Swallowing disorder or dysphagia (loss of ability to swallow)
People with dysphagia have difficulty swallowing and may also experience pain while swallowing. Some people may be completely unable to swallow or may have trouble swallowing liquids, foods, or saliva. Eating may become a challenge. Often, dysphagia makes it difficult to take in enough calories and fluids to nourish the body.
What happens when we swallow
Swallowing is a complex process. Some 50 pairs of muscles and many nerves work to move food from the mouth to the stomach. This happens in three stages. First, the tongue moves the food around in the mouth for chewing. Chewing makes the food the right size to swallow and helps mix the food with saliva. Saliva softens and moistens the food to make swallowing easier. During this first stage, the tongue collects the prepared food or liquid, making it ready for swallowing.
The second stage begins when the tongue pushes the food or liquid to the back of the mouth, which triggers a swallowing reflex that passes the food through the pharynx (the canal that connects the mouth with the esophagus). During this stage, the larynx (voice box) closes tightly and breathing stops to prevent food or liquid from entering the lungs.
The third stage begins when food or liquid enters the esophagus, the canal that carries food and liquid to the stomach. This passage through the esophagus usually occurs in about 3 seconds, depending on the texture or consistency of the food.
What can go wrong
Dysphagia occurs when there is a problem with any part of the swallowing process. Dysphagia has many causes, but essentially any condition that weakens or damages the muscles and nerves used for swallowing may cause dysphagia by interfering with the coordination of muscles or limit sensation in the mouth and throat.
- head injury
- other nervous system disorder (Parkinson’s disease or aging)
Any one of these problems may make it hard to move food into the back of the throat and into the esophagus. Large pieces of food can be difficult to swallow and get caught in the throat or block the passage of air into the lungs. Thin fluids can also be difficult to move into the opening of the esophagus. Bits of food, liquids and normal secretions which are not swallowed normally can fall into the voice box, causing repeated coughing, and into the windpipe (trachea), which may result in lung infection (pneumonia). If the mucosa, or lining of the throat, squeezes out through a weakness in the esophageal wall, this abnormal pocket, known as a Zenker’s diverticulum, traps some swallowed food. While lying down or sleeping, a person with this problem may have undigested food regurgitate into the throat. Swallowing disorders may also include the development of a stricture, or narrowing, in the esophagus, caused by an infection, chronic irritation (acid reflux) or injury. Infants are sometimes born with abnormalities, such as tongue-tie, which can make it difficult to nurse.
A sudden difficulty in swallowing is often due to a foreign body getting stuck in the esophagus. The most common esophageal foreign body in adults are a piece of meat or bone. For children, it is coins and button batteries which can very caustic and dangerous. Most adults have other esophageal problems contributing to objects getting stuck. Dentures are a problem because they decrease sensation on the palate leading to misjudging of the size of the bolus and reduce effective chewing of solids. Also, objects usually get stuck where the esophagus is most narrow or where there is a stricture, such as a Schatzki's ring.
Finally, cancer of the head, neck, or esophagus may cause swallowing problems. Sometimes the treatment for these types of cancers can cause dysphagia.
- An ENT doctor can examine your throat with a thin flexible fiberoptic endoscope .
- Functional Endoscopic Evaluation of Swallowing (FEES) Sometimes soft foods and liquids with food coloring are swallowed while the doctor observes the swallowing process. FEES has the advantages that the equipment does not expose the patient to radiation. It allows a better assessment of neurologic status (including sensation) and gives a more detailed rendering of the anatomy than is available from other methodologies. The disadvantages of the FEES include the "blind spot" that occurs during the swallow because the throat fills with food or liquid and the throat closes during swallowing and blocks some of the view. Also, the esophagus cannot be examined.
- Other tests, including a modified barium swallow, barium esophagogram, ultrasound, manometry, can painlessly take evaluate of various aspects of swallowing. The most commonly used study is the modified barium swallow in which barium-coated solids and liquids are swallowed and videotaped for later review and analysis. The study requires the presence of a speech and language pathologist and a radiologist. The barium esophagogram is also an x-ray study using barium liquid to look at the esophagus for narrowed, diseased areas or a foreign body.
Once the cause of the dysphagia is found, surgery or medication may help. If treating the cause of the dysphagia does not help, the doctor may have the patient see a speech-language pathologist who may teach the person new ways to swallow.
Treatment may involve exercises to strengthen weak facial muscles or to improve coordination or learning to eat in a special way. For example, some people may have to eat with their head turned to one side or looking straight ahead, while others are advised about preparing food in a certain way or avoiding certain foods. Those who cannot swallow liquids may need to add special thickeners to their drinks, while others may have to puree their solid foods.
For some, however, consuming foods and liquids by mouth may no longer be possible. These individuals must use other methods to nourish their bodies. Usually this involves a feeding system, such as a feeding tube, that bypasses the part of the swallowing mechanism that is not working normally.