Physiology in Dysphagia (ISS)

Question 1

Function of deglutition (swallowing)?

Answer 1

Process which moves food/liquid from the the mouth, through the pharynx and oesophagus, to the stomach; this takes 20 secs

Question 2

Requirements for normal swallowing?

Answer 2

Neuromuscular contraction (voluntary and involuntary control)

Absence of mechanical obstruction

Question 3

3 phases of swallowing?

Answer 3

1. Oral
2. Pharyngeal (shortest phase - 1 second)
3. Oesophageal (8-20 seconds)

Question 4

Control of the oral phase of swallowing?

Answer 4

VOLUNTARY and involves high cortical centres, muscles and cranial nerves V, VII and XII

Question 5

Other structures involved with the oral phase of swallowing?

Answer 5

Teeth - chewing of food

Lips - containment of food

Palate - allows simultaneous breathing and chewing, as it separate the oral and nasal cavities

Salivary glands - produce saliva to moisten food

Tongue - forms food bolus and pushes it posteriorly, into the pharynx

Question 6

Abnormalities that can affect the oral phase of swallowing?

Answer 6

Abnormalities of:
Mouth
Salivary secretions
Muscles of mastication
Neurological disorders, e.g: cerebral cortex or cranial nerves

Question 7

Control of the pharyngeal phase of swallowing?

Answer 7

Involuntary; it is controlled by brain stem centres and CN IX and X

Responses are initiated by food pressure on the pharyngeal pressure receptors; there is an afferent impulse to the swallowing centre in the medulla of the brain stem

Question 8

Common functions of the:
Soft palate
Tongue
Uvula
?

Answer 8

Prevent entry of food into the nasal passages as:
Soft palate rises
Tongue presses against the hard palate
Uvula presses against the back of the throat

Question 9

Common functions of the:
Larynx
Epiglottis
Vocal chords
Swallowing centre (brain)
Pharyngeal muscles
?

Answer 9

Prevent entry of food into the trachea:
Larynx is elevated
Epiglottis tilts
Vocal chords adduct across the glottis
Swallowing centre inhibits the resp centre
Pharyngeal muscles contract and forces bolus into the oesophagus

Question 10

Function of the upper oesophageal sphincter?

Answer 10

Opens to allow food into the oesophagus

Question 11

Control of the oesophageal phase of swallowing?

Answer 11

Involuntary; swallowing centre in the medulla is involved with closure of the UOS, once the bolus has entered the oesophagus

Question 12

Process of moving food from the pharynx to the stomach?

Answer 12

Bolus moves by peristaltic contractions, initiated by the swallowing centre in the medulla (via CN X)

Upper oesophagus - skeletal muscle contractions
Lower oesophagus - smooth muscle in distal oesophagus

LOS opens to allow passage and closes to prevent reflux

Question 13

Causes of dysphagia?

Answer 13

Lack of normality of muscles, cortical centres, brain stem centres and CN V, VII, IX, X and XII

Mechanical obstruction

Abnormal dentition and salivary function

Question 14

Characteristics of oropharyngeal (transit) dysphagia?

Answer 14

More difficulty swallowing LIQUIDS than solids. as liquid is more like to enter resp tract

Question 15

Examples of causes of oropharyngeal dysphagia?

Answer 15

Tonsillitis, pharyngitis

Stroke
Multiple sclerosis
Parkinson's disease
Motor neuron disease
Myasthenia gravis

Muscular dystrophy

Xerostomia (dry mouth - abnormal saliva production)

Obstruction by tumour/foreign body

Question 16

Symptoms of oral dysphagia?

Answer 16

Difficulty chewing/inadequately chewing food

Retention of food in the mouth

Sticking or pocketing of food in the mouth

Difficulty getting food to the back of the throat

Stranded phlegm

Drooling

Question 17

Symptoms of pharyngeal dysphagia?

Answer 17

Coughing while or immediately after eating or drinking

Nasal regurg of food & drinks

Gurgly sounding voice during/after eating/drinking

Sticking of food in the back of the throat

Aspiration - chest problems

Question 18

Describe oesophageal dysphagia

Answer 18

Inability to swallow solid foods and often described as food sticking before it reaches the stomach

Onset of symptoms is several secs AFTER swallowing begins

Question 19

What is dysphagia equally affecting liquids and solids from the outset likely to be?

Answer 19

Neuromuscular, e.g: achalasia

Question 20

What is dysphagia initially for solids likely to be?

Answer 20

Mechanical obstruction (intrinsic/extrinsic):

Intermittent, non-progressive oesophageal dysphagia to solids likely has a benign cause, e.g: GORD

Rapidly progressive oesophageal dysphagia likely has a malignant cause, esp. if assoc. with weight loss

Question 21

Symptoms of oesophageal dysphagia may include?

Answer 21

Sticking of food, e.g: in mid-chest or at the level of the epigastrium

Vomiting

Symptoms may occur several seconds after initiation of swallowing

History of heartburn and/or reflux

Chest symptoms caused by ASPIRATION

Weight loss

Question 22

Ix for dysphagia?

Answer 22

Blood tests, e.g: FBC, LFTs and U&Es

CXR

Endoscopy (look for obstructive oesophageal causes)

CT scan

Ba swallow or video fluoroscopy (assess oropharyngeal phases of swallowing)