Topic 2: Respiratory

Question 0

What is the nasal cavity?

Answer 0

Internal portion of the nose.

This is connected to the pharynx through internal nares (openings)

Question 1

What are the three structures of higher upper respiratory tract?

Answer 1

Structures located outside the thorax:

1) nasal cavity
2) pharynx
3) larynx

Question 2

What are the functions of the nasal cavity?

Answer 2

Receiving olfactory stimuli
Filters large dust particles
Warms and moistens incoming air

Question 3

What are the three main parts of the pharynx?

Answer 3

Nasopharynx: exchanges air with nasal cavity and moves particulate matter to mouth
Orophayrnx: serve as common passageway for air and food.
Laryngopharynx: connects oesophagus and larynx and serves as common passageway for air and food

Question 4

What is the larynx?

Answer 4

The voice box.

A short passageway that connects pharynx with trachea.

Question 5

What is the function of the glottis and epiglottis?

Answer 5

Act as trap doors to ensure that liquids and food do not go into the trachea

Question 6

What comprises the lower respiratory tract?

Answer 6

This is located almost entirely within the thorax

Contains trachea, bronchial tree and lungs

Question 7

What is the trachea?

Answer 7

Windpipe.

Connects the larynx with bronchi

Question 8

What is the role of the epithelial lining of the bronchial tree?

Answer 8

Acts as a defence mechanism known as the mucociliary escalator

Question 9

How does the mucociliary escalator work?

Answer 9

Cilia on the surface of the cells beat upwards in organised waves of on traction to expel foreign bodies.
Particles are also trapped within the mucous to be coughed out

Question 10

What is the main function of a cough?

Answer 10

Airway clearance (with the help of the mucociliary escalator.

Question 11

How can coughs be described?

Answer 11

Productive, chesty, wet, phlegmy

Non productive, dry, tickly, tight.

Question 12

What are the different durations of coughs?

Answer 12

Acute: 4 weeks

Chronic persistent cough (adult): >8 weeks

Question 13

When should coughs be referred to a medical practitioner?

Answer 13

Generally, patients presenting with coughs other than acute coughs (even without alarm symptoms).

Question 14

What causes a cough? (Mechanism)

Answer 14

Receptors located in the pharynx, larynx, trachea and bifurcations of the large bronchi are stimulated either by mechanical, irritant or thermal mechanisms.

A nerve impulse is carried (via Afferent pathways of vasal and superior laryngeal nerves) to the cough centre in the medulla. Efferent fibres of vagus and spinal nerves then carry the neural activity to the muscles of the diaphragm, chest walk and abdomen. These contract.
The glottis suddenly opens and a cough is created.

Question 15

What are the common causes of an acute cough?

Answer 15

Infection
Allergies
Upper airways cough syndrome (post natal drip)

Question 16

What are there clinical features of an acute viral cough?

Answer 16

Sudden onset associated with a fever.
Minimal sputum production
Symptoms worsen in evening.
Associated cold symptoms often present

These usually last between 7-10days

Question 17

What does a duration of a cough longer than 14 days indicate?

Answer 17

Post viral cough

Question 18

What other cough conditions should be eliminated in the differential diagnosis?

Answer 18

Acute:
Laryngotracheabronchitis (coup)
Upper airways cough syndrome

Chronic:
COPD
Asthma
Medicine induced cough or wheeze

Question 19

What is coup?

Answer 19

A less common cause of acute cough in children. Parainfluenza and respiratory syncytial viruses are the common cause.
Typically affecting infants 6-36 months old (peak incidence 12-24 months)
More common in boys.
Barking seal like cough generally at night and subsiding with a few hours. Typical occurs with a preceding history of URT infection.

Question 20

What is upper airways cough syndrome?

Answer 20

Aka post nasal drip is characterised by sinus or nasal discharge which flows behind the nose and into the throat.
Swallowing mucous or clearing throat more frequent than usual are common signs.
Allergies are a common cause. Allergen caused UACS is often non productive but worse at night and there are usually associated symptoms (sneezing, nasal discharge/blockage, conjunctivitis, itching of oral cavity)

Vasomotor rhinitis is another cause (odours, changes in temperature or humidity can set it off)

Post infectious UACS after an URTI is also a possibility

Question 21

What is COPD?

Answer 21

Serious chronic lung condition involving destruction of lung tissue and chronic bronchitis.

Most Common cause of chronic cough in adults and patients present with longstanding history of recurrent acute bronchitis with increasingly severe episodes.

Question 22

What is asthma?

Answer 22

Chronic inflammatory condition of airways characterised by coughing, wheeze, chest tightness and shortness of breath.
Can present solely as a non productive cough especially in children.
Symptoms can be worse at night.
Often associated with personal or family history of aropa, made worse by medicines like NSAIDs and beta blockers

Question 23

What is medicine induced cough or wheeze?

Answer 23

Many meds can cause bronchoconstriction which presents as as cough or wheeze.
ACE inhibitors are the most commonly assoc. with a cough.
The cough is not dose related and time of onset is variable .

NSAIDs MTX, amiodarone, beta blockers are other meds which can induce a cough

Question 24

What are examples of rare causes of cough?

Answer 24

Productive coughs: heart failure, Bronchiectasis, TB, pneumonia, carcinoma of lung, legionnaires disease

Non productive coughs: GORD, lung abscess

Spontaneous pneumothorax