GI6 - Salivation & Swallowing

Question 1

6 features of the composition of saliva

Answer 1

1. ) Enzymes - amylase, lingual lipase
2. ) Immune Proteins - IgA, lysozyme, lactoferrin
3. ) Salivary Mucins - lubrication and protection of the oral cavity
4. ) Ions - rich in potassium and bicarbonate
   - pH is slightly acidic
5. ) Mostly Water
6. ) Hypotonic

Question 2

6 functions of saliva

Answer 2

1. ) Begins Digestion - contains salivary and lingual enzymes
2. ) Hydrate Food - making it easier to form a bolus
3. ) Solvent - dissolves molecules, allowing taste
4. ) Healthy Teeth - protects dental decay
5. ) Infection Transmission - contains lots of bacteria
6. ) Speech

Question 3

3 features of xerostomia

Definition
Causes x4
Symptoms x3

Answer 3

1. ) Definition - dry mouth resulting from reduced or absent saliva flow
2. ) Causes - blocked nose, drugs e.g. antidepressants, salivary gland surgery, radiotherapy
3. ) Symptoms - bad breath, ulcers, speech changes

Question 4

3 features of the salivary glands

Salivary Ducts
Neural Control
Parotiditis

Answer 4

1. ) 3 Glands - parotid, submandibular, sublingual
   - sublingual duct opens laterally on the floor of mouth
   - submandibular duct opens medially on the “
   - parotid duct penetrates buccinator muscle
2. ) Neural Control - parasympathetic is the main innervation which increases production
   - sympathetic can stimulate secretion of small amounts of saliva but its main role is vasoconstriction to block saliva production
3. ) Parotiditis - inflammation of the parotid glands
   - stones can block parotid ducts which can cause pain while eating

Question 5

3 phases of swallowing

Oral Preparatory
Pharyngeal
Oesophageal

Answer 5

1. ) Oral Preparatory Phase - voluntary
   - movements of the tongue pushes bolus towards the back of the oral cavity, towards the oropharynx
   - this triggers the pharyngeal phase
2. ) Pharyngeal Phase - involuntary
   - closing off the nasopharynx and epiglottis
   - food is pushed downwards into the oesophagus
3. ) Oesophageal Phase - involuntary
   - closure of the upper oesophageal sphincter
   - peristaltic wave carries bolus downwards into oesophagus

Question 6

5 steps in the pharyngeal phase of swallowing

Closing Off Nasopharynx
Closing the Epiglottis
Movement of Food Bolus
Protection of Airway
Upper Oesophageal Sphincter

Answer 6

1. ) Closing Off Nasopharynx - from the oropharynx
   - caused by elevation of the soft palate
2. ) Closing the Epiglottis - prevents aspiration of food
   - caused by elevation of the larynx:
   - contraction of the suprahyoid muslces and the internal/longitudinal pharyngeal muscles
3. ) Movement of Food Bolus - towards the oesophagus
   - action of the pharyngeal constrictors
4. ) Protection of Airway - vocal cords adduct
   - breathing temporarily ceases

5.) Upper Oesophageal Sphincter Opens

Question 7

Dysphagia

Oesophageal Dysphagia
Oropharyngeal Dysphagia
Malignant Dysphagia
Other Red Flag Symptoms

Answer 7

1. ) Oesophageal Dysphagia - food stuck in the throat
   - obstruction: tumour, stricture, inflammation, can be classed as extraluminal, intraluminal, or luminal
   - neuromuscular: presbyoesophagus (abnormal shape), achalasia, dysmotility
   - OGD used to exclude obstructive causes
   - barium swallow or manometry for neuromuscular
2. ) Oropharyngeal Dysphagia - food can’t enter throat
   - problems with tongue muscle coordination
   - often as a result of neurological disease e.g. stroke
   - video-fluoroscopy can be used to assess swallowing
   - may need enteral feeding tube if unsafe swallowing

3.) Malignant Dysphagia - usually squamous cell carcinoma or adenocarcinoma.

4. ) Other Red Flag Symptoms - ALARM
   - Anaemia, Loss of Weight, Anorexia, Recent onset of progressive symptoms, Masses/Malaena