Dysphagia

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Dysphagia
Tractus intestinalis esophagus.svg
The digestive tract, with the esophagus marked in red
Specialty Gastroenterology, phoniatrics
Symptoms Inability or difficulty swallowing
Complications Pulmonary aspiration, malnutrition, starvation
Causes Esophageal cancer, Esophagitis, Stomach cancer, mental illness, alcoholism, refeeding syndrome, starvation, infection, gastritis, malnutrition

Dysphagia is difficulty in swallowing. [1] [2] Although classified under "symptoms and signs" in ICD-10, [3] in some contexts it is classified as a condition in its own right. [4] [5] [6]

Contents

It may be a sensation that suggests difficulty in the passage of solids or liquids from the mouth to the stomach, [7] a lack of pharyngeal sensation or various other inadequacies of the swallowing mechanism. Dysphagia is distinguished from other symptoms including odynophagia, which is defined as painful swallowing, [8] and globus, which is the sensation of a lump in the throat. A person can have dysphagia without odynophagia (dysfunction without pain), odynophagia without dysphagia (pain without dysfunction) or both together. A psychogenic dysphagia is known as phagophobia. [9]

Classification

Dysphagia is classified into the following major types: [10]

  1. Oropharyngeal dysphagia
  2. Esophageal and obstructive dysphagia
  3. Neuromuscular symptom complexes
  4. Functional dysphagia is defined in some patients as having no organic cause for dysphagia that can be found.

Signs and symptoms

Some patients have limited awareness of their dysphagia, so lack of the symptom does not exclude an underlying disease. [11] When dysphagia goes undiagnosed or untreated, patients are at a high risk of pulmonary aspiration and subsequent aspiration pneumonia secondary to food or liquids going the wrong way into the lungs. Some people present with "silent aspiration" and do not cough or show outward signs of aspiration. Undiagnosed dysphagia can also result in dehydration, malnutrition, and kidney failure. [12]

Some signs and symptoms of oropharyngeal dysphagia include difficulty controlling food in the mouth, inability to control food or saliva in the mouth, difficulty initiating a swallow, coughing, choking, frequent pneumonia, unexplained weight loss, gurgly or wet voice after swallowing, nasal regurgitation, and patient complaint of swallowing difficulty. [11] When asked where the food is getting stuck, patients will often point to the cervical (neck) region as the site of the obstruction. The actual site of obstruction is always at or below the level at which the level of obstruction is perceived.[ citation needed ]

The most common symptom of esophageal dysphagia is the inability to swallow solid food, which the patient will describe as 'becoming stuck' or 'held up' before it either passes into the stomach or is regurgitated. Pain on swallowing or odynophagia is a distinctive symptom that can be highly indicative of carcinoma, although it also has numerous other causes that are not related to cancer. Achalasia is a major exception to usual pattern of dysphagia in that swallowing of fluid tends to cause more difficulty than swallowing solids. In achalasia, there is idiopathic destruction of parasympathetic ganglia of the Auerbach's (Myenteric) plexus of the entire esophagus, which results in functional narrowing of the lower esophagus, and peristaltic failure throughout its length. [13]

Complications

Complications of dysphagia may include aspiration, pneumonia, dehydration, and weight loss. [14]

Causes

The following table enumerates possible causes of dysphagia:

Difficulty with or inability to swallow may be caused or exacerbated by usage of opiate and/or opioid drugs. [15]

Diagnosis

Differential diagnosis

All causes of dysphagia are considered as differential diagnoses. Some common ones are: [17]

Esophageal dysphagia is almost always caused by disease in or adjacent to the esophagus but occasionally the lesion is in the pharynx or stomach. In many of the pathological conditions causing dysphagia, the lumen becomes progressively narrowed and indistensible. Initially, only fibrous solids cause difficulty but later the problem can extend to all solids and later even to liquids. Patients with difficulty swallowing may benefit from thickened fluids if the person is more comfortable with those liquids, although, so far, there is no scientific study that proves that those thickened liquids are beneficial. [22]

Dysphagia may manifest as the result of autonomic nervous system pathologies including stroke [23] and ALS, [24] or due to rapid iatrogenic correction of an electrolyte imbalance. [25]

In older adults, presbyphagia - the normal healthy changes in swallowing associated with age - should be considered as an alternative explanation for symptoms. [26]

