeding.
Changes in volume/speed of food presentation/texture/taste
Many swallowing problems can be solved simply by regulating the amount of the food taken by bolus, the speed at which the food is given and by changing the texture and taste. In general, the hierarchy of foods from easiest to most difficult to swallow is semisolids, solids and then liquids. However, this is not true of all dysphagic patients. Patients with reduced tongue base posterior movement, for example, are said to swallow liquids easiest, with thick, higher viscosity foods being the most difficult. Moreover, food which is more highly flavored than typical hospital and institutional bland are more easily swallowed. Logemann  has provided a table listing the easiest and most difficult food consistencies for patients with different swallowing disorders. Bhattacharyya et al.  compared the effects of liquid versus paste boluses in a group of subjects with unilateral vocal fold paralysis. Among all subjects showing aspiration and/or penetration (31 of 55 subjects), 25% aspirated on thin liquids but not on paste boluses. Penetration occurred in 79% of the subjects when using liquid and 50% when using paste. The authors concluded that thicker food consistencies were likely to be safer for oral intake in patients with unilateral vocal fold paralysis due to decreased risk of laryngeal penetration and aspiration.
Techniques to improve oral sensory awareness
Presenting cold/sour/larger bolus, increased downward pressure of the spoon against the tongue when food is presented, presenting a bolus needing chewing, allowing self-feeding from hand to mouth are some of the techniques usually used with people who present with a delayed onset of the swallow either at the oral or at the pharyngeal stage.  Logemann et al.  studied the effects of changed bolus acidity and volume in stroke patients (n = 19) and a group of patients with other mixed neurological etiologies (n = 8). Sour boluses compared to nonsour boluses significantly improved the timing of the onset of the oral swallow. Stroke patients exhibited reduced pharyngeal delay time, oral transit time, and improved swallow efficiency, whereas the other group exhibited reduced aspiration. Increasing the bolus volume significantly increased oral residue and number of swallows, but decreased the oral transit time, pharyngeal delay time, and pharyngeal transit time in both groups.
Intraoral prostheses provide invaluable compensatory aids in improving swallowing in patients who have undergone surgical resections including patients with head and neck cancer. Some of the commonly used prosthesis with dysphasic patients are palatal obturator and palatal lift. The majority of patients who are using intraoral prostheses due to oral or oropharyngeal deficits usually experience either mixed results or have unchanged oral functions. ,
| Rehabilitative therapy|| |
Rehabilitative therapy is designed to change the swallowing physiology and is divided into direct and indirect intervention. In direct therapy, the patient is being taught to gain control over his bolus using small amounts of food or liquid, using specified swallowing sequences. This is used when patients can swallow small amounts with no aspiration. Indirect therapy is for patients for whom oral intake is considered unsafe, and it involves no food or liquid being used. With such patients, oro-motor exercises, chewing and swallowing maneuvers are used, and the patient only swallows his own saliva. 
The oro-motor strengthening programs include a range of motion exercises and resistance exercises to improve the muscular function of the lips, jaw, and tongue. Although these programs are widely used, efficacy data are lacking.  All such exercises involve moving the targeted structure as far as possible in the desired plane, holding that position, and then relaxing.  Frequency or repetition for such exercises has been recommended to be 6-10 times per day in sets of five repetitions.  These exercises are particularly important for the patient with oral cancer who receives irradiation postoperatively to prevent muscular fibrosis and maintain the greatest amount of structural mobility. Some patients may need to continue such an exercise program permanently because of the formation of fibrous connective tissue.
| Swallowing maneuvers|| |
Five swallowing maneuvers, all designed to change swallowing physiology have been researched and developed up to date. When teaching swallowing maneuvers, it is best to keep the instructions as simple and straightforward as possible.
This technique is useful in those patients who demonstrate premature spillage of material into the airway and incomplete airway protection secondary to neuromuscular or iatrogenic disorders. It is designed to teach voluntary closure of the vocal folds before, during and after the swallow. Instructions to the patient involve inhale and hold your breath and swallow firmly while holding your breath. Cough immediately, after the swallow and before breathing in. The lacuna in the technique is that this is a difficult task as almost everyone inhales immediately after the swallow, before a cough, thereby drawing any aspirate which may be left on the top of the vocal folds into the subglottis. , Logemann used supraglottic swallow in a small group of nine patients who had supraglottic laryngectomy, three of the nine patients were able to take in food orally at 2 weeks postoperatively, whereas seven of the nine patients were successful oral feeders by 3 months. 
