Human Digestive system - Dysphagia

Dysphagia

 Dysphagia means difficulty swallowing. Odynophagia means painful swallowing. Sometimes it is not easy for individuals to distinguish between these two problems. For example, food that sticks in the esophagus can be painful. Is this dysphagia or odynophagia or both? Technically it is dysphagia, but individuals may describe it as painful swallowing (odynophagia). Nevertheless, it is important to distinguish between the two because the causes of each may be quite different. When dysphagia is mild it may cause an individual only to stop eating for a minute or less, but when it is severe it can prevent an individual from taking in enough calories for adequate nutrition. Some conditions associated with dysphagia affect the area of the lower throat, primarily conditions in which there are abnormalities of nerves or muscles that control the throat. This area also is the area from which the trachea, the main airway leading to the lungs, begins. As a result, abnormalities with the function of the nerves and muscles of this area can lead to discoordination and, in passing; food may be more easily aspirated into the lungs, potentially leading to bacterial infection and a form of pneumonia known as aspiration pneumonia.

Dysphagia Causes

The process of swallowing has three stages.

  1. The first stage of swallowing begins in the mouth, where the tongue helps move the food around inside the mouth so that it can be chewed and softened with saliva. The tongue also is necessary for propelling the food to the back of the mouth and upper throat (pharynx) initiating the second stage.

  2. The second stage of swallowing, is an automatic reflex that causes the muscles of the throat to propel the food through the throat (pharynx) and into the esophagus or swallowing tube. A muscular valve that lies between the lower throat and the top of the esophagus opens, allowing the food to enter the esophagus, while other muscles close the opening to the trachea to prevent food from entering the trachea and the lungs.
  3. The third stage of swallowing begins when food or liquid enters the esophagus. The esophagus is a muscular tube that connects the throat to the stomach and uses coordinated contractions of its muscles to push the food down its length and into the stomach. A second muscular valve opens at the junction of the lower esophagus with the stomach once a swallow has begun to allow the swallowed food to enter the stomach. After the food passes the valve closes again, preventing the food from regurgitating back up into the esophagus from the stomach.

Dysphagia has many causes. First, there may be physical (anatomical) obstruction to the passage of food. Second, there may be abnormalities in the function (functional abnormalities) of the nerves of the brain, throat, and esophagus whose normal function is necessary to coordinate swallowing. Finally, there also may be abnormalities of the muscles of the throat and esophagus themselves. Diseases of the brain can affect the neurological control of the nerves and reflexes involved in swallowing. Some diseases of the brain that can cause dysphagia include: stroke, amyotropic lateral sclerosis, Parkinson`s disease, multiple sclerosis, head injury, and cerebral palsy. Likewise, diseases and conditions that affect muscle function or connective tissue throughout the body can cause dysphagia. Examples include: muscular dystrophy, dermatomyositis, myasthenia gravis, scleroderma (systemic sclerosis), and Sjogren`s syndrome. Diseases specific to the esophagus also can cause difficulty swallowing. Some esophageal diseases include: achalasia, a rare inability of the lower esophageal sphincter (the valve at the lower end of the esophagus) to open and let food pass into the stomach and disappearance of the contractions of the esophagus that propel food; eosinophilic esophagitis, an inflammatory condition of the esophagus in which the esophageal wall is filled with a type of white blood cell called eosinophils; and other functional abnormalities of the muscle of the esophageal muscle including spasm and ineffective contractions. Obstructions of the upper digestive tract and esophagus, due to anatomical abnormalities, tumors, or scar tissue also cause dysphagia. Examples include: esophageal cancer; esophagitis (inflammation of the esophagus) though the symptom of esophagitis is more commonly odynophagia; certain head and neck cancers; esophageal strictures (narrowings of the esophagus) that result from inflammation and scarring most commonly from chronic acid exposure due to acid reflux, but they also may arise due to radiation, medications, or chemical toxins; Schatzki rings (smooth, benign, circumferential, and narrow rings of tissue in the lower end of the esophagus that are located just above the junction of the esophagus with the stomach); compression of the esophagus from structures outside of the digestive tract, such as tumors of the chest, aortic aneurysms, enlarged lymph nodes, etc.; and congenital anatomical abnormalities (birth defects).

Dysphagia Symptoms

Depending upon the cause of the dysphagia, the difficulty swallowing can be mild or severe. Some affected individuals may have trouble swallowing both solids and liquids, while others may experience problems only when attempting to swallow solid foods. Occasionally, there is more trouble with liquid than solid food. If there is aspiration of food (most common with liquids), swallows may induce coughing due to entrance of the liquid into the voice box (larynx) or lungs. If solid food becomes lodged in the lower throat, it may induce choking and gagging and interfere with breathing. If solid food lodges in the esophagus, it may be felt as severe chest discomfort. Finally and less commonly, swallowed food may regurgitate effortlessly into the mouth immediately after it is swallowed. If dysphagia is associated with aspiration of food into the lungs, aspiration pneumonia may occur with all of the symptoms of pneumonia (fever, chills, and respiratory distress). Other symptoms associated with dysphagia depend upon its exact cause and are specific to the condition that results in dysphagia, such as stroke, cancer, etc.

