Understanding Dysphagia

Dysphagia Definition

• Difficulty with swallowing.
• The word is derived from Greek, with "dys" meaning difficulty, and "phagein" meaning to eat.
• Dysphagia is reported in 5-8% of the population over 50 years old, and 16% of the elderly.
• Oropharyngeal dysphagia is reported in up to 60% of nursing home occupants.

Key Differentiations

• Oropharyngeal dysphagia needs to be differentiated from esophageal dysphagia.
• Esophageal dysphagia can be classified as a structural abnormality (mechanical obstruction) or a motility disorder.
• Odynophagia needs to be recognised and distinguished from dysphagia with its own differential diagnosis considerations.

Esophagus Anatomy

• The esophagus is a hollow tube connecting the pharynx to the stomach.
• It is approximately 20 cm long, 3 cm across, and 2 cm AP (anterior-posterior).
• The esophagus is lined by squamous epithelium.
• Functionally, it has three zones: the Upper Esophageal Sphincter (UES), the Body, and the Lower Esophageal Sphincter (LES).
• The UES and proximal 3-4 cm of the esophagus consist of striated muscles.
• The distal two-thirds and LES consists of smooth muscle.
• The UES is the cricopharyngeus loop to the cricoid cartilage.
• The Body of the esophagus consists of outer longitudinal and inner circular muscle.
• The LES is a high-pressure zone at the gastroesophageal (GE) junction.

Swallowing mechanism

• Chewing mixes food with saliva, exposes it to salivary amylase, and reduces particle size to facilitate swallowing.
• Food is moved through the mouth, pharynx, and esophagus into the stomach during swallowing.
• Motor patterns with partial or total occlusion of the lumen move content in the anal direction and also provide a mixing function.

Importance of Patient History

• Three fundamental questions to ask when assessing a patient for dysphagia: Is dysphagia actually present, is it oropharyngeal or esophageal, and is it due to a structural abnormality or motor disorder?
• A thorough history can often identify the anatomical site and likely cause of dysphagia.
• The most valuable diagnostic test is collecting the patients history.

Globus vs. Odynophagia

• R/O Globus is a non-painful sensation of a lump, fullness, or tightness in the throat without impaired food bolus transport.
• Globus is most apparent between meals, not related to swallowing, usually alleviated by eating, and could be related to GERD.
• R/O odynophagia is pain on swallowing and is transient, only during swallowing.

Oropharyngeal Dysphagia Symptoms

• Cardinal symptoms include delayed or absent swallow initiation, nasal regurgitation, deglutitive cough (aspiration), and repetitive swallowing to clear the hypopharynx.
• Other supportive symptoms include bolus hold-up in the neck, dysphonia or garbled voice, and throat clearing.
• Bolus hold-up in the neck has low diagnostic specificity, with the actual hold-up being at or below the perceived level.
• Bolus hold-up in the retrosternal area indicates esophageal involvement.

Etiology of Oropharyngeal Dysphagia

• Neuromyogenic causes: Stroke/TBI, Parkinson's disease, ALS, multiple sclerosis, myasthenia gravis, myopathy (inflammatory, metabolic).
• Structural causes: Tumor, stenosis (postsurgical, radiation, idiopathic), Zenker’s Diverticulum, cricopharyngeal bar, esophageal web, extrinsic compression.

Oropharyngeal Dysphagia Management

• Identify correctable structural causes via endoscopy or radiography.
• Identify treatable systemic disorders like inflammatory, toxic, or metabolic myopathy, myasthenia gravis and Parkinson’s disease.
• Assessment of aspiration risk and the mechanics of oropharyngeal dysfunction via modified Barium swallow with speech language pathologist.

Esophageal Dysphagia Assessment

• Three key questions: solids only suggests structural issues, both solids and liquids suggest a motility disorder.
• Intermittent, non-progressive dysphagia, indicates an esophageal ring.
• Determine history of heartburn as it suggests reflux disease with peptic stricture.
• Other symptoms to look for: chest pain, regurgitation, weight loss, bleeding.

Temporal and Associated Factors of Esophageal Dysphagia

• Short history of progressive solid food dysphagia with weight loss suggests malignancy.
• Gradual onset of solid food dysphagia with heartburn suggests peptic stricture.
• Long history of intermittent, non-progressive solid food dysphagia suggests Schatzki's ring, or eosinophilic esophagitis.
• History of Raynaud’s phenomenon indicates Scleroderma.

Eosinophilic Esophagitis (EoE)

• EoE is a chronic disorder characterized by symptoms of esophageal dysfunction and esophageal inflammation with intraepithelial eosinophils.
• Patients typically have a history of asthma, atopy, or eczema.
• It presents with solid food dysphagia, which may be intermittent or progressive and untreated EoE can lead to strictures and perforation.
• Food impaction is common.

Eosinophilic Esophagitis (EoE) treatment:

• PPIs (Pantoprazole, Rabeprazole,Omeprazole, Esomeprazole)
• Topical steroids (Budesonide)
• Dupilumab (anti-IL4/IL13)
• Esophageal dilatation
• Exclusion diets – wheat, milk, soy, eggs, peanuts/treenuts, fish/shelfish

Investigation of Esophageal Dysphagia

• Endoscopy
• Barium swallow
• Esophageal manometry

Risk Factors for Esophageal Cancer

• Adenocarcinoma: Advancing age (>50), male gender, central obesity, tobacco use, Caucasian ethnicity, family history, long segment & circumferential Barrett's.
• Squamous Cell Carcinoma: Lower socioeconomic status, smoking, alcohol consumption, diet lacking fruits/vegetables, underlying conditions (achalasia, caustic stricture, radiation esophagitis), vitamin C deficiency, atrophic gastritis, HPV infection.

Esophageal Manometry

• High-resolution manometry (HRM) uses pressure topography.
• HRM catheters have multiple sensors spaced 1 cm apart to measure pressure along the length of the esophagus.
• Pressure data converts the tracing into a color-coded pressure topography, which is interpreted based on the Chicago classification v4.0.
• Sensors on the catheter measure changes in electric current and impedance, to measure bolus clearance.

Esophageal Motor Disorders

• Achalasia involves esophageal smooth muscles.
• Causes Aperistalsis and failure of LES relaxation due to defective innervation, with selective loss of inhibitory neurons in the myenteric plexus of the distal esophagus and LES.
• Affects all ages and sexes.
• Causes Dysphagia for solids and liquids +/- nocturnal regurgitation.
• Radiographic signs: "Bird's beak” at LES with incomplete opening, loss of primary peristalsis, and delayed esophageal emptying.
• Achalasia Treatment: Myotomy to release high pressure at LES (surgical or endoscopic POEM. Balloon dilation, Botox injections, Nitrates, and Nifedipine.

Diffuse Esophageal Spasm

• Disorder of esophageal smooth muscle with high-amplitude, premature (DL26, and surgery, and is associated with Atrophy of smooth muscle, aperistalsis, decreased LES pressure, GERD.
• Diffuse esophageal spasm presents with heart burn + dysphagia.
• This condition requires treatment for GERD, surgery should be avoided.