Respiratory

Question 0

Normal pH of pleural fluid

Answer 0

7.6

Question 1

Light’s criteria

Answer 1

Pleural fluid is an exudate if one or more of the following criteria are met:

1. Pleural fluid protein divided by serum protein >0.5
2. Pleural fluid LDH divided by serum LDH >0.6
3. Pleural fluid LDH more than two-thirds the upper limits of normal serum LDH

Question 2

A pleural pH of <7.2 with a normal blood pH is usually found in:

Answer 2

• pleural infections
• empyema
• TB
• malignancy
• oesophageal rupture

Question 3

A low glucose level <3.3 mmol/L in pleural fluid is usually seen in:

Answer 3

• empyema
• rheumatoid arthritis
• SLE
• TB
• malignancy
• oesophageal rupture

Question 4

What result from a sodium chloride sweat test would indicate cystic fibrosis?

Answer 4

Sodium chloride >60 mmol/L

Question 5

In the early stages of cystic fibrosis, which organisms colonise and infect the lung parenchyma? With chronicity, which ones take over?

Answer 5

Early - S. aureus and H. influenza

Late - P. aeruginosa and Burkholderia cepacia

Question 6

Which drugs can cause pulmonary fibrosis?

Answer 6

Amiodarone, bleomycin, bulsulfan, nitrofurantoin, methotrexate and sulfasalazine.

Question 7

Hypersensitivity pneumonitis

Answer 7

Aka extrinsic allergic alveolitis (EAA)
Occurs as a result of inhalation of organic allergens.
- Farmer’s lung (mouldy hay)
- Bird/pigeon fancier’s lung (feathers and bird droppings)
- Mushroom picker’s lung (mushroom compost)
- Malt worker’s lung (mouldy barley)

Question 8

What is the treatment for pulmonary Aspergillus spp. infection?

Answer 8

Amphotericin B, voriconazole, itraconazole or caspofungin.

Fluconazole is not effective against Aspergillus spp.

Question 9

What type of broncogenic carcinoma can cause hyponatraemia?

Answer 9

Small cell carcinomas can produce ectopic ADH hormone - paraneoplastic syndrome causing SIADH.

Question 10

Severity of COPD definitions

Answer 10

Mild: FEV1/FVC < 0.7, FEV1 % predicted > 80%
Moderate: FEV1/FVC < 0.7, FEV1 % predicted 50-79%
Severe: FEV1/FVC < 0.7, FEV1 % predicted 30-49%
Very severe: FEV1/FVC < 0.7, FEV1 % predicted < 30%

Question 11

Initial inhaled therapy for COPD

Answer 11

SABA or SAMA

Question 12

Regular nebulised salbutamol is commonly associated with what electrolyte disturbance?

Answer 12

Hypokalaemia

Question 13

Standard TB drug regimen

Answer 13

Isoniazid, rifampicin, ethambutol and pyrazinamide for 2 months.
Isoniazid and rifampicin for 4 months.

Question 14

What side effects is isoniazid associated with?

Answer 14

• Peripheral neuropathy caused by depletion of vitamin B6 (supplementation usually given)
• Rash
• Deranged liver function
• CNS effects
• Sideroblastic anaemia

Question 15

What side effects is pyrazinamide associated with?

Answer 15

• Arthralgia
• Hepatoxicity
• Gastro disturbances
• Rash
• Pruritis
• Sideroplastic anaemia

Question 16

What side effects is rifampicin associated with?

Answer 16

• Orange-red coloured urine and tears
• Hepatoxicity
• Fever
• GI disturbances
• Rash

Question 17

What side effects is ethambutol associated with?

Answer 17

• Optic neuritis
• Red-green colour blindness
• Peripheral neuropathy
• Vertical nystagmus

Question 18

Diagnostic criteria for ARDS

Answer 18

1. Acute onset
2. Bilateral infiltrates present on chest X-ray
3. Pulmonary capillary wedge pressure of < 200