Pulmonary

Question 1

Describe the pathophysiology of asthma.

Answer 1

Extrinsic
- pathogenesis of underlying inflammation is clear
- type I hypersensitivity develops
- allergen trigger mucosal mast cells to release mediators
- open epithelial junction
- antigen penetrates submucosal layer
- increased release of inflammatory mediators
- inflammatory cells attracted to area
- inflammatory mediators cause bronchial muscle
contraction, mucosal swelling, mucous production and
nerve stimulation resulting in bronchoconstriction

Intrinsic
- unclear but theorised associated with respiratory viral
respiratory infection or inhaled pollutants
-

Question 2

Describe the clinical manifestations of asthma.

Answer 2

Episodic dyspnea
Cough
Wheezing (difficulty with expiration, whistling noise)

Question 3

Explain how ventilatory function is measured by spirometry to evaluate airway obstruction in asthma.

Answer 3

.

Question 4

Identify the factors that predispose people to respiratory infection.

Answer 4

• Contact,
• droplet,
• inhaling the germs.
• Family members are sick.
• Cystic fibrosis increases chances.
• Nasogastric tube.

Question 5

Name the causative organisms of most upper respiratory tract infections.

Answer 5

rhino-, corona- and adenoviruses

Streptococcus pyogenes

Question 6

Give 2 reasons why treatment of the common cold is solely to reduce symptoms.

Answer 6

It is viral so anti-biotics don’t work.

To give comfort whilst getting better.

Question 7

Describe the cause of pharyngitis and a potentially serious complication.

Answer 7

Rhino, corona and adenoviruses.

• It can cause scarlet fever,
• Acute rheumatic fever,
• Acute glomerulonephritis.
• bronchitis
• pneumonia
• secondary bacterial infections

Question 8

Explain why vaccinations for influenza are not protective for long and describe the basics of treatment for influenza.

Answer 8

There are multiple strains of influenza and the virus (Myxovirus) undergoes antigenic shift (mutation)

• The basic treatment for influenza to take anti-viral drugs.
• Get the vaccine regularly
• Paracetamol
• Drink water
• Rest
• Supportive

Question 9

Describe the pathogenesis of lobar and bronchopneumonia.

Answer 9

Microorganisms reach lung via inhalation, aspiration of oropharyngeal secretions or spread from blood stream

Lobar pneumonia
- infection and consolidation confined to 1 or 2 lobes

Bronchopneumonia
- consolidation and infection occurs throughout lungs

Question 10

Explain why aspiration of gastric fluid causes serious damage to the lungs.

Answer 10

Aspiration of gastric fluids can carry bacteria into the lungs. Pneumonia often develops.

Question 11

Define pneumothorax

Answer 11

Partial or entire collapse of affected lung due to air in the pleural space.

Question 12

Explain why tension pneumothorax is life-threatening

Answer 12

The air cannot get out of the lung and therefore puts pressure on the heart.

Question 13

Describe how pleural effusions develop and why they are often associated with dyspnoea.

Answer 13

They are caused by pneumonia.

Fluid accumulation in the pleural space prevents full lung inflation → hypoxemia and dyspnea. Pain with breathing may occur with inflammatory causes.

Question 14

Define asthma

Answer 14

A chronic disorder of reversible airway obstruction

Question 15

Diagnoses of asthma

Answer 15

Patient history

Airway responsiveness assessed via inhalation challenge test with histamine, cholinergic agonists or cold air

Lung function tests are used to measure peak expiratory flow and the FEV1/FVC ratio

Question 16

Define pneumonia

Answer 16

Infection and inflammation within the lungs

Question 17

Name the most common causative organism of pneumonia

Answer 17

Bacteria, virus, fungi

Question 18

Indicate the significance of pneumonia as a hospital-acquired condition.

Answer 18

15- 30% of cases are hospital acquired.

Leading cause of death in infants and elderly
Major cause of death throughout world
Major cause of intensive care mortality

Question 19

Risk factors of pneumonia

Answer 19

lung disease (e.g. COPD),
smoking, 
immobilisation, 
altered consciousness,
immune suppression, 
alcoholism

elderly
children
underdeveloped nations,
malnourished, 
crowded and unhygienic environments

Question 20

Clinical manifestations of pneumonia

Answer 20

Fever
cough (progresses to productive cough)
chest pain
breathlessness,
rapid/shallow breathing 
rales

Question 21

2 causes of pneumothorax

Answer 21

Spontaneous
- Rupture of bleb or blister on lung surface secondary to asthma or infection/malignancy. Usually occurs in young people.

Traumatic
- Penetrating chest trauma and non-penetrating trauma (fractured rib) damage the pleural space and lung tissue (may also cause haemothorax).

Question 22

Define pleural effusions

Answer 22

Abnormal collection of fluid in the pleural cavity.

Question 23

Difference in severity between upper and lower respiratory infections.

Answer 23

Upper respiratory tract infections (URTIs) – usually not
life threatening

Lower respiratory tract is normally sterile, thus infections
often serious

Question 24

What categories do the strains on influenza affect

Answer 24

Influenza A affects humans and wide range of animals. Cause of epidemics and pandemics.

