biochem

Question 1

causes of hyperkalaemia

Answer 1

↑intake: oral, parenteral, transfusion
transcellular movement: rhabdomylysis, DKA, acidosis
↓excretion: AKI, drugs (spironolactone, NSAIDs, ACEi, ARBs), Addison’s

Question 2

management of hyperkalaemia (incl. dosage)

Answer 2

calcium gluconate (10ml 10%) 
10 units insulin + dextrose (100ml 20%)
neb salb  
\+ treat underlying cause
IV sodium bicarb if acidotic

Question 3

ECG findings hyperkalaemia

Answer 3

tented T waves
long PR interval
small / absent P waves
broad QRS

Question 4

causes of hypercalcaemia

Answer 4

suppressed PTH: malignancy (mets, non-small cell lung cancer, multiple myeloma), sarcoidosis, vit D excess, thyrotoxicosis
normal / high PTH: primary / tertiary hyperparathyroidism

Question 5

management hypercalcaemia

Answer 5

IV saline
bisphosphonates (alendronate)
steroids in sarcoidosis

Question 6

causes of hypokalaemia

Answer 6

GI: vomiting, diarrhoea
renal: Conn’s syn, diuretics (non K-sparing e.g. furosemide)
redistribution into cells: alkalosis, drugs: beta-agonists, insulin, digoxin toxicity

Question 7

causes of hypernatraemia

Answer 7

hypovolaemic: losses
dehydration 
GI: vomiting, diarrhoea
renal: loop diuretics 
skin: burns, sweating
osmotic diuresis: HHS, glucose, mannitol  
euvolaemic: diabetes insipidus
hypervolaemic: conn's syn

Question 8

causes of hyponatraemia

Answer 8

hypovolaemic: losses
GI: vomiting, diarrhoea
renal: thiazide diuretics
euvolaemic: SIADH, hypothyroidism, adrenal insufficiency
hypervolaemic: cardiac failure, cirrhosis, nephrotic syn

Question 9

causes of high anion gap metabolic acidosis

Answer 9

DKA 
paracetamol
salicylates 
alcohol
lactic acidosis e.g. in tissue hypoxia 
hyperkalaemia

Question 10

causes of raised urea

Answer 10

AKI

upper GI bleed