Treatments

There are many ways to treat dysphagia, such as swallowing therapy, dietary changes, feeding tubes, certain medications, and surgery. Treatment for dysphagia is managed by a group of specialists known as a multidisciplinary team. Members of the multidisciplinary team include: a speech language pathologist specializing in swallowing disorders (swallowing therapist), primary physician, gastroenterologist, nursing staff, respiratory therapist, dietitian, occupational therapist, physical therapist, pharmacist, and radiologist. [11] The role of the members of the multidisciplinary team will differ depending on the type of swallowing disorder present. For example, the swallowing therapist will be directly involved in the treatment of a patient with oropharyngeal dysphagia, while a gastroenterologist will be directly involved in the treatment of an esophageal disorder.[ citation needed ]

Treatment strategies

The implementation of a treatment strategy should be based on a thorough evaluation by the multidisciplinary team. Treatment strategies will differ on a patient to patient basis and should be structured to meet the specific needs of each individual patient. Treatment strategies are chosen based on a number of different factors including diagnosis, prognosis, reaction to compensatory strategies, severity of dysphagia, cognitive status, respiratory function, caregiver support, and patient motivation and interest. [11]

Oral vs. nonoral feeding

Adequate nutrition and hydration must be preserved at all times during dysphagia treatment. The overall goal of dysphagia therapy is to maintain or return the patient to, oral feeding. However, this must be done while ensuring adequate nutrition and hydration and a safe swallow (no aspiration of food into the lungs). [11] If oral feeding results in increased mealtimes and increased effort during the swallow, resulting in not enough food being ingested to maintain weight, a supplementary nonoral feeding method of nutrition may be needed. In addition, if the patient aspirates food or liquid into the lungs despite the use of compensatory strategies, and is therefore unsafe for oral feeding, nonoral feeding may be needed. Nonoral feeding includes receiving nutrition through a method that bypasses the oropharyngeal swallowing mechanism including a nasogastric tube, gastrostomy, or jejunostomy. [11] Some people with dysphagia, especially those nearing the end of life, may choose to continue eating and drinking orally even when it has been deemed unsafe. This is known as "risk feeding". [27]

Swallowing difficulties in dementia

A 2018 Cochrane review found no certain evidence about the immediate and long-term effects of modifying the thickness of fluids for swallowing difficulties in people with dementia. [28] While thickening fluids may have an immediate positive effect on swallowing and improving oral intake, the long-term impact on the health of the person with dementia should also be considered. [22]

Treatment procedures

Compensatory treatment procedures are designed to change the flow of the food/liquids and eliminate symptoms but do not directly change the physiology of the swallow. [11]

  • Postural techniques
  • Food consistency (diet) changes
  • Modifying volume and speed of food presentation
  • Technique to improve oral sensory awareness
  • Intraoral prosthetics

Therapeutic treatment procedures – designed to change and/or improve the physiology of the swallow. [11] [29]

  • Oral and pharyngeal range-of-Motion exercises
  • Resistance exercises
  • Bolus control exercises
  • Swallowing maneuvers
    • Supraglottic swallow
    • Super-supraglottic swallow
    • Effortful swallow
    • Mendelsohn maneuver

Patients may need a combination of treatment procedures to maintain a safe and nutritionally adequate swallow. For example, postural strategies may be combined with swallowing maneuvers to allow the patient to swallow in a safe and efficient manner.[ citation needed ]

The most common interventions used for those with oropharyngeal dysphagia by speech language pathologists are rehabilitation of the swallow through oral motor exercises, texture modification of foods, thickening fluids and positioning changes during swallowing. [30] The effectiveness of modifying food and fluid in preventing aspiration pneumonia has been questioned and these can be associated with poorer nutrition, hydration and quality of life. [31] Also, there has been considerable variability in national approaches to describing different degrees of thickened fluids and food textures.  However, in 2015, the International Dysphagia Diet Standardisation Initiative (IDDSI) group produced an agreed IDDSI framework consisting of a continuum of 8 levels (0–7), where drinks are measured from Levels 0 – 4, while foods are measured from Levels 3 – 7. [32] It is likely that this initiative, which has widespread support among dysphagia practitioners, will improve communication with carers and will lead to greater standardisation of modified diets[ citation needed ]

Epidemiology

Swallowing disorders can occur in all age groups, resulting from congenital abnormalities, structural damage, and/or medical conditions. [11] Swallowing problems are a common complaint among older individuals, and the incidence of dysphagia is higher in the elderly, [33] [34] and in patients who have had strokes. [35] Dysphagia affects about 3% of the population. [36]

