Physiological Aspects of Normal Swallowing Flashcards
What are the 4 stages of normal swallowing?
- Oral Preparation
- Oral Transport
- Pharyngeal
- Esophageal
Stage 1: Oral Preparatory Phase –> Function
Mastication, bolus formation, bolus maintenance
Stage 1: Oral Preparatory Phase –> Aspects
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
Stage 2: Oral Transport Phase –> Function
Propel Bolus posteriorly
Stage 2: Oral Transport Phase –> Aspects
- 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
When is the pharyngeal phase triggered?
(Logemann 1998) sometime between the ant. faucial arches to the line of the ramus of the mandible
Triggering the pharyngeal phase
- 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
What is the triggering point in adult patients?
anterior faucial pillar
What is the triggering point for older adult patients?
middle of tongue base
What is the triggering point for typical infant?
valleculae
What nerves trigger the pharyngeal phase?
Cranial Nerve IX and X
How is the pharyngeal phase triggered?
- sensory input from the oral cavity, tonsils, soft palate, and post pharyngeal wall
- posterior tongue movement
Stage 3: Pharyngeal Phase –> Function
bolus moves inferiorly via a combo of gravity, base of tongue retraction, and pharyngeal wall constriction
Stage 3: Pharyngeal Phase –> aspects
- 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
At what 3 levels does airway closure occur during the pharyngeal phase?
- epiglottis
- aryepiglottic folds
- true VFs
Stage 4: Esophageal Phase –> Function
the point where the bolus enters esophagus @ UES to point where bolus passes into stomach @ LES
Stage 4: Esophageal Phase –> Aspects
- 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
______ is produced by a series of localized reflexes in response to distension of wall by bolus; wave like muscular contraction.
Peristalsis
After the food passes into stomach, ______ contracts/constricts.
LES
Where does the esophagus join the stomach?
diaphragmatic or esophageal hiatus
What are the 4 mechanisms of airway protection?**
- hyoid/laryngeal elevation away from path of bolus
- epiglottis retroflection
- closure of laryngeal vestibule
- adduction of false/true VFs
What cranial nerve is in charge of the reflexive cough?
CN X (both motor and sensory)
Reflexive cough results from what?
in response to material entering deep into laryngeal vestibule
What cranial nerve(s) is charge of gag reflex?
Sensory CN IX and motor CN X
Everyone has a gag reflex. T or F?
FALSE
many individuals w/ normal swallowing have an absent gag reflex
What does the gag reflex have to do w/ swallowing?
Triggered by noxious stimuli and it is designed to squeeze material out of pharynx
