Section 12 Flashcards
What are the laryngeal joints? Discuss their motion and function.
Cricothyroid joint = attaches between the cricoid and thyroid cartilages. Specifically, attached at inferior horns at lateral surface of cricoid cartilage.
- Motion: rocking up & back (sometimes sliding)
- Function: role in adjusting human voice pitch by changing tension of vocal cords
- Cricoarytenoid joint = attachment at bottom of arytenoids and top of cricoid cartilage. Described like a signet ring.
- Motion: primarily rocking and arytenoids moving up & back, sometimes sliding.
- Function: associated with abduction and adduction of VF
What muscles are involved in the oral preparatory phase of swallowing?
Buccinator (CNVII) - counter force the tongue to facilitate bolus control
Orbicularis oris (CN VII): closing lips, resists distention when blowing
Masseter (CN V): elevates mandible
Temporalis (CN V): elevates and retracts mandible
Medial pterygoid (CN V): closes jaw by raising mandible against maxilla
Lateral pterygoid (CN V): assists in opening mouth by drawing condole and articular disk forward.
What is the role of the tongue in swallowing?
Anterior tongue: formation, placement, and manipulation of the bolus in the oral cavity
Posterior tongue: containment in the oral cavity and propulsion into the pharynx.
What muscles are involved in the oral phase of swallowing?
Levator veli palatini (CN X): raises soft palate and close off nasal cavity.
Hyoglossus & styloglossus (CN XII) = posterior tongue depression
Superior pharyngeal constrictor (CN X via pharyngeal plexus): Forceful closure of the nasopharynx and constriction of the pharynx
Mylohyoid (CN V) = hyoid bone elevation
Stylohyoid = draws hyoid back and elevates tongue
Geniohyoid (CN XII, C1-2) = hyoid bone elevation
What are the key muscles to the pharyngeal phase?
Lateral cricoarytenoid (CN X): adducts vocal folds
Transverse arytenoid (CN X): adducts vocal folds
Thyroarytenoid (CN X): help to close off airway by narrowing laryngeal inlect
Salpingopharyngeus = elevates pharynx (CN X)
Stylopharyngeus = elevates pharynx (CN IX)
(Palatopharyngeus - CN X) = elevation of the pharynx
Thyrohyoid (CN XII, C1) = depresses hyoid and elevates the larynx. This elevation of the larynx causes a reduction in pressure in UES, allowing it to relax and open more easily.
This elevation also aids with epiglottic inversion
Cricopharyngeus (CN IX, X) = contracted at rest to prevent reflux; relaxes during the swallow to allow the bolus to pass from pharynx into esophagus. Creates the upper esophageal sphincter.
3 sets of semi-circular muscles:
Superior constrictor = constricts pharynx to push bolus down (CN X)
Middle constrictor = constricts pharynx to push bolus down (CN X)
Inferior constrictor = constricts pharynx to push bolus down (CN X)
What are we looking for in a typical swallow?
Safety and efficiency
Describe the oral phase of the swallow.
Food is manipulated and masticated voluntarily prepped for transport.
Food it put into oral cavity, and sensory components are taste, temperature, and pressure of the bolus on tongue → need a labial seal to reduce spillage lower velum
Rising of posterior tongue to articulate with velum to create a seal
Mastication of material with rotary jaw movement
Increased tongue to palate contact, and bolus moves posteriorly
Saliva is mixed with food from 3 glands that make 2 types of saliva
Describe the oral phase of swallowing.
Voluntary phase where tongue propels food posteriorly until swallow is triggered
Lower posterior tongue
Velum raises to close off nasal cavity
Tongue holds the bolus up against the hard palate
Bolus is propelled by the anterior tongue moving posteriorly (at alveolar ridge) until it hits the faucial pillars
Describe the pharyngeal phase of swallowing.
