The Normal Swallowing Process:

1. Oral preparatory stage: The presence of food approaching the mouth is recognized, and the food is sensed in the mouth. The food is then mixed and chewed in the mouth, and its viscosity is reduced to an appropriate level in preparation for swallowing.

2. Oral stage: The tongue begins to move the food bolus backwards to the tongue root, preparing to initiate the swallowing reflex.

3. Pharyngeal stage: The swallowing reflex is triggered, and the food bolus is moved into the pharynx. At this point, the larynx is elevated, the soft palate covers the trachea, and the vocal cords close to protect the airway from food entering.

4. Esophageal stage: The food bolus is propelled by esophageal peristalsis and gradually enters the stomach.

In simple terms, dysphagia refers to the difficulty in moving food from the mouth to the stomach, including all the difficulties in behavior, sensation, and movement during the process of preparing to swallow. For example, when delicious food is in front of them, individuals with dysphagia may not be aware that they are about to eat, unable to recognize food, or have no physiological responses to food, such as increased saliva to facilitate chewing and swallowing. Severe or prolonged dysphagia can lead to malnutrition or aspiration pneumonia, which is life-threatening.

People of any age, from newborns to the elderly, may experience dysphagia, which may be caused by congenital abnormalities, central or peripheral nervous system damage, structural defects, radiation therapy to the head and neck, dementia, aging, or psychogenic problems, etc. It may occur suddenly, such as from a cerebrovascular accident, or gradually worsen over time, such as from some degenerative diseases, cognitive impairment, or malignant tumors.

Symptoms may include difficulty in recognizing food, placing food in the mouth, controlling food or saliva in the mouth, coughing before, during, or after swallowing, frequent coughing after meals, recurrent pneumonia, unexplained weight loss, wet, gurgling voice during speech, increased phlegm in the throat or chest after eating, and a feeling of difficulty in swallowing.

Complications of dysphagia may include pneumonia, malnutrition, or dehydration. Common evaluation methods include bedside or clinical examination, videofluoroscopic swallow study, and esophagogastroduodenoscopy.

Management of dysphagia may include non-oral feeding, such as nasogastric feeding or gastrostomy, or swallowing therapy. Nasogastric feeding involves placing a tube through the nose, pharynx, and esophagus into the stomach. Gastrostomy is a surgical procedure that involves making an opening in the abdomen under general anesthesia or local anesthesia and inserting a tube into the stomach. This method can address long-term severe swallowing problems because it eliminates the risk of nasal and pharyngeal stimulation from a nasogastric tube.

Swallowing therapy can be performed with oral or non-oral feeding and may involve postural adjustments, sensory stimulation, and exercise to improve swallowing function.