posterior pituitary triggers Flashcards
F8 and vWF release
function of ADH
how do ADH levels look in adrenal insufficiency
adrenal insufficiency = low cortisol = high ADH
hyponatremia, hypo-osmolality, euvolumic
SIADH
Fluid restriction is used to correct what
used for SIADH to correct hyponatremia
central pontine myelinolysis
occurs when severe hyponatremia is treated too quickly, results in permanent neurological deficits
prevented by monitoring magnitude of daily plasma Na rise
how quickly can sodium be raised in a situation of emergent hyponatremia
Raise serum Na by 0.5-1 mEq/h, no more than 10-12 mEq in 24 hours. MAX serum should only be 125-130.
what kind of saline is used for aggressive hyponatremia treatment
3% hypertonic saline
furosemide
loop diuretic used in treatment of acute hyponatremia to increase excretion of free water.
used in combination with hypertonic saline to limit treatment induced volume expansion
vasopressin-2 receptor antagonists used when
used for treatment of acute hyponatremia with moderate symptoms in combination with:
3% hypertonic saline
loop diuretics (furosemide)
water restrciton (500-1200ml)
reduces number of aquaporin-2 water channels in collecting duct
MOA of vasopressin-2 receptor agonist
dual V1a and V2 antagonist
Conivaptan
(parenteral aquaretic/vasopressin receptor antagonist)
V2 receptor antagonist. oral.
tolvaptan
Aquaretic/vasopressin receptor antagonist
tolvaptan and conivaptan indicated for
euvolemic and hypervolemic hyponatremia
AVOID in hypovolemic hyponatremia
deficiency and/or resistance to vasopressin
cause of DI
increased thirst w urine of low specific gravity
DI
pyelonephritis, amyloidosis, myeloma, sjogrens
all acquired causes of nephrogenic DI
X linked
congenital nephrogenic DI
normal secretion of ADH but they still have polyuria
nephrogenic DI
generally in the last trimester of pregnancy or puerpium
vasopressinase-induced DI
the presence of an enzyme that can destroy vasopressin
Vasopressinase-induced DI
this enzyme CANNOT destroy synthetic desmopressin
aggravation with high dose corticosteroids
DI
vasopressin challenge test
how is it done, what is it for
- Desmopressin acetate given.
- Urine volume measured after 12 hours and 24 hours.
- Central DI should have significant reduction in both thirst and polyuria.
vasopressin test with a modest fluid restriction is used when, what results are positive
used in nephrogenic DI, positive result shows high vasopressin levels
(someone please check this)
may be d/t autoimmune hypothalamic AVP secreting cells
primary DI
