swallowing :) Flashcards
what is deglutition
action of preparing food within oral cavity and transmitting the bolus from OC through pharynx and oesphagus
phases of swallowing
oral phase
pharyngeal phase
oesophageal phase
what are the phases e.g. oral is …
oral - voluntary
others - reflexes i.e. cannot be stopped
Oral preparatory phase
preparation of food by mastication, mixing with saliva
how is the consistency of food monitors by
sensory receptors in the oral mucosa so no choking occurs
oral transit phase
oral cavity occluded by raising the tongue to the palate from front to back
back of tongue lowered
backwards movement pushes food down oesophagus
extrinsic muscles of the tongue
palatoglossus
genioglossus
styloglossus
hyloglossus
palatoglossus
one of the arches in the mouth
muscle of the palate and tongue
genioglossus and styloglossus functon
used to form a Shute to propel food back
trigger points in the mouth
palatoglossal arch
soft palate
posterior wall of pharynx
palatine tonsil?
contact with trigger point leads to
reflex pharyngeal contraction
reflex actions to protect lower airway
what must happen for oral phase to complete
mouth closed
- uses jaw elevation branch V3
- lip muscles of facial expression (CNVII)
what happens when the mouth is closed (muscles)
fixes the hyoid bone and suprahypid muscles to allow raining of larynx and pharunx
transit phase
elevation of soft palate to stop food entering the nasopharynx and nose
suspension of respiration to minimse inhalation of food into larynx
muscles of soft palate
palatoglossus
palatopharyngeus
levator veli palatini
tensor veli palatini
palatoglossal
muscle of palate and tongue
anterior arch in oral cavity
palatopharyngeal
posterior arch in oral cavity
what do the arches in the OC do
depress the soft paalte
levator veli palatini/tensor veli palatini
elevatee soft palate to close off nasopharynx
nerve supply to muscles of palate
vagus
except tensor veil palatine - trigeminla V3 branch
actions of the pharyxn
passage of food through pharynx
protection of lower airway to prevent food inhalation
how is the lower airway protected
suspension of respiration
elevation of larynx ny suprahyoid muscles (fix hyoid bone so larynx can elevate)
narrowing of laryngeal entrance
strong adduction of vocal folds
laryngeal elevation process
opens pharynx
pulls larynx under tongue
epiglottis flaps over laryngeal entrance
epiglottis
elastic cartilage
protects laryngeal entrance
convex laterally
where is food directed around epiglottis
from laryngeal entrance into pyriform recesses (food may get trapped)
what innervates the area around pyriform recesses
internal laryngeal nerve (branch off superior larynegela nerve, off vagus)
muscles which narrow laryngeal entranec
aryepiglottic muscles
which muscles adduct the vocal folds
interarytenoids
laterla cricoarytenoids
what is closed to prevent anything passing further into larynx
rima glottis
how is a cough reflex initiatied
noxious stimulation of pharynx larynx or bronchial passagay
procedure of cough reflec
diaphragm and IC muscles contract
rima glottis close and VF adduction
expiratory muscle contraction
bronchi and non cartilage’s portions of trachea collapse
when does the gag reflex occur
if swallowing reflex is elicited but the material cannot be swallowed
what happens during gag reflex
mouth open
posterior part of tongue elevated to expel material
soft palate elvated to stop entering nasopharynx
sensory nerves involved in swallowing
5 - trigeminal (mouth and lips)
9 glossopharyngeal (pharynx initiates swallowing reflex)
vagus (pharynx)
motor nerves involved in swallowing
5 tirgeminla V3 - muscles of mastication and suprahyoids
facil 7 - muscles of facil expression and suprahyoids
vagus - muscles of soft palate, pharynx and larynx
12 hypoglossal - muscles of tongue
causes of dysphagia
space occupying lesions e.g. cancer
- occlusion by enlargement of adjacent structure
neurogenic
- neuromuscular disease
- damage to CN
- damage to control centres of swallowing
- xerostomia
how is swallowing controlled
swallowing centres I the brain stem
higher centres in insular cortex
problems caused by dysphagi
malnutitirion
socail problems
aspiration
what is silent aspiration
inhalation of food without cough reflex
process of silent aspiration
food enters bronchial tree and stagnates
may become infected
pneumonia and death
what nerve elicits the coutgh reflex
superior laryngeal nerve (CN X)
effects of neurogenic dysagia
swallowing slow
phases may be uncoupled
assessment of swallowing
sips of water
soft piece of cake
video fluroscopy
nasoendoscopy