Exams and Tests

The evaluation of dysphagia begins with a complete medical history and physical examination. When taking the medical history, health care practitioner will ask questions regarding the duration, onset, and severity of symptoms as well as the presence of associated symptoms or chronic medical conditions that can help determine the cause of the dysphagia. Some specific diagnostic tests are frequently performed to evaluate the esophagus and its function: An esophagram or barium swallow is an imaging test used to visualize the structures of the esophagus. The patient swallows liquid barium while X-ray images are obtained. The barium fills and then coats the lining of the esophagus. Videofluoroscopy is an alternative test to the barium swallow that uses video X-ray images of the swallowing process. It is better able to evaluate the more subtle muscular abnormalities that can affect swallowing than the barium swallow. Endoscopy may be carried out to visualize the lining of the esophagus and stomach, if necessary. Esophageal manometry studies can measure the pressure generated by the muscle contractions in the esophagus using a pressure-sensitive, thin tube that is passed into the esophagus through the nose. This test can determine if the muscles of the esophagus are working properly. Esophageal pH studies may be performed in patients with suspected acid reflux (gastroesophageal reflux disease or GERD). For the pH study, a thin catheter that records pH (acidity) is inserted into the esophagus through the nose. This allows acid reflux to be measured and correlated with symptoms such as heartburn over a prolonged period of time. Similar measurements and correlations can be made without a catheter by attaching a small capsule to the esophageal wall that measures acidity and wirelessly transmits the measurements to a recorder carried at the waist. A fiberoptic endoscopic examination of swallowing (FEES) or transnasal laryngoscopy is another test that may be used. In this study, a laryngoscope is inserted through the nose to visually evaluate the swallowing process in the pharynx. Since dysphagia can be caused by a multitude of different medical conditions, further diagnostic testing will depend upon the patient`s medical history and the information derived from the physical examination and from any tests that have been done to evaluate swallowing.

Dysphagia Treatment

The treatment of dysphagia can involve both medical and surgical procedures, and depends upon the underlying condition or reason for the dysphagia. For example, treatment may be directed at an underlying condition such as cancer or stricture due to GERD. Treatment goals are to improve swallowing, to reduce the risk of aspiration, and/or to improve the nutritional status of the affected individual Self-Care at Home Depending upon the individual situation, dietary modifications may be a necessary step in the treatment of dysphagia. A soft or pureed diet may be recommended. Physical therapy may be an important component of treatment for some patients. Physical therapy and rehabilitation measures may include recommendations such as: changing the head position while eating, exercises that retrain the musculature involved with swallowing, or strength and coordination exercises for the tongue. A speech-language pathologist may be a member of the evaluation and treatment team and can be of help in prescribing rehabilitation exercises for the muscles of the mouth and tongue. If the individual has symptoms of gastroesophageal reflux (GERD), avoidance of eating prior to bedtime, smoking cessation, maintaining an upright posture after eating, and certain medications (see below) may help relieve symptoms

Medical Treatment and Medications

Symptoms of GERD, such as heartburn, if present, are treated with medications designed to reduce acid levels in the stomach. These can include: antacids; H2 blockers such as nizatidine (Axid), famotidine (Pepcid), cimetidine (Tagamet), or ranitidine (Zantac); and proton pump inhibitor drugs, such as esomeprazole, lansoprazole , omeprazole, pantoprazole, or rabeprazole. Patients with achalasia or other motility disorders of the esophagus can be treated with medications that help to relax the lower esophageal sphincter. These include the nitrate class of drugs, for example, isosorbide dinitrate (Isordil) and calcium-channel blockers, for example, nifedipine (Procardia) and verapamil (Calan). These drugs, however, are not very effective. A more recently developed treatment for some types of dysphagia associated with esophageal muscle problems caused by spasm is the endoscopic injection of botulinum toxin (Botox), for example, into the lower esophageal sphincter to weaken the sphincter in achalasia. Treatment with botulinum toxin is safe, but the effects on the sphincter often last only for months, and additional injections are necessary. Corticosteroids are the treatment for dysphagia caused by eosinophilic esophagitis.

Surgery

Some anatomical abnormalities of the oropharynx or esophagus that cause dysphagia can be treated successfully by surgery. Surgery is also a component of treatment for dysphagia associated with esophageal cancer and compression of the esophagus due to other tumors or abnormalities in the chest. Surgical treatments for dysphagia are varied. The choice of procedure depends upon the cause of dysphagia. Dilation of the lower esophageal sphincter in achalasia is done by having the patient swallow a tube with a balloon on the end that is positioned across the lower esophageal sphincter with the help of X-ray, and the balloon is blown up suddenly. The goal is to stretch - actually to tear - the sphincter. This also can be useful in treatment of strictures and Schatzki rings as well as other anatomical conditions associated with dysphagia. The lower esophageal sphincter also can be cut surgically in a procedure called esophagomyotomy. The surgery can be done using a large abdominal incision or laparoscopically through small punctures in the abdomen or chest. Other surgical procedures depend upon the exact location and extent of the anatomical abnormality that is causing the dysphagia. Surgical procedures may also be necessary to increase a patient`s nutritional status in cases of severe dysphagia. A nasogastric (NG) tube is used for feeding when the condition is not expected to present a long-term problem. For chronic cases of severe dysphagia, a percutaneous endoscopic gastrostomy (PEG) tube can be inserted surgically directly through the skin into the stomach in order to deliver food directly into the stomach.

Follow-up

Follow-up recommendations depend upon the cause of the dysphagia and the type of treatment that has been performed. It is important to keep all follow-up appointments and follow the instructions of the health care provider.