Introduction to Swallowing and Dysphagia Flashcards
When can human fetus swallow?
12 weeks before CNS has developed
2 functions of swallowing?
- Nutrition
- Protection from aspiration
On average human swallow ___
500 x/day
What are the 5 cranial nerves involved in swallowing? (TFG-VH)
Trigeminal Facial Glossopharyngeal Vagus Hypoglossal
Which nerves are involved in oral prep and transit phase?
Trigeminal and Facial
Motor and sensory function of trigeminal nerve?
Mastication, taste and touch
Sensory function of facial nerve?
Taste on anterior 2/3 of tongue
Which nerves are involved in the pharyngeal and esophageal phases?
Glossopharyngeal and Vagus
What motor and sensory functions is the glossopharyngeal nerve responsible for?
Swallowing, gag reflux and palatal/oral sensations
What motor and sensory functions is the vagus nerve responsible for?
GI, cough and taste on posterior 2/3 of tongue
Facial nerve responsible for taste on posterior/anterior of tongue
Anterior
Vagus nerve responsible for taste on posterior/anterior of tongue
posterior
What phase is the hypoglossal nerve responsible for? What does it do?
All phases
Tongue movement
4 phases of swallowing? (OOPE)
- Oral preparatory
- Oral transit
- Pharyngeal
- Esophageal
Explain the oral preparatory phase
Voluntary phase which involved the trigeminal, facial and hypoglossal nerves. Lips will seal, and soft palate drops down over base of tongue the prevent food spillage within the airway. Saliva is secreted, mastication and bolus is formed.
What does mastication do?
-Break down of food, mixing with saliva, stimulates taste
Largest muscle involved in mastication?
Tongue (controlled by hypoglossal nerved)
Explain the oral transit phase
Under voluntary control, using the trigeminal, facila and hypoglossal nerves. The soft palate will seal the nasal cavity, while the posterior tongue depresses, allowing for the propelling of the bolus to the oropharynx. Meanwhile, the anterior of the tongue will be elevated and pressed against the hard palate and will contract in a wave like motion to propel the bolus into the oropharynx.
What are some consideration in the oral transit phase?
Foods that don’t form cohesive bolus may get stuck
Which phase is the epiglottis open?
Oral transit phase
Explain the pharyngeal phase
Under autonomic control by the glossopharyngeal, vagus and hypoglossal nerves. The soft palate will continue to seal the nasocavity, while laryngeal muscles close off vocal cords and epiglottis covers the larynx. The bolus is then propelled towards the esophagus.
What propels the bolus towards the esophagus in the pharygneal phase? (2)
1) Suprahyoid muscles will elevate the hyoid bone, blocking the airways –> Pressure will help propel bolus
2) Cricoid cartilage contacts, and opens the upper esophageal sphincter
Summary of Pharyngeal phase? (NLE–>HC)
- Nasal cavity sealed
- Laryngeal muscles close vocal cords
- Epiglottic blocks airways
- Suprahyoid bones elevate hyoid, help block airwyas
- Cricoid cartilege pulls backs, and opens the UES
What is gagging, choking, watery eyes and wet vocal quality associated with?
Issues in the pharyngeal phase
Chief function of esophagus?
Motility
What kind of muscle is in the UES?
Cricopharyngeal muscle
What is another name for the UES?
Pharyngeoesophageal junction
What is the main barrier in preventing laryngopharyngeal reflux?
UES
Describe the esophageal phase?
This autonomic phase is controlled by the glossopharyngeal, vagus and hypoglossal nerves. When the cricopharyngeal muscles relax, the bolus is passed through the UES into the esophagus, peristalsis carries the bolus down to the LES and finally into the stomach.
What does GERD stand for?
Gastroesophageal Reflux disease
What causes GERD?
When pressure in stomach>pressure in esophagus –> reflux of contents back through the LES
When ___ is lowered, gastric contents can flow backwards into the espohagus
LES pressure
When gastric acid and pepsin are found in the esophagus, what could this be indicative of?
Gastric acid and pepsin