swallowing (W10, 11 & 12) Flashcards
Mechanical processing
physical breakdown of food into smaller particles, mixes with secretions & move contents
Order – structures of gastrointestinal tract
Oral cavity
Pharynx
Esophagus
Duodenum of the small intestine
Jejunum of the small intense
Ileum of the small intense
Large intestine
Anus
function gastrointestinal tract
Oral cavity - form bolus through mastication
pharynx - passage to oesophagus
oesophagues - moves bolus to stomach
stomach - storage of ingested food
small intetines - absorbs carbs, amino acids
large intestine - absorbs water - propells feces
oral cavity
Opening where food is broken down from a large substance into a smaller substance that can be swallowed
oral cavity - mechanisms
activates muscles of mastication
elevates & deresses mandible
oral cavity - components
~ tongue = manipulates food between teeth
~ palate = rough surface helps tongue manipulate
~ H&S palate = work to keep food anteriorly to form bolus before swallowing
~ salivary glands = saliva
Esophagus
= muscular tube that moves bolus from pharynx to the stomach via peristalsis
Esophagus - components
Upper third – consists of strained muscles
Lower 2/3rds - consists of smooth muscles
Esophagus - function
- Moves bolus down the body
-Sits behind the trachea
- Has two end points that squeeze together (upper & lower esophageal sphincter)
Upper esophageal sphincter
regulates movement into esophagus
Lower esophageal sphincter
regulates movement into stomach
- Sphincters are normally tightly shut – because of the high muscle tone
- Help to prevent refluxes
- is innervated by the vagus nerve & sympathetic divisions of NS
Peristalsis
= A series of wave like muscle contractions that move the food through the digestive tract
Peristalsis - process
- Contraction of the esophagus sweeps the bolus along
- Bolus is propelled (seen in initial stage – 3rd stage)
- Alternating ways of contractions & relaxing
Stomach
= stores our ingested food
- Muscular wall allows for mechanical digestion
- Is smooth muscle – made up of mucosa & tissue
- Connects to the esophagus via the lower esophageal sphincter
Small intestines
absorbs carbs fats, proteins from food so they can be used by the body.
Small intestines - components
- Duodenum
(receives digestive secretions) - Jejunum
(chemical digestion & nutrient absorption) - Ileum
(moves food towards LI)
large intestine
absorbs water and vitamins, forms and propels fasces toward the rectum for elimination.
large intestine - components
- Cecum
A pouch that forms the first part of the large intestine - Colon
removes water & some nutrients from digested food
Pharynx role - airflow
(connected posteriorly to the nasal cavity where we breathe in & out)
Pharynx role - filtering
makes adjustments to our oral aparatus
Pharynx role - swallowing
transport of our bolus into our esophagus by squeezing it downwards
nasopharynx - function
- Respiration (passing & filtering air downwards)
- Protects body from airborne virsues via lymphatic tissue
- Resonance variation in speech
- stablize middle ear for hearing – clearing any built up mucous
oropharynx - function
- directs bolus in appropriate direction
- Palatine tonsils
- Accessory airways
Laryngopharynx - function
~ Upper boundary = the hyoid bone
~ Lower boundary = the cricoid cartilage
- Important for our inspired & expired air moving to the appropriate area
Epiglottic Valleculate
- Depression behind the root of the tongue between the epiglottis
- Saliva can pool here & is directed towards the piriform sinus
Pyriform sinus
recess on both sides of laryngeal orifice
Bolus passes into the left & right pyriform sulcus
Internal laryngeal nerve supplies sensation
CONSTRICTORS
Act in a squeezing motion
Ensure food is efficiently moved along the tract
Prevents the bolus from coming back up
Superior pharyngeal constrictors
upper part of the pharynx that constricts the upper part of the pharyngeal tube allowing us to get food from the mouth into the throat
Superior pharyngeal constrictors ACTIONS
~ decreases the cross section of the pharynx tube regionally
~ moves posterior pharyngeal wall forward
~ moves lateral walls inwards – squeezing them together
Middle pharyngeal constrictors
continues to contract, pushing the food further down the pharynx towards the esophagus
Uppermost fibers = cause obliquely upward movements
Lowermost fibers = run obliquely downward
Middle pharyngeal constrictors ACTIONS
~ decreases the cross section of the pharynx regionally
~ squeezes pharynx together bring the walls in
Inferior pharyngeal constrictors
