Respiratory Diagnostic Tests

Question 1

Causes of metabolic acidosis

Answer 1

Loss of bicarbonate : diarrhoea, pancreatic drainage, billary drainiage, carbonic anhydrase inhibition, renal tubular acidiosis (type 2)

Increased acid: Sepsis, diabetic ketoacidosis, salicylate intoxication, methanol intoxication,

Impaired excretion: renal failure, renal tubular acidosis (type 1), adrenal insufficiency

Question 2

Causes of respiratory acidosis

Answer 2

Reduced respiratory drive - impaired consciousness, brain stem pathology, life-threatening resp illness

Question 3

What is a normal anion gap (met acidosis)?

Answer 3

Hco3 lost is replaced with cl

Get a hyperchlorimic acidosis

Question 4

Causes of a normal anion gap met acidosis?

Answer 4

Cage

Chloride
Acetazolamide/addisons
GI loss
Extras : RTA, ingestion of oral acidifying salts, recovery phase of DKA

Question 5

Causes of a high anion gap metabolic acidosis?

Answer 5

Cat mud piles

CO, CN,
Alcoholic ketoacidosis and starvation ketoacidosis
Toluene
Metformin, methanol
Uraemia
DKA
Paracetamol, 
Iron, isoniazid,
Lactic acidosis
Ethylene glycol
Salicylate

Question 6

Lung biopsy showing hyphae with vascular invasion and surrounding tissue necrosis… what’s the diagnosis?

Answer 6

Aspergillosis

Question 7

Bronchoalveolar lavage showing CD4 cells suggests?

Answer 7

Sarciodosis

Question 8

Bronchoalveolar lavage showing Eosinophils cells suggests?

Answer 8

Allergic bronchopulmonary aspergillosis

Question 9

Bronchoalveolar lavage showing Neurophils suggests?

Answer 9

Pneomonia

Interstitial lung disease

Question 10

Bronchoalveolar lavage showing marked lymphocyctosis suggests?

Answer 10

Hypersensitivity pneumonitis

Question 11

What conditions have a raise DLCO?

Answer 11

Asthma
Polycythemia
Pulmonary haemorhage 
After exercise 
Left to right shunts

Question 12

What counts as a significant bronchodilator response in reversibility testing?

Answer 12

Increase FEV1 >12%