Mealtime Partners, Inc.

Specializing in Assistive Dining and Drinking Equipment

May 2015 Independent Eating and Drinking Newsletter

	May Topics: The Effect of Thickening Liquids and Modifying the Texture of Food on Swallowing We Want Your Help on Choking Prevention Procedures
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The Effect of Thickening Liquids and Modifying the Texture of Food on Swallowing

Thickening liquids and modifying the texture of foods is the standard protocol throughout the world for treating individuals with swallowing difficulties who are at risk of choking or aspiration. This article will discuss the ramifications of changing liquid and solid texture and discuss shortcomings within the current research that has been conducted about the impact of diet texture changes.

Over time, clinical practice has incorporated both thickening of liquids and texture modification of food as the gold standard for treatment for individuals who have swallowing impairments. However, the current guidelines for the use of thickening agents for liquids and for chopping, mincing, or pureeing food, only provide limited instructions about how they should be used. This can sometimes lead to misunderstanding and incorrect use on the part of care providers.

The International Dysphagia Diet Standardization Initiative (IDDSI) was established to develop standardized terminology and definitions for texture-modified foods and thickening liquids across setting and cultures. The organization is currently finalizing a seven level liquid to solids texture scale on which they are currently seeking feedback. To participate please go to their website http://iddsi.org/, and take their survey. You will be given an opportunity to provide feedback to them about this measurement standard.

Over the past several decades, many studies have been conducted to evaluate the benefits of thickening liquids and modifying food texture for those individuals who have swallowing difficulties. Different methodologies have been used to measure the impact of modified textures on the swallow process. The findings generally indicate that the changes produce a slower swallow rate and an associated reduction in the risk of penetration aspiration. However, though there is a reduced risk of aspiration as the thickness of the items consumed increases, there is an associated risk of food/liquid residue remaining in the pharynx after the swallow. Because of the risk of post-swallow residue that is associated with very thick liquid/food, the level of thickening prescribed for an individual with swallowing difficulties should be the least possible to avoid them aspirating (instead of erring on the side of over thickening as a precaution).

Depending upon which thickening agent is used to thicken liquids, and the specific liquid that is being thickened, the viscosity, and cohesiveness can be different.  Two agents are commonly used in commercial thickening products and commercially prepared texture modified foods: corn starch, and xantham-gum. Because the two agents do not perform in exactly the same way it cannot be assumed that the same food or liquid thickened with different thickening agents will behave the same when put in the mouth and swallowed. Additionally, a very small increase or decrease in the viscosity of what is being thickened is hard to perceive and yet may make a difference to the manageability when being swallowed.

Many of the studies that evaluate swallowing performance use videofluoroscopic examination (VFE) to evaluate the impact of the bolus consistency upon the swallow. To be able to conduct this type of evaluation, the participant must consume barium laced food or liquid. Barium also changes the viscosity, texture and density of what is being consumed. Therefore, it is impossible to exactly replicate the “thickness” of food or liquid in real life situations as compared with items used during VFE.

To further complicate matters, many foods change their texture as they are eaten or drunk, and some require more tongue pressure and/or chewing to be broken down than other foods. Therefore, viscosity cannot be the only characteristic of what is being consumed that is considered. The branch of physics that studies fluids and the effect of force on them is called fluid mechanics. The field can be divided into two parts: the study of fluid at rest, fluid statics; and fluid dynamics, which is the study of liquid in motion. This is important as it relates to how liquids behave when eaten (the term liquids, does not only apply to drinks but also to foods like pudding or pureed food). Water and similar liquids behave in a predicable way that is linear and the viscosity is constant as long as it remains a liquid. When it is in a glass, it flows into the mouth at the same rate as when it is swallowed after being drunk. When liquid is “treated” with thickening agents, it no longer behaves in this predictable way. When thickened liquids, and many different food products, are put under stress (e.g., chewed or pressed against the roof of the mouth by the tongue), the viscosity of the product changes. The force placed upon the material by the muscles in the mouth changes it. Depending upon the material, the time that the force must be applied before the change takes place varies. The pressure and movement of the tongue on materials when they are eaten, can change them from solid to liquid. The question arises: are they a solid or a liquid? Peanut butter and cheese spread are examples of food items where this question applies. Additionally, the mixing of saliva with these items contributes to the speed at which they change their characteristics.

In basic terms, when material is put in the mouth, the muscles in the mouth move it around in the oral cavity mixing it with saliva while it is being manipulated. The material will be moved to the back of the mouth by the action of the tongue pushing against the roof of the mouth. In the case of water or similar liquids, they may flow to the back of the throat without the tongue pushing them. Once the material is at the back of the throat, a swallow is initiated. Some materials change from solid to liquid during this process. For example, thick pudding will liquefy as it is moved around in the mouth.