Etymology

The word "dysphagia" is derived from the Greek dys meaning bad or disordered, and the root phag- meaning "eat".[ citation needed ]

See also

Related Research Articles

<span class="mw-page-title-main">Esophageal achalasia</span> Rare, incurable, progressive motility disorder due to failure of esophogeal motor neurons

Esophageal achalasia, often referred to simply as achalasia, is a failure of smooth muscle fibers to relax, which can cause the lower esophageal sphincter to remain closed. Without a modifier, "achalasia" usually refers to achalasia of the esophagus. Achalasia can happen at various points along the gastrointestinal tract; achalasia of the rectum, for instance, may occur in Hirschsprung's disease. The lower esophageal sphincter is a muscle between the esophagus and stomach that opens when food comes in. It closes to avoid stomach acids from coming back up. A fully understood cause to the disease is unknown, as are factors that increase the risk of its appearance. Suggestions of a genetically transmittable form of achalasia exist, but this is neither fully understood, nor agreed upon.

Heller myotomy is a surgical procedure in which the muscles of the cardia are cut, allowing food and liquids to pass to the stomach. It is used to treat achalasia, a disorder in which the lower esophageal sphincter fails to relax properly, making it difficult for food and liquids to reach the stomach.

An esophageal motility disorder (EMD) is any medical disorder resulting from dysfunction of the coordinated movement of esophagus, which causes dysphagia.

Swallowing, also called deglutition or inglutition in scientific contexts, is the process in the body of a human or other animal that allows for a substance to pass from the mouth, to the pharynx, and into the esophagus, while shutting the epiglottis. Swallowing is an important part of eating and drinking. If the process fails and the material goes through the trachea, then choking or pulmonary aspiration can occur. In the human body the automatic temporary closing of the epiglottis is controlled by the swallowing reflex.

<span class="mw-page-title-main">Pulmonary aspiration</span> Entry of materials into the larynx (voice box) and lower respiratory tract

Pulmonary aspiration is the entry of material such as pharyngeal secretions, food or drink, or stomach contents from the oropharynx or gastrointestinal tract, into the larynx and lower respiratory tract, the portions of the respiratory system from the trachea (windpipe) to the lungs. A person may inhale the material, or it may be delivered into the tracheobronchial tree during positive pressure ventilation. When pulmonary aspiration occurs during eating and drinking, the aspirated material is often colloquially referred to as "going down the wrong pipe".

<span class="mw-page-title-main">Feeding tube</span> Medical device used to provide nutrition to people

A feeding tube is a medical device used to provide nutrition to people who cannot obtain nutrition by mouth, are unable to swallow safely, or need nutritional supplementation. The state of being fed by a feeding tube is called gavage, enteral feeding or tube feeding. Placement may be temporary for the treatment of acute conditions or lifelong in the case of chronic disabilities. A variety of feeding tubes are used in medical practice. They are usually made of polyurethane or silicone. The outer diameter of a feeding tube is measured in French units. They are classified by the site of insertion and intended use.

<span class="mw-page-title-main">Plummer–Vinson syndrome</span> Medical condition

Plummer–Vinson syndrome is a rare disease characterized by difficulty swallowing, iron-deficiency anemia, glossitis, cheilosis and esophageal webs. Treatment with iron supplementation and mechanical widening of the esophagus generally provides an excellent outcome.

<span class="mw-page-title-main">Esophageal web</span> Abnormal membrane in the esophagus

Esophageal webs are thin membranes occurring anywhere along the esophagus.

<span class="mw-page-title-main">Megaesophagus</span> Medical condition

Megaesophagus, also known as esophageal dilatation, is a disorder of the esophagus in humans and other mammals, whereby the esophagus becomes abnormally enlarged. Megaesophagus may be caused by any disease which causes the muscles of the esophagus to fail to properly propel food and liquid from the mouth into the stomach. Food can become lodged in the flaccid esophagus, where it may decay, be regurgitated, or maybe inhaled into the lungs.

Thickened fluids and thickened drinks are often used for people with dysphagia, a disorder of swallowing function. The thicker consistency makes it less likely that individuals will aspirate while they are drinking. Individuals with difficulty swallowing may find that liquids cause coughing, spluttering, or even aspiration, and that thickening drinks enables them to swallow safely. Patients may be advised to consume thickened liquids after being extubated. Liquid thickness may be measured by two methods, with a viscometer or by line spread test.