Influenza B only affects humans. Cause epidemics but not pandemics

Question 25

What are the antigens on the surface envelope of Myxovirus

Answer 25

haemagglutinin (H) | neuraminidase (N)

Question 26

Difference between antigenic drift and antigenic shift

Answer 26

Antigenic drift are small constant changes in H and N Antigenic shift are major, sudden and unpredictable changes in H and N that lead to a new strain of virus

Question 27

Pathogenesis of Influenza

Answer 27

Transmission by droplet, highly infectious Virus adheres to upper respiratory tract epithelium via the H proteins. 1 to 3 days – fever, chills, malaise, muscle pain; runny nose, sore throat and cough may follow; recovery in 1 to 3 weeks

Question 28

Acute Bronchitis

Answer 28

* Caused by virus * Initial symptoms similar to pneumonia * Self-limiting * Treatment symptomatic – no antibiotics * Bacterial bronchitis occurs with underlying disease

Question 29

Bronchiolitis

Answer 29

Childhood form of bronchitis • under 2 yrs • Respiratory Syncytial Virus (RSV) most common cause • Highly infectious • Fever, coryza, cough, asthma-like symptoms • Healthy infants recover well while premature infants with low birth weight may display severe and possibly fatal progression

Question 30

Disorders which limit expiratory flow

Answer 30

``` asthma bronchitis emphysema brochiectasis cystic fibrosis ```

Question 31

Cystic fibrosis

Answer 31

* Autosomal recessive condition linked to gene mutation of transmembrane regulator (CFTR) that functions as a chloride ion channel * Cl- is retained in cells which leads to water and Na+ absorption from mucosal surface leading to ↑ viscosity of mucous * Clinical manifestations include excessive secretion viscous fluid from epithelial glands of respiratory, gastrointestinal and genitourinary tracts * Excessive secretions cause accumulation of viscous bronchial mucous, impaired mucociliary clearance and lung infections * Major cause of chronic (non-reversible) respiratory disease in children

Question 32

Define atelectasis

Answer 32

collapse of lung segment

Question 33

Define transudate fluid

Answer 33

clear fluid from congested lungs due to heart failure, renal and/or liver disorder.

Question 34

Define haemothorax

Answer 34

escape of blood into pleural space due to chest trauma, | malignancy and/or vessel rupture.

Question 35

Define exudate fluid

Answer 35

protein and inflammatory cells that arise from infection, cancer or DVT.

Question 36

Use of prophylactic anti-inflammatory drugs

Answer 36

- Preventative measure for asthma - Crucial for moderate to severe asthma and taken on a regular basis:

Question 37

Use of bronchodilators

Answer 37

symptomatic relief

Question 38

Use of glucocorticoids

Answer 38

Beclomethasone (inhaled) and Prednisone (oral) ↓inflammatory mediators ↓inflammatory cell infiltration ↓ oedema and mucous secretions ↑β2 receptors and sensitivity to β2 agonists • Inhaled drug avoids severe adverse effects

Question 39

Types of prophylactic anti-inflammatory drugs

Answer 39

– Glucocorticoids (anti-inflammatory) – Leukotriene (pro-inflammatory) modifiers – Cromolyn (mast cell stabiliser) – IgE antagonists

Question 40

Types of bronchodilators

Answer 40

– Beta2 adrenergic agonists – Methylxanthines (↓ airflow obstruction, airway hyperresponsiveness, and airway inflammation) – Anticholinergics

Question 41

Use of leukotriene modifier

Answer 41

– introduced late 90’s; well tolerated – leukotriene receptor antagonist – used for intrinsic/extrinsic asthma and allergic rhinitis

Question 42

Use of Cromolyn

Answer 42

– ↓histamine release and ↓inflammatory cell activity – low incidence of adverse effects – less effective than corticosteroids

Question 43

Use of IgE antagonist

Answer 43

– second line drug – monoclonal antibody attaches/inhibits IgE – associated with a number of adverse effects including anaphylaxis

Question 44

Use of Methylxanthines

Answer 44

– Widespread use diminished as other treatments safer – Mechanism of smooth muscle relaxation is unclear, provide less effective but longer duration of action than β2 agonists – Adverse effects include vomiting, diarrhoea, restlessness, insomnia

Question 45

Use of Muscarinic Antagonists

Answer 45

– Recommended for COPD but also used for asthma, – Administered via inhalation which localises drug in lungs and thus avoids adverse effects

Question 46

Types of inhalers

Answer 46

``` Metered-Dose Inhalers (MDI’s) – hand held pressurised devices – require hand-breath coordination – 10% of the drug released reaches lungs – use of a spacer improves delivery ``` Dry-Powder Inhalers (DPI’s) – not pressurised/ breath activated – little coordination required – 20% of dose reaches lungs

Question 47

Classification of asthma

Answer 47

Intermittent Mild Moderate Severe | ≤ 2 d/wk 2-7 d/wk daily Through the day

Question 48

Why does frequent use of bronchodilators cause tachycardia

Answer 48

While the drug is selective for beta 2 receptors it does have some beta 1 (cardiac receptors) action. Therefore in higher doses some beta 1 stimulation occurs leading to tachycardia.