Physiological Aspects of Normal Swallowing

Question 1

What are the 4 stages of normal swallowing?

Answer 1

1. Oral Preparation
2. Oral Transport
3. Pharyngeal
4. Esophageal

Question 2

Stage 1: Oral Preparatory Phase –> Function

Answer 2

Mastication, bolus formation, bolus maintenance

Question 3

Stage 1: Oral Preparatory Phase –> Aspects

Answer 3

Voluntary mastication and preparation of bolus

• voluntary control
• close lips —> good buccal tension
• velum lowered –> nasal breathing
• mastication –> lateral/rotary chewing + tongue elevation and pushes bolus posteriorly along hard palate

Question 4

Stage 2: Oral Transport Phase –> Function

Answer 4

Propel Bolus posteriorly

Question 5

Stage 2: Oral Transport Phase –> Aspects

Answer 5

• begins when tongue begins to propel bolus back
• tongue tip and sides to alveolar ridge
• velum elevates
• tongue base drops
• oral phase ends when bolus reaches ramus of mandible

Question 6

When is the pharyngeal phase triggered?

Answer 6

(Logemann 1998) sometime between the ant. faucial arches to the line of the ramus of the mandible

Question 7

Triggering the pharyngeal phase

Answer 7

• voluntary, rapid, no delay (1 - 1.5 sec)
• abnormal if oral transport has delay > 2 sec
• persons over 60 may have 0.3 sec longer

Question 8

What is the triggering point in adult patients?

Answer 8

anterior faucial pillar

Question 9

What is the triggering point for older adult patients?

Answer 9

middle of tongue base

Question 10

What is the triggering point for typical infant?

Answer 10

valleculae

Question 11

What nerves trigger the pharyngeal phase?

Answer 11

Cranial Nerve IX and X

Question 12

How is the pharyngeal phase triggered?

Answer 12

• sensory input from the oral cavity, tonsils, soft palate, and post pharyngeal wall
• posterior tongue movement

Question 13

Stage 3: Pharyngeal Phase –> Function

Answer 13

bolus moves inferiorly via a combo of gravity, base of tongue retraction, and pharyngeal wall constriction

Question 14

Stage 3: Pharyngeal Phase –> aspects

Answer 14

• involuntary
• lasts 1 sec or less
• velum elevates –> VP closure
• hyoid bone and larynx elevate and move anteriorly ( forward and upward)
• airway closure at 3 levels (breathing stops)
• tongue base contacts post. pharyngeal wall
• pharyngeal contraction
• upper esophageal sphincter (UES) opens

Question 15

At what 3 levels does airway closure occur during the pharyngeal phase?

Answer 15

• epiglottis
• aryepiglottic folds
• true VFs

Question 16

Stage 4: Esophageal Phase –> Function

Answer 16

the point where the bolus enters esophagus @ UES to point where bolus passes into stomach @ LES

Question 17

Stage 4: Esophageal Phase –> Aspects

Answer 17

• involuntary
• 8 to 20 sec in adults
• 3 to 10 sec in infants
• larynx descends to rest position & breathing resumes
• velum lowers
• UES contracts closes
• opening of the UES allows bolus to enter esophagus
• UES relaxes during swallowing
• elevation of larynx pulls UES open
• duration of opening inceases as bolus volume increases

Question 18

______ is produced by a series of localized reflexes in response to distension of wall by bolus; wave like muscular contraction.

Answer 18

Peristalsis

Question 19

After the food passes into stomach, ______ contracts/constricts.

Answer 19

LES

Question 20

Where does the esophagus join the stomach?

Answer 20

diaphragmatic or esophageal hiatus

Question 21

What are the 4 mechanisms of airway protection?**

Answer 21

1. hyoid/laryngeal elevation away from path of bolus
2. epiglottis retroflection
3. closure of laryngeal vestibule
4. adduction of false/true VFs

Question 22

What cranial nerve is in charge of the reflexive cough?

Answer 22

CN X (both motor and sensory)

Question 23

Reflexive cough results from what?

Answer 23

in response to material entering deep into laryngeal vestibule

Question 24

What cranial nerve(s) is charge of gag reflex?

Answer 24

Sensory CN IX and motor CN X

Question 25

Everyone has a gag reflex. T or F?

Answer 25

FALSE

many individuals w/ normal swallowing have an absent gag reflex

Question 26

What does the gag reflex have to do w/ swallowing?

Answer 26

Triggered by noxious stimuli and it is designed to squeeze material out of pharynx