Pediatric emergency medicine trisk 1090 1090
Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (101.39 KB, 1 trang )
To facilitate suckle feeding and breathing, the infant oropharynx is
anatomically different from the adult, with a relatively larger tongue, smaller oral
cavity, and more anterior and superior epiglottis and larynx. As the face and
mandible grow, the oropharynx enlarges, creating more room for the eventual
voluntary use of the tongue and dentition, and the larynx descends, eventually
allowing for mouth breathing. Although breathing continues to cease during
swallows, the older child depends less on close coordination between eating and
breathing.
A normal swallow, using the suckling infant as an example, begins with
rhythmic movement of the lips, tongue, and mandible. These parts function as a
unit, creating negative intraoral pressure, while also compressing the nipple. The
milk expressed from each suckle is stored in the posterior oral cavity until a larger
fluid bolus is formed. As the tongue delivers the bolus to the pharynx, the
nasopharynx is closed off by the posterior tongue and by elevation of the soft
palate. The larynx elevates to a position under the tongue, closing the airway, as
the epiglottis inclines to direct the bolus posterior. A pharyngeal wave of
contraction sweeps the bolus toward the upper esophagus, where the
cricopharyngeal sphincter relaxes, allowing passage into the esophagus. As the
esophagus begins peristaltic contractions and the bolus moves past a relaxed
lower esophageal sphincter into the stomach, the airway reopens, the
cricopharyngeal sphincter constricts to close the upper esophagus, and
respirations resume. Dysphagia can result from disruption of normal mechanisms
at any stage of the swallowing process.
DIFFERENTIAL DIAGNOSIS
Acute dysphagia is an urgent symptom needing immediate evaluation. While this
may be an acute symptom in a healthy child, it may be a new or recurrent
symptom in the increasing number of children surviving with chronic conditions.
The incidence and prevalence of pediatric dysphagia is increasing, probably due
to improved early medical and supportive care for prematurity and other
conditions. The differential diagnosis for dysphagia is extensive and is commonly
divided into pre-esophageal or esophageal disorders ( Table 56.1 ). Preesophageal causes of dysphagia are further subdivided into anatomic categories,
including nasopharyngeal, oropharyngeal, laryngeal, and generalized problems.
Infectious and inflammatory disorders of either anatomic region may disrupt
swallowing, whereas neuromuscular problems tend to be predominantly preesophageal, given the autonomic function of the esophagus. However, the
esophagus can be affected by motility disorders intrinsic to smooth muscle.