Swallowing reflex once hits faucial pillars carrying bolus through pharynx
Bolus hits anterior faucial pillars
Pharyngeal muscles contract to raise the pharynx
The airway is protected in 4 ways (laryngeal elevation, epiglottic deflection, hyolaryngeal excursion, adduction of vf)
Tongue base retracts to contact the posterior pharyngeal wall
Pharyngeal constrictors activated in a rostral caudal direction for peristalsis
(superior, middle, then inferior constrictor). Also longitudinal muscles shorten and widen pharynx (stylopharyngeus, palatopharyngeus, salpingopharyngeus)
UES opening (intrabolus pressure, build up of positive pressure in pharynx,
relaxation of cricopharyngeus) **can get stuck in vallecula or pyriform sinuses
Describe the esophageal phase of swallowing.
Starts once bolus passes through UES, involves relaxation of cricopharyngeus, then returns to contracted state to avoid reflux
Esophageal peristalsis, propelling bolus towards lower esophageal sphincter (healthy transit time around 8-13 seconds)
LES relaxes and bolus squeezed into the stomach
Several waves occur up to an hour after swallow to clear esophageal residue
What are the four methods of airway protection?
Vocal fold adduction (true & false) to cease respiration & seal airway prevent aspiration
Epiglottic deflection (tip epiglottis to arytenoids)
Elevation of larynx through bunching up of aryepiglottic folds
Anterior hyolaryngeal excursion, brings larynx with it and tongue base
Describe the normal actions of UES opening.
Intrabolus pressure from tongue and pharyngeal muscles
Buildup of positive pressure in pharynx and negative pressure in esophagus (moves from higher pressure to lower pressure area)
Cricoid elevation (larynx elevates, thyroid cartilage and cricoid elevated, pulling on UES to loosen)
What is IDDSI?
This framework outlines specific food characteristics of food for that level, rationale for that level, recommended testing methods to make sure food fits the criteria.
How do you know which level to choose on IDDSI?
Flow test for liquid flow: Amount of fluid remaining in the 10 ml syringe after 10 seconds. Confirm level 3&4 with fork drip test:
○ Level 4 sits in a mound above form, 3 drips slowly or in dollops through prongs
Fork pressure test for levels 5-6:
○ Fork can be applied to food. Apply amount of pressure needed to blanch a thumbnail white ( 17 kilopascals) - that is the pressure used to generate swallow reflex. Comes from review of choking literature, size of airway, endotracheal tubes
○ When fork is lifted, should be squashed and not splintered, and should not return to original shape. Can also do chopstick test or finger test for other cultures
Describe the penetration aspiration scale’s scores.
1 - none - no entry of material
2 - penetration - entry into larynx with clearing
3 - penetration - entry into larynx without clearing
4 - penetration - material contacts the true vocal folds with clearing
5 - penetration - material contacts true vocal folds without clearing
6 - aspiration - material enteres trachea and is spontaneously cleared into larynx or pharynx
7 - aspiration - materials enter trachea and is not cleared following attempts
8 - asporation - material enters trachea with no attempt to clear.
Describe the eisenhuber scale for residue rating.
0 = none (severity), 0% or coating (amount/% fill) 1 = mild, <25% 2 = moderate, >25% and <50% 3 = severe, >50%
What are some populations that are at risk for dysphagia?
Surgery, radiation, and chemotherapy
Neurodisorders: ABI, ALS, Muscular dystrophy, MS, myasthenia gravis, Dementia
Developmental disorders: CP, any disorders with low muscle tone (ex. down’s syndrome), craniofacial disorders
How can dementia cause dysphagia?
Physical: inability to recognize food or drinks, inability to gauge food temp, reduced awareness of hunger & thirst, changes in smell & taste, vision probs
Sensory: inability to recognize, gauge food temperature, reduced awareness of hunger and thirst, changes in sensation, vision problems.
Environment: too loud, too much visual stimulation, poor lighting, unpleasant odors, or uncomfortable room temp.
Poor oral hygiene: causes painful eating due to dry mouth, gum disease, ulcers, poor dentition
Medication
Communication and cognitive problems: inability to express news and food preferences, difficulty following instructions, difficulty remember to eat, increased conduction leading to unwanted meal behaviours
What are some aspects of the different types of dysarthria that could lead to dysphagia?
Ataxis: uncoordinated jaw, face, and tongue, head tremor.
Hypokinetic: tremulous jaw, lips, and tongue, reduced range of motion on AMR tasks, resting tremor, rigidity.
