CHAPTER 56 ■ PAIN: DYSPHAGIA RAHUL KAILA, RONALD A FURNIVAL, GEORGE A (TONY) WOODWARD INTRODUCTION The primary function of swallowing is the ingestion, preparation, and transport of nutrients to the digestive tract Secondary functions of swallowing are the control of secretions, clearance of respiratory contaminants, protection of the upper airway, and equalization of pressure across the tympanic membrane through the eustachian tube Dysphagia is defined as any difficulty or abnormality of swallowing Dysphagia is not a specific disease entity but is a symptom of other, often clinically occult, conditions and may be life-threatening if respiration or nutrition is compromised Odynophagia (pain on swallowing) or sialorrhea (drooling) may also be present in the dysphagic pediatric patient Globus pharyngeus refers to the feeling of a lump in the throat This chapter briefly presents the normal anatomy and physiology of swallowing, the differential diagnosis of disturbances of this process, and the evaluation and treatment of the pediatric patient with dysphagia PATHOPHYSIOLOGY Swallowing begins in utero as early as the 10th to 14th week of gestation, playing an important role in gastrointestinal development and regulation of amniotic fluid volume By the 34th week of gestation, this complex process, involving 26 muscles, cranial nerves (V, VII, IX, X, XI, and XII), and cervical nerves C1 to C3, is functional, although incompletely coordinated with breathing In the first few days after birth, each infant develops an individual pattern of sucking, swallowing, and breathing, usually with a 1:1 or 1:2 ratio of breaths per suckle, to prevent aspiration of material into the larynx This stage of suckling, or suckle feeding, is primarily under medullary control, with minimal input from the cerebral cortex A transitional period begins at months of age, as the cortex gradually exerts more control over the pre-esophageal phase of swallowing, allowing for the introduction of solid foods Swallowing in the esophageal region remains an autonomic process, with vagal sensorimotor control coordinating peristalsis of the upper striated and lower smooth muscle of the esophagus By years of age, the swallowing pattern is mature, although the pediatric patient, unlike the adult, may regress to a less mature stage if normal swallowing is disrupted