The super-supraglottic swallow follows the same basic procedure as supraglottic swallow but adds an element of increased effort to increase anterior tilting of the arytenoids and retraction of the tongue base for increased airway protection and pressure on the bolus. Instructions to the patient would involve an approximation of the following breath in, hold your breath, and bear down hard. After the swallow, cough to clear any leftover food. The effort of bearing down usually closes the false cords, tilting the arytenoids posteriorly to meet the base of the epiglottis, thereby closing the airway entrance as tightly as possible. This technique may need to be practiced with dry/saliva swallows before introducing bolus, particularly in those patients with respiratory compromise. , Logemann et al.,  Studied the effects of a super-supraglottic swallow in a group of head and neck cancer patients (n = 9). The maneuver resulted in fewer swallowing motility disorders and in some cases the elimination or reduction of aspiration.
In this technique, the patient is instructed to exert more pressure on the bolus, as if it were a larger amount of material, or may be asked to bear down, or squeeze harder to increase bolus clearance through the pharynx. This technique is useful when postradiotherapy and/or surgical treatment results in pharyngeal fibrosis and the patient has reduced pharyngeal sensation. It is often helpful to allow the patient to see the results of this technique radiographically so that he or she may visualize the results of increased effort. ,
The Mendelsohn maneuver is designed to increase the duration of laryngeal elevation during swallowing, thereby increasing the duration and extent of the cricopharyngeal opening. ,, Instructions to the patient involves approximation, swallowing their saliva a few times and feeling their neck movements as they swallow. Feel the Adam's apple or voice box, lift as you swallow. When you swallow and feel the lift of the voice box and do not let it drop back down. Hold it up with your muscles for several seconds.
In this maneuver, the patient is instructed to lie down on the floor or bed and instructed to try to lift head to see toes, without raising their shoulders. Hold that posture for a minute and then relax for a minute. This exercise is repeated 3 times, and then 30 repetitive short head raisings are done, and the whole exercise is carried out 3 times a day. It is useful to strengthen laryngeal movements during swallowing and has been used in older normal individuals to strengthen hyoid and laryngeal movements. ,
| Studies on combination of interventions|| |
Hwang et al.  evaluated the effects of preemptive swallowing stimulation on the recovery of swallowing function in patients who had been intubated for at least 48 h in the Intensive Care Unit (n = 33). Patients were randomly assigned to either an experimental group receiving stimulation (n = 15) or a control group receiving no stimulation (n = 18). The preemptive stimulation therapy consisted of thermal-tactile stimulation, oral stimulation, oral massage, digital manipulation, and a cervical range-of-motion exercise. A single therapist performed therapy for 15 min twice a day for 6 days per week. Using videofluoroscopy, it was concluded that stimulation during intubation assisted in the recovery of swallowing function. Oral transit time, oral pharyngeal transit time, and oropharyngeal swallowing efficiency were significantly faster in the experimental group than in the control group. Differences between both groups with respect to the percentage of aspiration and swallowed volume were not statistically significant.
Carnaby et al.  compared the change in dietary status in a large group of acute stroke patients (n = 303) after usual care (n = 102), standard low-intensity intervention (n = 101), and standard high-intensity intervention (n = 100). Usual care consisted of patient management by the attending physicians as per usual practice. Treatment, if offered, consisted mainly of supervising feeding and taking precautions for safe swallowing (e.g., positioning, slower pace of eating). The standard low-intensity intervention was based on compensation strategies, mainly environmental modifications (e.g., positioning), safe swallowing advice, and dietary modification. These interventions were carried out under the direction of a speech pathologist 3 times per week for up to 1 month. High-intensity intervention referred to direct swallowing exercises (e.g., effortful swallowing and supraglottic swallow technique) and appropriate dietary modification. These exercises were done every working day for a month or daily during the hospital stay (if < 1 month). After 6 months, the percentage of patients returning to a normal diet and receiving usual care, standard low-intensity, or high-intensity intervention was 56%, 64%, and 70%, respectively. A functional swallow without swallowing complications was achieved by 32% of the patients who received usual care, 43% who received the standard low-intensity intervention, and 48% who received the high-intensity intervention. In patients who received standard therapy, medical complications, chest infections, and death or institutionalization decreased significantly.
