-
pituary gland
adenohypophysis
- anterior lobe
- 70% of gland
- releases 6 hormones to target lands
- - GH, ACTH, TSH, prolactin, FSH, LH
- production and release reg. by hypothalmus
-
pituitary gland
neurohypophysis
- posterior lobe
- storage site
- secretes oxytocin and ADH
- - synthesis is in hypothalamus, stored in posterior pituary
-
diabetes indipidus
- deficiency or absence of ADH- cental DI
- inability to respond to ADH- nephrogenic DI
- - kidney no longer responds to ADH
-
DI
patho
- ADH release is stimulated by OSMO receptors in hypothalmus, baroreceptors in carotid, aortic arch
- decr ADH leads to lg amount of dilute urine--- no signal to stop
- specific gravity is low
-
DI
classic
- dilute, polyuria
- intense thirst
- r/t dec ADH
-
DI
manifestations/DX tests
- sudden polyuria nocturia
- polydipsia wt loss
- fatigue constipation
- dilute urine incr serum osmo (is incre b/c loss of blood)
- water deprivation test: 8-12 hours nothing to drink0 to see if output reduce
-
DI
management
- assess I&O, daily wt
- assess dehydration
- pt education
- - life long tx (central)- don't know what it is
- - nephogenic: renal- tx underlying cause
- - medical id
-
DI
management meds
- synthetic ADH
- -DDAVP intranasal, SC, IV- vasopressin
- vasopressin
- - pitressin intranasal, SC, IV: vasoconstriction, careful w/pt w/cardiac
- thiazide diuretic- mild form, incr affects of ADH
-
SIADH
- inapproriate incr release of ADH leads to:
- water intoxication, hypotonicity of plasma
- fluid expansion
- hypoatremia
-
SIADH causes
- neoplastic tumors- esp lung- tumor stimulates ADH production
- resp disorders- chronic
- hyperpitutarism
- renal disorders
- drugs- chemo/antineoplastic drugs, oral hypoglycemic, thiazide duirec, ssri
-
SIADH
- incr ADH leads to volume
- Na is lost in urine
- result is
- decre serum osmo
- h20 intoxication (fluid retention)
- hypoantremia
-
SIADH
s/s dx test
- acute rapid neuro chx- memory, mental chx
- - dec LOC
- - Loss of DTR
- - seizures to coma
-
SIADH chronic
- hypoatremia
- weight gain
- incr urine osm- kidney not working??
- CNS chx, h/a mild/gradual
- GI: n/v
-
SIADH: management
acute
- NA< 120 = CNS effects= emergency
- incre serun NA, not too rapidly
- - 3-5% NS w/na, IV lasix
- D/C drugs: if med induced
- becareful of lytes- for hypo kal/atremia
-
SIADH management chronic
- fluid restriction 500-100 m/d
- declomycin- interfers w/ADH se suprainfection
- monitor I&O, wt, lytes, neuro s/s
- teaching about fluid restriction, med, f/u
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