Week 1 Flashcards
What are the stages of a swallow?
Oral preparatory stage (chewing)
Oral stage (propulsion of bolus)
Pharyngeal stage (pharyngeal swallow)
Esophageal stage (esophageal transit)
The swallow is not _____
segmental, what takes place in one phase will affect the others
What are the two binary goals?
Seal the airway
Move food through to the esophagus
What are major events in the oral prep phase?
Sealing oral cavity (close lips, posterior tongue to velum)
Mastication of bolus (if needed)
Mixing bolus with saliva (starts digestion)
Dividing bolus into pieces for transport to pharynx (piecemeal deglutition)
What nerves and muscles are used in the oral prep phase?
Obicularis oris (CN VII) - lip opening and closing, lip seal
Buccinator (CN VII) - contracts to keep bolus on teeth/prevent pocketing in cheeks
Tongue sensation (taste and touch, CN V, VII, IX) - to determine taste, size, texture and location of bolus
Tongue muscles - alter shape and tone of tongue during oral prep to move bolus (CN XII) AND elevate posterior tongue to seal with velum (contraction of palatoglossus, CN X)
Muscles of mastication (CN X) - contract and relax to facilitate chewing. Break down bolus and mix with saliva
Salivation (CN VII, IX) - lubricate and early digestion of bolus (mandibular sinus)
Why is saliva very important?
Maintains healthy oral tissue
Prevents tooth decay
How much saliva does an average healthy person produce daily?
1-1.5 Liters
What is not a sign of impairment in the oral prep phase?
Oral seal not being constant during mastication
Chewed bolus collecting in vallecula as other food is being chewed
What are major events in the oral phase?
Bolus is propelled from oral cavity to pharynx
Soft palate elevation
Voluntary opening of the pharynx (velum lifts with posterior tongue depresses)
Early hyoid elevation (in anticipation of pharyngeal phase)
What nerves and muscles are used in the oral phase?
Superior longitudinal muscle (CN XII) - tongue tip elevation to alveolar ridge
Levator veli palatini (CN X) - elevation of velum
Hyoglossus & styloglossus (CN XII) - posterior tongue depression
Anterior tongue (CN XII) - compression against hard palate in anterior to posterior wave to move bolus along dorsum of tongue
Obicularis oris & buccinator (CN VII) - contract to present pressure escape at lips )
Superior pharyngeal constrictor (CN X) - contracts to close around elevated velum (protection against nasal regurgitation)
Mylohyoid (CN V) - moderate hyoid elevation in prep of pharyngeal phase
Swallowing occurs during _____
apnea or cessation of breathing
You should not ______ after swallow
inhale
What are the normal swallowing patterns
Exhale > Apnea/Swallow > Exhale ~ 80%
Inhale > Apnea/Swallow > Exhale ~ 20%
What are the characteristics of the pharyngeal phase?
COMPLEX - Pharynx goes from default breathing fashion to secondary swallowing fashion
FAST/EFFICIENT - Apnea can’t last long so swallow must be fast. < 1 sec in healthy swallows
EXCITATORY and INHIBITORY - Involves both activation and inhibition of muscles in a coordinated fashion
INVOLUNTARY - Can not stop or reverse event
What are major events in the pharyngeal phase?
Jaw stabilization
Bolus transfer to pharynx
Hyo-laryngeal elevation
Laryngeal vestibule closure (epiglottis to arytenoids)
True and false VF closure
Pharyngeal shortening and constriction
Upper esophageal sphincter opening
Which major pharyngeal phase events protect the airway?
Hyolaryngeal excursion
Epiglottis to arytenoid
True and false VF closure (bottom-up (true first then false))
Which major pharyngeal phase events move bolus through esophagus?
Hyolaryngeal excursion Base of tongue propulsion Pharyngeal constriction and shortening Gravity Cricopharyngeal relaxation Negative suction
What nerves and muscles are used in the pharyngeal phase?
Muscles of mastication (CN V) - stabilize jaw and tongue muscles
Tongue muscles (CN XII) - propel bolus posteriorly, tongue base retraction
Superior, middle and inferior pharyngeal constrictors (CN X) - propel bolus through sequential pharyngeal constrictors (peristalsis)
Palatopharyngeus (CN X), salpingopharyngeus (X), stylopharyngeus (IX) - shorten the pharynx to decrease distance for bolus travel
Suprahyoid muscles - pull hyoid and larynx superior and anteriorly (mainly mylohyoid (CN V) for superior movement/anterior movement mainly by geniohyoid (C1))
Laryngeal muscles (CN X) - activate laryngeal adductors
Cricopharyngeus (CN X) - tonic contraction to keep UES closed
What contributes to SAFETY of the swallow?
Airway protection:
Hyolaryngeal excursion
True VF closure
False VF closure
Epiglottis to arytenoid seal
What contributes to EFFICIENCY of the swallow?
UES opening (aka PES opening)
Tongue propulsion Pharyngeal contraction and shortening Hyolaryngeal traction forces Gravity Cricopharyngeal relaxation Negative pressure
What are major events in the esophageal phase?
Bolus is transported down esophagus to stomach
The lower esophageal sphincter (LES) relaxes and bolus moves into stomach
What is the longest phase of swallowing?
Esophageal (8-20 seconds)
What nerves or muscles are used in the esophageal phase?
Esophageal muscle (CN X) - peristaltic wave of contraction to pusch bolus to LES which relaxes to move bolus to stomach
First ____ of esophagus is made of and controlled by?
Last _____ are made of and controlled by?
First 1/3 is striated muscle - controlled by nucleus ambiguus
Last 2/3 is smooth muscle and controls by ANS
What are causes of dysphagia?
Neurological Structural (tumor, surgical, edema) Head and neck cancer Aging Other (meds, psychogenic, respiratory compromise)
Penetration
Bolus in laryngeal vestibule ABOVE VF
Aspiration
Bolus BELOW VF
What is the response to Penetration?
Swallow
if no swallow, likely will lead to aspiration
What is the response to Aspiration?
Cough
if not cough, silent aspiration
What are two common places of bolus collection?
Vallecula
Pyriform sinus
What may happen if a pt has no safety issues, just efficiency issues?
Weight loss
Social aspect/different diet
QOL implications