Because thin liquid flows with gravity, it is more difficult to control its movement in the mouth and to manage the process of it moving to the back of the mouth in a controlled manner. Therefore, people who have swallowing difficulties may need to avoid thin liquids. When control of thin liquid is limited, it may move too quickly to the back of the throat and start its decent into the esophagus. When this occurs, the swallow process might start too quickly and the body may not have the time to protect the trachea.  Thus the material can pass into the breathing tube rather than the esophagus, causing choking or aspiration.

Other problems that must be considered relating to safe swallowing relate to the mouth and its musculature. Weakened muscles are less able to chew, manipulate and control food or liquid in the mouth. It is easy for particles of material to be “lost” in the oral cavity and not formed into a bolus and swallowed. Also, fatigue is a factor that must be considered when muscles are weak. Chewing and breaking down food with the teeth is hard work. Modifying the texture of foods and thickening liquids can lessen the burden that eating places on the individual, making meals easier to consume without the concern that they may cause choking.

Poor fitting dentures, poor oral health, and tooth cavities create an additional problem for chewing. If dentures do not fit well, it is hard to chew and control food in the mouth. Cavities and oral health problems cause pain which makes eating and drinking difficult. Posture while eating and drinking is also a contributing factor to how safely someone with swallowing difficulties is able to eat and drink. Attention must always be paid to the individual’s position while eating regardless of the texture of their meal.

Finally, it should be remembered that if an individual is unable to self-feed, studies have shown that their risk of choking or aspiration is increased. A dining device like the Mealtime Partner can serve regular textured food as well as all levels of texture modified foods. Using assistive technology to provide independent eating allows the individual who is feeding themselves to control their pace of eating and is a lot safer than being fed (and a great deal more pleasant). Click on the following link for more information about the Mealtime Partner Dining System. 

 

The Mealtime Partner Dining System
For those who have a spinal cord injury, cerebral palsy, tremors, or another illness or disease preventing them from feeding themselves, the Mealtime Partner can provide mealtime independence allowing a pleasant dining experience that is totally under the control of the individual eating.
The Mealtime Partner Dining System can be positioned to meet the specific needs of each user. The user does not have to adjust their position to eat using the device because the Mealtime Partner’s flexible mounting systems permit positioning to fit the user's needs, making mealtimes a comfortable, relaxed experience, with the user positioned safely for eating. The Mealtime Partner empowers its user to eat what they want, when they want it. The Mealtime Partner Dining System is quick and easy to learn and has no complicated programming requirements. Each Dining System comes with a complete training video on DVD so new users and caregivers can learn to use it in just a few minutes. (Many of the training videos can be found on our website at Training). For more information about the Mealtime Partner Dining System, please visit Mealtime Partners website. There is no other assistive dining system that meets the needs of the users, like the Mealtime Partner.

 We Want Your Help on Choking Prevention Procedures

The risk of choking and/or aspiration exists for everyone. However, for people with disabilities the risk is often higher than their able bodied counterparts. The typical treatment when choking occurs is to perform the Heimlich maneuver. However, this is not necessarily an easy solution to accomplish when someone is sitting in a wheelchair when they choke, with a lap-belt and shoulder or chest harness holding them in position. There are many policies and procedures in existence that provide guidelines as to what action should be taken when choking occurs and the person who is choking is sitting in their wheelchair. However, the guidelines that Mealtime Partners is aware of differ significantly and vary from state to state and facility to facility. In an effort to develop the most appropriate recommendations Mealtime Partners is planning to compile a report that describes policies and procedures that are currently being used. We would like the report to be comprehensive and yet have had difficulties finding instructions when general searches have been conducted. Therefore we are reaching out to our readers for assistance.

If you are aware of a document that provides instructions about the actions that should be taken when someone who is sitting in a wheelchair chokes, please send a website link to the document, or send a copy of the document by email to: choking@mealtimepartners.com. (If you would like to be credited with providing the document please provide you name, title, and organization name and give us permission to include your information.)

Once all the information that we can identify has been reviewed and cataloged we will make the document available on our website and provide a link to the material in a future Newsletter. Links to all of the resource material that is in the report will also be available.

Any other information or feedback on this subject would be welcomed. This is an area of concern to many people who are responsible for feeding individuals who sit in their wheelchair while eating. The level of difficulty in handling this situation varies significantly depending upon the level of dependency of the individual.

In advance, thank you very much for your help.

Did You Know? Did you know that scientists at the Monell Chemical Senses Center have discovered that our immune system regulates our sensitivity to bitter taste? A protein that regulates the immune system called tumor necrosis factor (TNF) also is responsible for our sensing bitterness. TNF regulates inflammation in our bodies and when inflammation increases, TNF also alters the level of awareness to bitterness that we sense. This phenomenon may make food and liquid taste bad when someone is ill, and thus the individual may reduce their intake of food and liquid. This can result in malnutrition in those who have a long term illness. Researchers are studying whether TNF is responsible for reducing the appetite because of its impact on taste. Further information about this area of study can be found by clicking here.