Hyper: involuntary head, neck, and laryngeal movements, deviation of head position, multiple motor tics, myoclonus, tremors, facial grimacing.
Spastic: pathologic oral reflexes (sucking, snout, jaw jerk), hypertonia, hyperactive gag reflex.
Flaccid: weakness, facility, atrophy, fasciculations, hypoactive gag, unwanted contractions, nasal back flow while swallowing.
UMN: unilateral lower face weakness and lingual weakness (no atrophy/fasciculations), nonverbal oral apraxia
Describe the interrelationship between the CNS in the swallowing centre of the brain.
Swallowing centre: medulla oblongata.
Pharyngeal swallow is mainly in the PNS, with both efferent (motor) information from the CNS to muscles, and afferent (sensory) information to the CNS.
The role of the medulla oblongata is that the patterned sensory information comes in à medulla oblongata (swallowing centre) → stereotyped motor output.
What happens is there’s AFFERENT sensory info that comes in, mostly by cranial nerves 9 & 10 from the muscles à Comes into medulla oblongata (nucleus tractus solitarius specifically), which then passes it on to the nucleus ambiguous, which is EFFERENT, and sends the motor signal that is fed back down to the muscle, which is the pharyngeal swallow reflex.
What does a positive result from a swallowing screening indicated and when should you screen?
Positive result: indicated risk for a swallowing problem and the need for a complete assessment.
When: when someone enters a hospital or clinic and does not yet have a swallowing/feeding diagnosis.
What are some important aspects of medical history to gather when assessing swallowing?
Respiratory status: pneumonia? tracheostomy? mechanical ventilation?
Neutritional and gastro-intestional status: oral vs. non-oral nutrition, presence of NG or PEG tube.
Cardiac status: may be associated with tachypnea (increased work to breath) which can make swallowing coordination more difficult.
Dentition
Structural problems
Cancer or tumours: treatment can cause side-effects with swallowing issues
Psychiatric history: medications
Prior surgeries
Medical status: QoL, comorbid conditions.
What are some cognitive abilities important to a swallowing screening/assessment?
Client’s general awareness
Ability to follow directions
Ability to ask and/or answer questions
Overall conditioning
What are some considerations when assessing a child’s swallowing?
Feeding context: location where child is usually fed, positioning equipment used to assist, etc.
Feeding method: how the child is fed, mealtime routines, if they are fed asleep.
Anthropometric measurements: understand child’s growth by looking at weigh, height/length, and other relevant measurements.
Caregiver-child feeding interactions: ability of caregiver to respond to cues from the child, pave of feeding, and ability to recognize when child is full. `
How could you screen for dysphagia?
Swallowing task (3-ounce water swallow test): required to drink 9 ounces of water with no interruption. Further testing if unable to complete task, coughing, or choking, wet/hoarse voice quality (within 1-minute of completing) - does have a risk of false negative Other: Perry Standardized swallowing assessment, Daniel's test, Eating assessment tool (EAT-10),
What is the purpose of a cranial nerve exam?
Gain information about patient’s ability to perform certain motor tasks
Provides details about a patient’s: strength, symmetry, range of motion, coordination, and presence/absence of reflexes
Caveat: Some structures can perform poorly for one task (i.e. swallowing), but well for another (i.e. speech). Depending on the
location of neural damage, one or more functions could be impacted for the same structure.
OVERALL: Observing any non-swallowing movement in a clinical exam does NOT confirm adequate swallowing movement
How do you test the function of CN V?
Motor Function: Movement of the jaw, hyoid and palate.
Sensory function: Anterior 2/3rds tongue + palate + face.
Testing:
1. Ask the patient to close their eyes and touch their nose with a Q-tip. If they can feel it, the sensory function of CN 5 is intact.
2. Open jaw as wide as possible → see if it deviated to one side.
3. Ask the patient to close mouth, have SLP pull down on jaw.
4. Ask the patient to keep mouth open, have SLP push up on chin.
5. Move the lower jaw from side to side. Problems with jaw movement may indicate problems with CN5
motor function.
6. Ask patient to clench teeth → check temporalis and masseter muscles
