Maxfacts

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Swallow

The many causes of dysphagia affecting the oral and oropharyngeal space include degenerative conditions (such as motor neuron disease, myasthenia gravis, multiple sclerosis, Parkinson’s disease), neurological conditions (such as cerebral palsy, dementia, stroke, fetal alcohol syndrome) and genetic disorders (such as Down syndrome, Rett syndrome). The assessment and management of dysphagia related to these conditions is not discussed here.

Our discussion of swallowing assessments and nonsurgical management concentrates on dysphagia related to maxillofacial conditions, in particular

Dysphagia management for most of these conditions needs to be seen in conjunction with surgical interventions and other treatment modalities, such as radiotherapy, addressing these underlying condition(s). It is important to remember that not only are there many different forms of dysphagia, but generally dysphagia affects different people, even with very similar conditions, in different ways. Relevant impairments of the swallowing process include reduced lip seal, reduced tongue motility, delayed swallowing reflex, reduced elevation of the soft palate, reduced larynx elevation, reduced movement of the epiglottis and/or hyoid, severe xerostomia, trismus, reduced jaw movements – and combinations of swallowing impairments. Hence, our pages can only give a general overview with some examples included, and highlighting the need for individual assessment and support.

Some general remarks

The procedures related to assessment and non-surgical management of swallowing problems vary, depending on the underlying problem. Obviously, the situation for an infant with cleft lip & palate is different from the situation of an adult following major maxillofacial surgery and/or radiotherapy applied to the head & neck region.

Nevertheless, the overarching theme to swallowing assessment is to establish the ability, efficiency, and above all the safety of swallowing. The time it takes for somebody to complete a single swallow is a crude measure of the efficiency of swallowing. The ability to swallow is correlated with the degrees of independence from tube feeding in order to provide somebody with all their daily nutritional needs by mouth. The safety of swallowing is related to the presence/absence of aspiration and pooling of residual food and/or saliva.

These various criteria taken together inform recommendations for the respective optimum management of dysphagia. These strategies can (and do) vary widely and may change considerably over time, with some dysphagia conditions likely to improve over time, and others having a tendency to get worse. Recent studies highlight unmet needs of many head & neck cancer patients for better pre-treatment information about expected swallowing and speech outcomes. Some other studies suggest that swallowing therapy within one year of completion of radiotherapy delivers the most consistent improvements when compared with a later start of swallowing therapy.

Swallowing assessments

A comprehensive assessment of dysphagia includes instrumental (‘objective’) and non-instrumental (‘subjective’) components contributing to the overall assessment of the signs & symptoms of someone’s dysphagia. Medical history and medical examination(s) are the starting point, in particular oral examinations (for example, observation of salivary flow or examination of sensation) and assessment of airway protection, coughing reflex & strength. Somebody’s subjective accounts of their swallowing problems are important, and need to be combined with instrumental and non-instrumental observations in order to form a comprehensive picture. This is a collaborative effort between speech and language therapist and patient.

Assessing the swallowing process typically involves a series of a standard range of food textures offered, and the associated swallowing performance being recorded. This is done both from simple observation and by fibre-optic endoscopic examination, and sometimes complemented by additional ‘barium swallow’ investigations. Fibre-optic examinations sometimes employ test food preparations that are coloured by dye to improve observation.

In these multiple ways, a comprehensive picture about lip seal, tongue mobility & control, bolus manipulation, food and/or saliva residues, swallowing and coughing reflexes, soft palate motility, airway protection can be obtained. Figure 1 is a sketch of the many structures actively involved in the mechanical aspects of swallowing. This is further illustrated in Figure 2 and Figure 3, where real-time MRI videos of swallowing in healthy volunteers show swallowing of carrot puree, and an ‘empty’ swallow, respectively.

Figure 1: Schematic of the anatomical structures supporting the mechanical aspects of swallowing. The schematic depicts a view of the central sagittal plane where the real-time MRI videos (see Figure 2 and Figure 3) are taken. An excellent series of annotated planes from MRI and CT scans of the head can be found here.
Figure 2: Real-time MRI video of a healthy volunteer swallowing carrot puree. To be published, research by A.J. Kennerley, D.A. Mitchell, A. Sebald and I. Watson.
Figure 3: Real-time MRI video of an ‘empty’ swallow (swallowing saliva) by a healthy volunteer. To be published, research by A.J. Kennerley, D.A. Mitchell, A. Sebald and I. Watson.

Recommendations based on swallowing assessments

Recommendations resulting from swallowing assessments, generally speaking cover the whole spectrum from ‘nil by mouth’, to a tailored list of interventions, to ‘no interventions required’.

Tube feeding may be recommended as the sole feeding method or to supplement insufficient oral food intake and/or to prevent aspiration, on a short- or long-term basis. Enteral feeding is the recommendation when all else has failed and there is no other option to maintain nutrition and hydration orally.

Many swallowing problems can be managed successfully by a combination of various adaptive and compensatory strategies. Adaptive approaches include the use of tools such as special spoons (for example, to deliver food directly to the back of the mouth), drinking straws, special bottles and/or bottles with special nipples (for example, to feed infants with cleft lip & palate), prosthesis, such as palatal drop prostheses or obturators. Obturators are individually designed to fill in a maxillary defect after resection, so that the oral cavity is sealed from the nasal cavity. Palatal drop prostheses (sometimes in combination with an obturator) help to make contact between the palate and a partially resected, or reconstructed tongue so that it is possible to clear a bolus from the mouth into the pharynx.

