Renal physiology Flashcards
Which part of kidney is most hypoxic?
Renal medulla
Cause of papillary necrosis
Sick cell disease
Diabetes
Site of hydroxylation in kidney
PCT
Where in kidney is calcium absorbed?
DCT
Which part of kidney senses low sodium?
Macula densa
What causes vasoconstriction of afferent arteriole?
NSAID acting on alpha 1 receptors
What causes vasoconstriction of efferent arteriole?
How to measure GFR?
Inulin
How to measure renal blood flow?
PAH
Best marker (non clinical) of GFR?
EDTA
Net filtration pressure
NFP = glomerular hydrostatic pressure - Bowman’s capsule pressure - glomerular oncotic pressure
Sign of acute tubular necrosis
Muddy brown casts in urine (iron)
Causes of acute tubular necrosis
Hypovolaemia
Sepsis
Drugs - ahminoglycosides, contrast, chemotherapy
Biochem due to post-renal obstruction
Hypokalaemia
Metabolic alkalosis
Where do osmotic diuretics (mannitol) work?
Top to bottom - important
Proximal and descending loop
Where do loop diuretics (furosemide) work?
Inhibit Na/K/Cl = ascending limb
Side effect of loop diuretics
Ototoxicity
Where to thiazide diuretics work?
Inhibit Na/Cl - distal tubule
Side effects of thiazide diuretics
Hyponatraemia
Hypercalcaemia
Where do potassium sparing diuretics work?
Na and water collection - collecting duct
Side effect of potassium sparing diuretics
Hyperkalaemia
Cause of normal anion gap
Fistula
Uterogastric condutis
Saline administration
Hyperparathyroidism
Diarrhoea
Renal tubular necrosis
Spironolactone
Cause of high anion gap
Methanol
Uraemia
DKA
Lactic acidosis
Isoniazid
Salicylate
Antifreeze
