Mouth, pharynx and oesophagus Flashcards

1
Q

What are the functions of saliva?

A

Lubricates food for swallowing
Aids taste
Begins digestion
Protects oral environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What enzymes are in saliva that aid digestion?

A
Alpha amylase (digestion of starch) 
Linguinal lipase (digestion of lipids)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the composition of saliva?

A

Hypotonic
Lower osmolarity than plasma
Contains water, mucus, digestive enzymes, antibacterial agents, high concentrations of potassium, bicarbonate and calcium, low concentrations of sodium and chloride

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the pH of saliva?

A

6.2-8.0 (dependent on whether it is stimulated or not)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How much saliva is produced per day?

A

800-1500ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the salivary glands?

A
  1. Parotid (serous saliva)
  2. Sublingual (mucus saliva)
  3. Submandibular (mixed saliva)

[Nb. Also buccal glands and Von Ebner’s glands on tongue]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do Von Ebner’s glands produce?

A

Lingual Lipase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the structure of salivary glands?

A

Appearance like bunch of grapes
Acini (lined by acinar cells) produce initial secretion
Duct cells modify secretions
Myoepithelial cells contract to eject saliva

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens during saliva production?

A

Isotonic ultrafiltrate from blood plasma is diffused through acinar cells where it is mixed with enzymes - saliva then drains into ducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens during ductal modification?

A

Overall net absorption of solute but not water (ductal cells impermeable to water) leaving a hypotonic solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why does the composition of saliva differ when stimulated compared to resting?

A

At rest, saliva flow rate is lower allowing more time for ductal modification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is Xerostomia?

A

Dry mouth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the key signs and symptoms of Xerostomia?

A
Burning sensation in mouth 
Dry throat/ tongue/ lips 
Difficulty swallowing and speaking 
Altered taste 
Halitosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are potential causes of Xerostomia?

A
Medication side effects 
Dehydration 
Anxiety 
Sjogren's Syndrome 
Radiation therapy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 5 taste classifications?

A
Sweet
Sour 
Bitter 
Salty 
Umami
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where are taste buds found?

A

Tongue (papillae)
Palate
Larynx
Pharynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What cells do taste buds contain?

A

Taste receptor cells
Supporting cells
Basal cells (replace cells sloughed off the tongue)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What type of receptors are taste receptor cells?

A

Chemoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is mastication?

A

Chewing - breaking up food to increase surface area for enzyme action - creates bolus for swallowing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What muscles are involved in mastication?

A

Masseter muscles
Temporalis muscles
Medial and lateral pterygoid muscles
Suprahyoid muscles

21
Q

What are the 4 points of oesophageal narrowing?

A
  1. Junction between pharynx and oesophagus
  2. Crossing with aortic arch
  3. Where oesophagus is posterior to the left main bronchus
  4. Oesophageal hiatus in the diaphragm
22
Q

What kind of sphincter is the LOS?

A

Physiological

23
Q

What is the function of the LOS?

A

Prevents reflux of gastric contents into the oesophagus

24
Q

What are the components of the LOS that allow it to function normally?

A
  1. Right crus of diaphragm
  2. Acute angle at which oesophagus enters stomach
  3. Mucosal folds at gastro-oesophageal junction
  4. Positive intra-abdominal pressure
25
Q

What are the features of GORD?

A
Reflux of acidic contents through LOS 
Heartburn 
Acid brash 
Regurgitation 
Water brash
26
Q

What is Barrett’s Oesophagus?

A

Metaplasia of squamous epithelium of oesophagus to columnar mucosa

27
Q

What does Barrett’s Oesophagus increase likelihood of?

A

Oesophageal Adenocarcinoma

28
Q

What are the 3 phases of swallowing?

A
  1. Oral phase
  2. Pharyngeal phase
  3. Oesophageal phase
29
Q

What happens during the oral phase of swallowing?