performs a final squeeze, moving the food into the esophagus to travel down our gastrointestinal tract towards our stomach
Inferior pharyngeal constrictors ACTIONS
~ during contraction it draws the lower parts of the posterior walls forward and pull the lateral walls forward & inward
~ this creases the cross sectional area of the pharynx
~ closes our upper esophageal sphincter
Superior pharyngeal constrictors INNERVATION
pharyngeal branch of CNX (vagus nerve) & pharyngeal plexus
middle pharyngeal constrictors INNERVATION
pharyngeal branch of CNX (vagus nerve) & pharyngeal plexus
also branches of external nerves
inferior pharyngeal constrictors INNERVATION
pharyngeal branch of CNX (vagus nerve) & pharyngeal plexus
Palatopharyngeal
Pull lateral pharyngeal wall inward – reducing width of the pharynx
(raises pharynx)
Palatopharyngeal INNERVATION
pharyngeal branch of CNX (vagus nerve) & pharyngeal plexus
Salpingopharyngeus
Narrow muscles that originates near the lower border of the auditory tubes opening
Its fibers run downwards & insert into the lateral wall of the lower pharynx
This blends the fibers with the palatopharyngeal muscle
(Raises pharynx & opens auditory tube)
Salpingopharyngeus INNERVATION
pharyngeal branch of CNX (vagus nerve) & pharyngeal plexus
Stylopharyngeus
Pulls pharyngeal tube upwards & lifts the pharynx + larynx
Stylopharyngeus INNERVATION
glossopharyngeal nerves (CNIX)
Pharyngeal plexus
Innervated by motor fibers (CNIX & CNX)
vagus nerve - innervation
~ pharyngeal branch = (supplies mucosa for the levator veli palatini, superior and middle pharyngeal constrictors)
~ internal branch – Superior laryngeal = (nerve Supplies for the hypopharynx, epiglottis & subpharyngeal structures)
~ recurrent laryngeal branch Supplies = (subglottic larynx & inferior pharyngeal constrictor)
Gag reflex
body involuntarily attempts to eliminate unwanted objects from the oral cavity through muscle contraction at the base of the tongue and the pharyngeal wall
efferent / motor functions
CN IX & X (pharyngeal plexus)
Contraction of muscles of pharynx; soft palate & fauces
afferent / sensory functions
Glossopharyngeal CN IX
Stimulation of oropharynx
Phases of swallowing
Oral preparatory phase
Oral Transit phase
Pharyngeal phase
Oesophageal phase
Oral Preparatory Phase
- lasts for 3 seconds or longer
Oral Preparatory Phase process
open and depressed - Lip sealed (CNVII)
mandible elevated (CNV3)
Mastication of solids (CNV3) - grind & manipulate solid substance into a cohesive bolus
Anterior pulling of soft palate (CNX – palatoglossus muscle) to rest against the back of the tongue (CNXII) which is elevated serving to keep material in the oral cavity
Cheeks press in to limit the food in our buccal cavity
CNXII - Tongue sweeping to sweep up any crumbs in the buccal cavity
oral transit phase
Transport (a.k.a. oral propulsion phase or oral transit phase)
Lasts less than 1 second long
oral transit phase process
Bolus is transported back through oral cavity
Lip sealed – help keep the bolus over the tongue (CNVII)
Velum begins to elevate in preporation for the esophageal phase
The tongue – tip used to squeeze bolus against the hard palate (CNXII)
Tongue moves the bolus back towards the pharynx
(Propells the bolus)
cranial nerves & anatomical structures
lips sealed = CNVII
mandible lifts = CNV3
mastication = CNV3
soft palate pulls = CNX
Tongue elevates = CNXII
Tongue sweep = CNXII
oral cav sens =CNV2 + 3
pharyngeal phase
- velum moves the bolus by closing off the path to the nasal cavity & directing it toward the esophagus
Pharyngeal phase (Reflexive/involuntary)
~ Involuntary and is “triggered” once the bolus passes the anterior faucial pillars
~Rapid complex movements simultaneously to move bolus
Pharyngeal phase - key events
Velopharyngeal closure: Velum elevation and pharyngeal walls constriction (closure is forceful to prevent substances from passing through our nasal cavity)
Elevation of the hyoid bone: Elevates larynx fold over epiglottis (result of contracting the tognue)
Opening of the upper esophageal sphincter
Tongue root moves backward
movement of bolus
As bolus passes the anterior faucial arch pharynx is drawn upwards (to receive/ catch bolus)
Constriction of pharynx by sequential peristaltic (squeezing) action to cause downward movement of bolus towards oesophagus
Relaxation of the cricopharyngeal sphincter (or UES) to allow material to pass from pharynx into the oesophageus
oesophageal phase
Last between 8 to 20 seconds
Movement of bolus into the esophagus
oesophageal phase - process
Bolus is propelled through the esophagus by peristaltic actions of the esophageal walls.
