Dysphagia Health Article

Causes

Dysphagia occurs when any element of the normal swallow is disrupted. Oral structural abnormalities, muscular weakness, or incoordination may interfere with holding material in the mouth, forming it into a cohesive bolus, and propelling it backward into the pharynx. Lack of control over the material in the mouth might cause it to fall over the back of the tongue prematurely, while the airway is unprotected, or it might result in material remaining in the mouth after the swallow, when it could fall into the pharynx. If the bolus enters the pharynx before or after the swallow, while the airway is open and unprotected, there is a danger that aspiration will occur. Similarly, structural abnormalities, weakness, or incoordination in the pharynx or larynx may interfere with protection of the airway during the swallow or with the downward propulsion and emptying of the bolus into the esophagus. Finally, structural abnormalities, weakness, or incoordination in the esophagus may interfere with the progress of the bolus through the esophagus into the stomach.

Common etiologies of dysphagia include:

• strokes
• head injuries
• cervical spinal cord injuries
• progressive neurologic diseases
• head and neck cancer and the surgery or radiation used to treat it
• congenital syndromes and abnormalities
• esophageal stenosis
• esophageal tumors
• esophageal motility disorders
• achalasia
• gastroesophageal reflux disease

Medications may also cause or exacerbate dysphagia. Antipsychotic drugs that cause extrapyramidal symptoms like tardive dyskinesia may cause dysphagia, and some anticholinergic drugs may impair swallowing ability.

Symptoms

Common symptoms of dysphagia include:

• inability to control food or saliva in the mouth
• residue in the mouth after the swallow
• coughing during or after the swallow
• gurgly or wet vocal quality associated with swallowing
• unexplained weight loss
• increased time to consume a meal
• complaints of globus
• recurring pneumonia
• heartburn

Diagnosis

Diagnosis of dysphagia generally involves a clinical screening evaluation (sometimes called a bedside evaluation) and an instrumental evaluation. The clinical screening evaluation includes review of the medical history; current medical status; examination of oral anatomy and oral motor functioning; perceptual evaluation of laryngeal functioning; and observation of eating and drinking unless the risk of aspiration is very high and the individual is deemed too medically fragile to tolerate it. If the clinical screening evaluation suggests the presence of a dysphagia, it is usually followed by an instrumental evaluation.

The instrumental evaluation that is most widely used for diagnosing oropharyngeal dysphagia is the videofluoroscopic modified barium swallow (MBS) study. The MBS study allows the observation of structures and movements as the individual swallows controlled amounts of various consistencies (usually thin and thick liquid, a paste or pudding consistency, and solid food) while seated in an upright position. It provides information about transit times through the mouth and pharynx, motility problems, and the presence and etiology of aspiration. The MBS is done in the radiology department and requires the patient's cooperation. Thus, it may be contraindicated for patients who are unable to cooperate with instructions, or who are too medically fragile to be transported.

Videoendoscopy, or flexible fiberoptic examination of swallowing (FEES), is another procedure used to examine for oropharyngeal dysphagia. A flexible scope is inserted through the nose into the pharynx, allowing observation of the pharynx before and after the pharyngeal swallow is triggered. It does not allow observation of the oral or esophageal phases of the swallow, and, because the image is blocked by the constriction of the pharynx around the scope during the pharyngeal swallow, the presence and etiology of aspiration may be inferred but cannot be observed. This procedure can be done at the bedside and requires minimal cooperation from the patient, making it useful for patients who cannot tolerate an MBS study.