The choice of suitable and safe food textures is an important aspect of adaptive strategies. These choices, depending on the specific dysphagia, could be anything from a liquid diet, through soft and smooth food textures, all the way to diets avoiding liquids and instead using thickened fluids or jellies. Recommendations may also include the effects of food temperature on swallowing efficiency (varied food temperature, taste and temperature, increase sensory awareness in the oral cavity), and suggestions about optimal bolus size and placement in the mouth. For many maxillofacial patients with dysphagia, food choices are part of an overall strategy that includes compensatory methods (such as special swallowing manoeuvres, see below). Sometimes there is some individual choice whether somebody prefers to eat texture- and temperature-adapted foods with little attention to special swallowing techniques, or if it is preferable to employ special swallowing techniques and in this way have fewer restrictions with regard to safe food consistencies and textures (such as being able to swallow liquids safely).

Compensatory approaches are mostly special swallowing manoeuvres (see below) as well as a range of swallowing exercises (see below). Compensatory methods have to be used consistently to assure safe eating, they form part of somebody’s ‘new normal’.

Special swallowing manoeuvres

There are a number of techniques aiming to improve safety and efficiency of impaired swallowing. Some techniques simply exploit posture to improve flow & control of the bolus, and eliminate or reduce aspiration. Other techniques are modifications of the normal swallowing process.

Exploiting posture

Adopting particular postures of head and/or body can be efficient and straightforward ways to reduce, or even eliminate aspiration and to improve bolus transport. These specific postures work well for the majority of people, and it is straightforward to learn how to exploit postures for safe(r) swallowing. It has been reported that many people prefer postures over having to rely on, for example, thickened liquids.

These postures can be used on their own, or in combination with other postures and swallowing manoeuvres (see below). Our physiotherapy pages demonstrate these postures in videos as general exercises to strengthen the neck muscles.

Swallowing manoeuvres

These swallowing techniques are intended to ‘take (voluntary) control’ over parts of the oropharyngeal swallowing phase. These techniques typically require a little more training & practice to learn how to perform them properly. Once mastered, these techniques help reducing aspiration and improving swallow efficiency.

Alongside practical instructions and support in learning postures and special swallowing techniques, the resulting reassurance and generally supportive role of speech and language therapy (‘practical psychology’) gives most people the confidence to try at home and recover much of their oral food intake competence in time. Some people may be very anxious and still lack confidence to manage on their own; in such cases further interventions such as counselling or other psychological interventions may be helpful in supporting the recovery process.

Swallowing exercises

Swallowing exercises may be seen as a particular form of physiotherapy. In this regard, swallowing exercises differ slightly from swallowing manoeuvres. The latter are means to manage and mitigate some swallowing impairment, whereas swallowing exercises aim to rehabilitate swallowing ability, efficiency and safety as much as possible (for example, exercises to prevent or improve trismus are demonstrated in videos on our pages about physiotherapy). There is considerable overlap between these two categories.

The merits of swallowing exercises in general are not questioned. However, occasionally there seem to be some motivational barriers with some people to persevere with such exercises. It is debated, though, if prophylactic swallowing exercises have a long-term benefit for head & neck cancer patients undergoing radiotherapy (which, again, may be related to poor engagement) or if similar / identical long-term outcomes are achieved with a later start of swallowing exercises.

Swallowing exercises are meant to improve / rehabilitate swallowing over time, aiming to reduce in the longer term restrictions on oral food and the need for special swallowing manoeuvres – in short, the aim is to return swallowing and oral food intake functions to normal as far as is possible (but patience and perseverance are necessary). This is an important goal in that this is closely related to quality of life, as widely reported by patients and carers. Broadly, swallowing exercises can be subdivided into subgroups aiming to improve bolus manipulation, movements of tongue & jaws, tongue strength, airway protection.

Mouth opening is an obvious necessity in order to enjoy oral food intake. Trismus, difficulties with mouth opening (technically with jaw opening), can be improved by a range of exercises, some of which are demonstrated in videos on our physiotherapy pages.

Exercises to improve bolus manipulation

Essentially, these are exercises aiming to improve the mobility of the tongue specifically with a view to better manipulation of a bolus. Most of this can be practised in various different ways, using a lollipop or a small piece of marshmallow, or a small piece of gauze soaked in the preferred drink (to help with motivation (if safe to swallow liquid)…), or similar ‘objects’. Such exercises may indirectly also help to identify the optimal size and texture of the bolus that person can swallow.

It is a good idea, representing little rewards along the way, to celebrate progress made after days and weeks of practising with an appropriate, newly manageable, food treat – it is astonishing how much of a motivational kick this can provide and how much of a return to normality such small steps can represent.

Exercises to improve tongue mobility and strength

This group of exercises is designed to improve the range of motion of the oral tongue and/or the base of the tongue. The general approach is to increasingly stretch a structure to its maximum non-painful extent, hold the position for a few seconds, relax, then repeat the cycle several times. There are suitable exercises for all structures that are relevant for swallowing. It may be useful as a motivational prompt to note that studies have convincingly shown that these kinds of exercises, started early after surgery (within three months of treatment) and carried on for several months lead to significantly improved recovery of swallowing function in the longer term.

Exercises to improve airway protection

Airway protection is essential when aspiration is a problem, in order to restore safe oral food intake. Exercises that facilitate and improve voluntary airway protection can make all the difference between being able to feed oneself orally, or having to rely on enteral feeding.

Brief overview of typical maxillofacial dysphagia circumstances

A very brief overview of some dysphagia aspects in oral & maxillofacial surgery highlights the wide range of difficulties encountered in just this field, across all ages, degrees of severity, short- and long-term, and as a symptom of many different underlying conditions. Swallowing difficulties roughly correlate with the structures affected.

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