tailieunhanh - Chapter 038. Dysphagia (Part 1)

Harrison's Internal Medicine Chapter 38. Dysphagia Dysphagia: Introduction Dysphagia is defined as a sensation of "sticking" or obstruction of the passage of food through the mouth, pharynx, or esophagus. However, it is often used as an umbrella term to include other symptoms related to swallowing difficulty. Aphagia signifies complete esophageal obstruction, which is usually due to bolus impaction and represents a medical emergency. Difficulty in initiating a swallow occurs in disorders of the voluntary phase of swallowing. However, once initiated, swallowing is completed normally. Odynophagia means painful swallowing. Frequently, odynophagia and dysphagia occur together. Globus pharyngeus is the sensation of. | Chapter 038. Dysphagia Part 1 Harrison s Internal Medicine Chapter 38. Dysphagia Dysphagia Introduction Dysphagia is defined as a sensation of sticking or obstruction of the passage of food through the mouth pharynx or esophagus. However it is often used as an umbrella term to include other symptoms related to swallowing difficulty. Aphagia signifies complete esophageal obstruction which is usually due to bolus impaction and represents a medical emergency. Difficulty in initiating a swallow occurs in disorders of the voluntary phase of swallowing. However once initiated swallowing is completed normally. Odynophagia means painful swallowing. Frequently odynophagia and dysphagia occur together. Globus pharyngeus is the sensation of a lump lodged in the throat. However no difficulty is encountered when swallowing is performed. Misdirection of food resulting in nasal regurgitation and laryngeal and pulmonary aspiration during swallowing is characteristic of oropharyngeal dysphagia. Phagophobia meaning fear of swallowing and refusal to swallow may occur in hysteria rabies tetanus and pharyngeal paralysis due to fear of aspiration. Painful inflammatory lesions that cause odynophagia may also cause refusal to swallow. Some patients may feel the food as it goes down the esophagus. This esophageal sensitivity is not associated with either food sticking or obstruction. Physiology of Swallowing The process of swallowing begins with a voluntary oral phase that includes a preparatory phase during which a food bolus suitable for swallowing is prepared and a transfer phase during which the bolus is pushed into the pharynx by contraction of the tongue. The bolus then activates oropharyngeal sensory receptors that initiate the deglutition reflex. The deglutition reflex is centrally mediated and involves a complex series of events. It serves both to propel food through the pharynx and the esophagus and to prevent its entry into the airway. When the bolus is propelled backward by the