<span class="mw-page-title-main">Aspiration pneumonia</span> Medical condition

Aspiration pneumonia is a type of lung infection that is due to a relatively large amount of material from the stomach or mouth entering the lungs. Signs and symptoms often include fever and cough of relatively rapid onset. Complications may include lung abscess, acute respiratory distress syndrome, empyema, and parapneumonic effusion. Some include chemical induced inflammation of the lungs as a subtype, which occurs from acidic but non-infectious stomach contents entering the lungs.

<span class="mw-page-title-main">Esophagectomy</span>

Esophagectomy or oesophagectomy is the surgical removal of all or parts of the esophagus.

<span class="mw-page-title-main">Eosinophilic esophagitis</span> Allergic inflammatory condition of the esophagus

Eosinophilic esophagitis (EoE) is an allergic inflammatory condition of the esophagus that involves eosinophils, a type of white blood cell. In healthy individuals, the esophagus is typically devoid of eosinophils. In EoE, eosinophils migrate to the esophagus in large numbers. When a trigger food is eaten, the eosinophils contribute to tissue damage and inflammation. Symptoms include swallowing difficulty, food impaction, vomiting, and heartburn.

<span class="mw-page-title-main">Oropharyngeal dysphagia</span> Difficulty controlling the mouth or throat for swallowing

Oropharyngeal dysphagia is the inability to empty material from the oropharynx into the esophagus as a result of malfunction near the esophagus. Oropharyngeal dysphagia manifests differently depending on the underlying pathology and the nature of the symptoms. Patients with dysphagia can experience feelings of food sticking to their throats, coughing and choking, weight loss, recurring chest infections, or regurgitation. Depending on the underlying cause, age, and environment, dysphagia prevalence varies. In research including the general population, the estimated frequency of oropharyngeal dysphagia has ranged from 2 to 16 percent.

Esophageal dysphagia is a form of dysphagia where the underlying cause arises from the body of the esophagus, lower esophageal sphincter, or cardia of the stomach, usually due to mechanical causes or motility problems.

<span class="mw-page-title-main">Globus pharyngis</span> "Lump in the throat" sensation

Globus pharyngis, globus hystericus or globus sensation is the persistent but painless sensation of having a pill, food bolus, or some other sort of obstruction in the throat when there is none. Swallowing is typically performed normally, so it is not a true case of dysphagia, but it can become quite irritating. It is common, with 22–45% of people experiencing it at least once in their lifetime.

Pseudodysphagia, in its severe form, is the irrational fear of swallowing or, in its minor form, of choking. The symptoms are psychosomatic, so while the sensation of difficult swallowing feels authentic to the individual, it is not based on a real physical symptom. It is important that dysphagia be ruled out before a diagnosis of pseudodysphagia is made.

<span class="mw-page-title-main">Nutcracker esophagus</span> Medical condition

Nutcracker esophagus, jackhammer esophagus, or hypercontractile peristalsis, is a disorder of the movement of the esophagus characterized by contractions in the smooth muscle of the esophagus in a normal sequence but at an excessive amplitude or duration. Nutcracker esophagus is one of several motility disorders of the esophagus, including achalasia and diffuse esophageal spasm. It causes difficulty swallowing, or dysphagia, with both solid and liquid foods, and can cause significant chest pain; it may also be asymptomatic. Nutcracker esophagus can affect people of any age but is more common in the sixth and seventh decades of life.

<span class="mw-page-title-main">Aphagia</span> Medical condition

Aphagia is the inability or refusal to swallow. The word is derived from the Ancient Greek prefix α, meaning "not" or "without," and the suffix φαγία, derived from the verb φαγεῖν, meaning "to eat." It is related to dysphagia which is difficulty swallowing, and odynophagia, painful swallowing. Aphagia may be temporary or long term, depending on the affected organ. It is an extreme, life-threatening case of dysphagia. Depending on the cause, untreated dysphagia may develop into aphagia.

<span class="mw-page-title-main">Achalasia microcephaly</span> Medical condition

Achalasia microcephaly syndrome is a rare condition whereby achalasia in the oesophagus manifests alongside microcephaly and intellectual disability. This is a rare constellation of symptoms with a predicted familial trend.

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