Anatomy & Physiology of Normal Deglutition

Flashcards about the Anatomy & Physiology of Normal Deglutition

Oral Cavity Structures

Lips, Teeth, Hard palate, Soft palate (velum), Mandible, Tongue

Oral Tongue

The part of the tongue you can see within the oral cavity.

Pharyngeal Tongue (Tongue Base)

Plays a big role in swallowing.

Faucial Arches

Palatoglossus & palatopharyngeus

Salivary Glands Function

Maintains oral moisture, reduces tooth decay, assists in digestion, and is a natural neutralizer of stomach acid.

Pharynx Walls

Posterior and lateral walls comprised of Superior, Medial, and Inferior pharyngeal constrictor muscles.

Cricopharyngeus

A component of the pharynx.

Larynx Function during Swallowing

Acts as a valve to protect the airway; true folds close first, then false folds; epiglottis retroflexes to cover the laryngeal vestibule.

Esophagus

Collapsed muscular tube approximately 23-25 cm long with a sphincter at each end (UES and LES).

Upper Esophageal Sphincter (UES)

A 2-4 cm zone of increased pressure at the top of the esophagus that opens to allow passage of the bolus and remains closed to keep air out.

Lower Esophageal Sphincter (LES)

Keeps food and secretions in the stomach and prevents backflow into the esophagus.

Average Number of Swallows per Day

Approximately 580, with the most during meals and fewest while sleeping.

Respiration and Swallowing

Respiration pauses during swallowing; the length of the pause depends on what and how much is being swallowed.

Oral Preparatory Phase

Food is manipulated in the mouth and masticated; labial seal maintained; open nasal airway; soft palate pulled down and forward.

Oral Transit Phase

Tongue propels food posteriorly until the bolus reaches the anterior faucial pillars; tongue acts as a ramp.

Pharyngeal Stage Trigger

Swallow reflex triggered by stimulation to the posterior tongue, faucial pillars, and/or upper pharynx; sensory information travels to the medulla via CN’s IX and X.

Pharyngeal Stage Motor Impulses

Elevation and retraction of the velum, tongue base retraction, elevation and closure of the larynx, retroflexion of the epiglottis, pharyngeal contractions, and opening of the UES.

Esophageal Phase

Movement of bolus from UES to LES via peristaltic wave; automatic, no volitional control; 8-20 seconds in duration.