A

Tongue moves bolus towards oropharynx
Cranial nerves relay information to swallowing centre in medulla
Swallowing reflex initiated

30
Q

Which phase of swallowing is voluntary?

A

Oral phase

31
Q

What happens during the pharyngeal phase of swallowing?

A

Soft palate elevates and blocks nasopharynx
Upper oesophageal sphincter opens
Food propelled through sphincter into oesophagus

32
Q

What happens during the oesophageal phase of swallowing?

A

Upper oesophageal sphincter closes to prevent reflux
Primary peristaltic wave coordinated by swallowing reflex propels food down oesophagus
Lower oesophageal sphincter relaxes

33
Q

What is achalasia?

A

Loss of coordination of peristalsis of lower oesophagus and spasm of LOS

34
Q

What is Achalasia characterised by?

A

Intermittent dysphagia
Regurgitation
Retrosternal chest pain

35
Q

What is the sympathetic innervation to the salivary glands?

A

Superior Cervical Ganglion (part of paravertebral chain)

Nb. Sympathetic stimulation INHIBITS saliva secretion

36
Q

What is the parasympathetic innervation to the parotid gland?

A
  1. Begins with glossopharyngeal (CN IX)
  2. Glossopharyngeal synapses with Otic Ganglion
  3. Auriculotemporal nerve carries parasympathetic fibres from Ganglion to parotid gland

Nb. Parasympathetic stimulation INCREASES saliva secretion

37
Q

What is the parasympathetic innervation to the submandibular gland?

A
  1. Originates from superior salivatory nucleus (through pre-synaptic fibres which travel through chorda tympani branch of CN VII)
  2. Chorda Tympani unifies with Lingual branch of CN Vc
  3. Synapses at submandibular Ganglion
  4. Post Ganglionic innervation from secretomotor fibres
38
Q

What is the parasympathetic innervation to the sublingual gland?

A
  1. Originates from superior salivatory nucleus (through pre-synaptic fibres which travel through chorda tympani branch of CN VII)
  2. Chorda Tympani unifies with Lingual branch of CN Vc
  3. Synapses at submandibular Ganglion
  4. Post Ganglionic innervation from secretomotor fibres
39
Q

What is the clinical term for painful swallowing?

A

Odynophagia

40
Q

What problems in the mouth can make swallowing difficult?

A

Problems with chewing and pushing food back including muscles of mastication, tongue, dental problems or lack of saliva

41
Q

What problems with the pharynx can make swallowing difficult?

A

Obstructions (e.g. tonsillitis or malignancy)

42
Q

What problems with the oesophagus can make swallowing difficult?

A
External obstruction (e.g. from trachea, thyroid goitre, left atrium) 
Internal obstruction (e.g. malignancy, foreign body) 
Oesophagitis (infection or ulcers) 
Abnormal motility (e.g. achalasia or scleroderma)
43
Q

What is scleroderma?

A

Smooth muscle is replaced by fibrous tissue leading to strictures

44
Q

What problems with the stomach can make swallowing difficult?

A

Malignancy (esp. in cardia region)

45
Q

What neuromuscular problems can make swallowing difficult?

A

Stroke
Neurodegenerative disorders (e.g. MND, MS)
Myasthenia Gravis
Syringobulbia (fluid filled cavities in spinal cord and brainstem)

46
Q

What signs and symptoms indicate dysphagia?

A

Coughing/ choking
Gurgling
Shortness of breath/ signs of chest infection (e.g. due to aspiration)
Holding food in mouth/ not chewing
Food/ drink falling out of mouth
Weight loss (e.g. due to being scared to eat)

47
Q

What is aspiration pneumonia?

A

LRTI due to inhalation of material from GI tract into respiratory tract

48
Q

What is progressive dysphagia indicative of?

A

[Dysphagia initially for more solid foods and then for softer foods as well]
Indicates an obstructive lesion (e.g. benign or malignant strictures, foreign body, oesophageal webs) or an external obstruction (e.g. thoracic aortic aneurysm, retrosternal goitre)