Lin et al.  Studied the outcome of a swallowing training protocol in a group of stroke patients (n = 49).The protocol included direct therapy (compensatory strategies such as diet modification, environment arrangement, positioning, and swallowing maneuvers) and indirect therapy (thermal stimulation, physical maneuvers like lip, and lingual exercises). Patients were divided into an experimental group (n = 35) that received the swallowing training protocol over a period of 8 weeks (30 min per day, 6 days per week) and a control group (n = 14) that received no therapy. After the training, mean differences for the experimental group with respect to volume per second, volume per swallow, mid-arm circumference, and body weight between pre- and post-training were significantly higher than for the control group. However, the mean differences in neurological examination and choking frequency during meals for the experimental group were significantly lower than for the control group. In a study by Elmståhl et al.,  the effects of therapy on nutritional and anthropometric variables in a group of acute stroke patients (n = 38) were described. During a period of about 2 months, therapy focused on oral motor exercises, swallowing strategies (supraglottic swallowing, effortful swallowing, Mendelsohn maneuver, and thermal stimulation), head and neck positioning, and diet modifications. About 60% of all patients responded with better swallowing function and improved nutritional status at follow-up, thereby reducing the risk of developing malnutrition. Treatment reduced the degree of oral dysfunction (dissociation) and pharyngeal dysfunction (penetration and constrictor paresis). Changes in subjective complaints, however, did not correlate with swallowing function or nutritional improvements.
The diversity in the type of therapy is impressive. Some interventions described are well known, but certain studies describe rather unconventional therapy concepts. Besides this variety of interventions, literature reveals enormous variation in the duration of therapy. Some studies claim significant (short-term) improvement after a single treatment session, whereas others report a long series of sessions. All the above studies provide information only on the short-term effects of the therapy but are silent on the long-term effects.
It is of vital importance that all persons involved with the dysphagia patients both professionals and family members have a clear understanding of the rationale behind selected treatment techniques. Education in the process of swallowing and the impact of the disorders is an integral part of any rehabilitation program. Use of a videotaped modified barium swallow/videofluoroscopic studies can provide visual evidence of the swallowing disorder and the positive impact of facilitative and compensatory strategies chosen. Active participation of all involved is the key to success in returning to more normalized feedings with the greatest safety. The efficacy study by DePippo et al. is an illustration of the value of family training in dysphagia management. In this study, patients receiving only one session of instructions in diet modifications and swallowing techniques did as well on follow-up measures as those who received daily therapy for a rehearsal of compensatory techniques and dietary management. 
This review is an attempt to provide to the reader and therapist information about the treatment of dysphagia so as to be able to more aptly treat their patients. It will also persuade the therapist in this field to plan further studies in this field of dysphagia.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
Logemann J. Evaluation and Treatment of Swallowing Disorders. Austin, TX, USA: PRO-ED; 1998.
Perry A. Dysphagia: Management and intervention. In: Glesson M, editor. Scott Brown′s Otorhinolaryngology, Head and Neck Surgery. 7 th
ed. CRC Press; 2084-93.
Shamburek RD, Farrar JT. Disorders of the digestive system in the elderly. N Engl J Med 1990;322:438-43.
Logemann JA. Behavioral management for oropharyngeal dysphagia. Folia Phoniatr Logop 1999;51:199-212.
Rasley A, Logemann JA, Kahrilis PJ, Rademaker AW, Pauloski BR, Dodds WJ. Prevention of aspiration during videofluroscopic swallowing studies: Value of change in posture. Am J Radiol 1993;160:1005-9.
Welch MV, Logemann JA, Rademaker AW, Kahrilas PJ. Changes in pharyngeal dimensions effected by chin tuck. Arch Phys Med Rehabil 1993;74:178-81.
Shanahan TK, Logemann JA, Rademaker AW, Pauloski BR, Kahrilas PJ. Chin-down posture effect on aspiration in dysphagic patients. Arch Phys Med Rehabil 1993;74:736-9.
Lewin JS, Hebert TM, Putnam JB Jr, DuBrow RA. Experience with the chin tuck maneuver in postesophagectomy aspirators. Dysphagia 2001;16:216-9.
Poertner LC, Coleman RF. Swallowing therapy in adults. Otolaryngol Clin North Am 1998;31:561-79.
Logemann JA, Kahrilas PJ, Kobara M, Vakil NB. The benefit of head rotation on pharyngoesophageal dysphagia. Arch Phys Med Rehabil 1989;70:767-71.
Lazzara G, Lazarus C, Logeman JA. The impact of thermal stimulation on the trigerring of swallow reflex. Dysphagia 1986;1:73-7.
Rosenbeck JC, Roecker EB, Wood ML, Robbins JA. Thermal application reduces the duration of stage transition in dysphagia after stroke. Dysphagia 1996;11:198-206.
Blumenfeld L, Hahn Y, Lepage A, Leonard R, Belafsky PC. Transcutaneous electrical stimulation versus traditional dysphagia therapy : a0 nonconcurrent cohort study. Otolaryngol Head Neck Surg 2006;135:754-7.
