electrolyte cases Flashcards
what type of hyponatraemia does this patient have - and the causes for it
hypovolaemic - loss of water and Na
D and V
diuretics
salt losing nephropathy
mx of hypovolaemic hyponatraemia
volume replacement with 0.9% saline
what type of hyponatraemia does this patient have - and the causes
hypervolaemic hyponatraemia
cardiac failure
cirrhosis
nephrotic syndrome
mx of hypervolaemic hyponatraemia
fluid restriction
treat underlying cause
type of hyponatraemia
hypervolaemic - due to cirrhosis
type of hyponatraemia in this pt and causes
euvolaemic
hypothyroidism = less cardiac contractility = more water resorption
adrenal insufficiency
SIADH
mx - treat underlying cause eg thyroxine replacement
how do you differentiate between the types of hyponatraemia
type of hyponatraemia in this pt, causes, dx test and mx =
euvolaemic
adrenal insufficiency
short synacthen test
mx - hydrocortisone and fludrocortisone
type of hyponatraemia in this pt, causes, dx test
euvolaemic
SIADH
plasma and urine osmolality
things need for dx of SIADH
no hypovolaemia
no hypothyroidism
no adrenal insufficiency
reduced plasma osmolality adn increased urine osmolality
causes of SIADH
CNS
lung
drugs - SSRI, TCA, opiates, PPI, carbamazipine
tumours
surgery
causes of hypernatraemia
unreplaced water loss:
* GI losses, sweat
* Renal loss - osmotic diuresis, reduced ADH release/action ie DI
pt cannot control water intake - ie children/elderly
summarise ADH
ix in suspected DI
Serum glucose (exclude diabetes mellitus)
Serum potassium (exclude hypokalaemia)
Serum calcium (exclude hypercalcaemia)
Plasma & urine osmolality
Water deprivation test
what are you thinking with HTN and low K
hyperaldosteronism
need aldosterone:renin ratio