Peristaltic contraction raises pressure behind the bolus and relaxation lowers pressure in front of the bolus, creating the pressure differential needed to propel it toward the stomach.
Relaxation of the lower esophageal sphincter to allow material to pass into the stomach.
variables effecting swallowing
- bolus
- body position
- development/aging
- sex
Dysphagia - swallowing
- An abnormality in the transfer of a bolus from the mouth to the stomach
- May involve one or more stages
- Impairment could be a delay/absence/misdirection of bolus transfer
- Transient, long term (chronic) or progressive
swallowing assessments
Video fluroscopy
= uses x-rays to image the movements associated with swallowing
Video fluroscopy process
- Substance mixed with barium sulfate
- consists of the swallowing of a series of liquid and solid substances (mixed with barium or accompanied by ingestion of a barium capsule to provide contrast)
- Provides the most comprehensive evaluation of swallowing
Dysphagia
Difficulty swallowing foods or liquids
(abnormality in bolus transfer)
Dysphagia causes
Neurogenic (e.g., stroke, PD, MND, Ageing)
Structural (e.g., glossectomy, cleft palate, frenulum)
Psychogenic
Classification of dysphagia
- Oropharyngeal dysphagia (moving bolus from the OC to the esophagus)
- Esophageal dysphagia
(passage of solid or liquid material through the esophagus) - Esophagogastric dysphagia
- Paraesophageal dysphagia
what bone forms most of the hard palate & upper teeth
maxillae / maxilla
what bone is mobile and contains the lower teeth
mandible (lower jaw)
what muscles are involved in smiling
zygomatic major + minor
sound production - movement & location of tongue
- tip of the tongue elevates/depresses
- it articulates with the alveolar ridge
swallowing - mechanisms that protect airways
soft palate = elevates to block nasal passage
epiglottis = tilts down to cover the opening of the larynx, to prevent food from entering the trachea
vocal cord = close tightly as an additional barrier
muscles involved in the velum (pharyngeal movement)
- palatine muscles
- TVP
- LVP
- palaglossus
- palatopharyngeus
muscles involved in the epiglottis (pharyngeal movement)
closes passively when larynx is elevated by suprahyoid muscles
muscles involved in the vocal cords (pharyngeal movement)
adducted by lateral cricoarytenoids
Velum/soft palate - airway protection
separates the oropharynx from the nasopharynx during swallowing to prevent food and liquids from moving into the nasal cavity
Epiglottis - airway protection
covers the larynx and trachea during swallowing to prevent food and liquids from entering the airway
Vocal folds - airway protection
adduct to protect the airway during swallowing
velum - dysfunction
- could cause nasal Regurgitation
- Inadequate closure can cause food or liquids to flow back into the nose, leading to discomfort and potential for aspiration
epiglottis - dysfunction
- food + liquid may enter the airway
- could cause problems with aspiration + choking
Vocal folds - dysfunction
- may lead to aspiration and choking
muscles of mastication
= muscles used for chewing + breaking down food
- Temporalis
- Masseter
- Lateral pterygoid
- medial pterygoid
muscles that depress the soft palate to stop food from moving into pharynx
Palatoglossus – palatine aponeurosis to side of tongue
Palatopharygeus – hard palate and palatine aponeurosis to lateral wall of pharynx