Logemann JA. Managemet of dysphagia poststroke. In: Chapey R, editor. Language Intervention Strategies in Adult Aphasia. 3 rd
ed. Baltimore: William and Wilkins; 1994. p. 503-12.
Bülow M, Speyer R, Baijens L, Woisard V, Ekberg O. Neuromuscular electrical stimulation (NMES) in stroke patients with oral and pharyngeal dysfunction. Dysphagia 2008;23:302-9.
Rosenbek JC, Robbins J, Fishback B, Levine RL. Effects of thermal application on dysphagia after stroke. J Speech Hear Res 1991;34:1257-68.
Rosenbek JC, Roecker EB, Wood JL, Robbins J. Thermal application reduces the duration of stage transition in dysphagia after stroke. Dysphagia 1996;11:225-33.
Shaw GY, Sechtem PR, Searl J, Keller K, Rawi TA, Dowdy E. Transcutaneous neuromuscular electrical stimulation (VitalStim) curative therapy for severe dysphagia : m0 yth or reality? Ann Otol Rhinol Laryngol 2007;116:36-44.
Logemann JA. The dysphagia diagnostic procedure as a treatment efficacy trial. Clin Commun Disord 1993;3:1-10.
Bhattacharyya N, Kotz T, Shapiro J. The effect of bolus consistency on dysphagia in unilateral vocal cord paralysis. Otolaryngol Head Neck Surg 2003;129:632-6.
Logemann JA, Pauloski BR, Colangelo L, Lazarus C, Fujiu M, Kahrilas PJ. Effects of a sour bolus on oropharyngeal swallowing measures in patients with neurogenic dysphagia. J Speech Hear Res 1995;38:556-63.
Logemann JA, Kahrilas PJ, Hurst P, Davis J, Krugler C. Effects of intraoral prosthetics on swallowing in patients with oral cancer. Dysphagia 1989;4:118-20.
Pauloski BR, Rademaker AW, Logemann JA, Colangelo LA. Speech and swallowing in irradiated and nonirradiated postsurgical oral cancer patients. Otolaryngol Head Neck Surg 1998;118:616-24.
Langmore SE, Miller RM. Behavioral treatment for adults with oropharyngeal dysphagia. Arch Phys Med Rehabil 1994;75:1154-60.
Groher ME. Dysphagia. Management : g0 eneral principles and guidelines. Dysphagia 1991;6:67-70.
Logemann JA, Rademaker AW, Pauloski BR, Kahrilas PJ. Effects of postural change on aspiration in head and neck surgical patients. Otolaryngol Head Neck Surg 1994;110:222-7.
Logemann JA, Pauloski BR, Rademaker AW, Colangelo LA. Super-supraglottic swallow in irradiated head and neck cancer patients. Head Neck 1997;19:535-40.
Ohmae Y, Logemann JA, Kaiser P, Hanson DG, Kahrilas PJ. Effects of two breath-holding maneuvers on oropharyngeal swallow. Ann Otol Rhinol Laryngol 1996;105:123-31.
Pouderoux P, Kahrilas PJ. Deglutitive tongue force modulation by volition, volume, and viscosity in humans. Gastroenterology 1995;108:1418-26.
Kahrilas PJ, Logemann JA, Krugler C, Flanagan E. Volitional augmentation of upper esophageal sphincter opening during swallowing. Am J Physiol 1991;260 (3 Pt 1):G450-6.
Lazarus C, Logemann JA, Gibbons P. Effects of maneuvers on swallowing function in a dysphagic oral cancer patient. Head Neck 1993;15:419-24.
Shaker R, Kern M, Bardan E, Taylor A, Stewart ET, Hoffmann RG, et al.
Augmentation of deglutitive upper esophageal sphincter opening in the elderly by exercise. Am J Physiol 1997;272 (6 Pt 1):G1518-22.
Hwang CH, Choi KH, Ko YS, Leem CM. Pre-emptive swallowing stimulation in long-term intubated patients. Clin Rehabil 2007;21:41-6.
Carnaby G, Hankey GJ, Pizzi J. Behavioural intervention for dysphagia in acute stroke : a0 randomised controlled trial. Lancet Neurol 2006;5:31-7.
Lin LC, Wang SC, Chen SH, Wang TG, Chen MY, Wu SC. Efficacy of swallowing training for residents following stroke. J Adv Nurs 2003;44:469-78.
Elmståhl S, Bülow M, Ekberg O, Petersson M, Tegner H. Treatment of dysphagia improves nutritional conditions in stroke patients. Dysphagia 1999;14:61-6.
DePippo KL, Holas MA, Reding MJ, Mandel FS, Lesser ML. Dysphagia therapy following stroke : a0 controlled trial. Neurology 1994;44:1655-60.