Week 1 - Pituitary Disorders Flashcards
what hormone does the posterior pituitary store and secrete
- ADH
what is the fnxn of ADH
- plays major role in regulation of water balance and osmolarity
- plays major role in how the body retains water thru the kidneys
what are the two primary disorders of the pituitary gland
- syndrome of inappropriate antidiuretic hormone (SIADH)
- diabetes insipidus
what is SIADH
- condition caused by too much ADH
* think: Syndrome of Increased ADH*
what effect does increased ADH have on the kidneys? how does this effect intravascular fluid volume?
= increased water reabsorption in renal tubules
= increased intravascular fluid volume
how does increased ADH effect sodium and serum osmolality in SIADH
= dilutional hyponatremia & decreased serum osmolality
how would SIADH effect a pt’s BP? urine output? body weight?
- hypertension
- cause low urinary output with high specific gravity (very concentrated)
- increased body weight
what symptoms could the dilutional hyponatremia during SIADH cause? (9)
- muscle & abdominal cramps
- weakness
- vomiting
- seizures
- muscle twitching
- lethargy
- decreased LOC & confusion
- headaches
- coma if severe
1 kg of weight = ____ fluid
1kg = 1L of fluid
what should nurses monitor for a pt with, or possibly with, SIADH (10)
- LOC
- VS
- I&O
- low urine output w high specific gravity
- increased daily weight
- low K and Na lvls
- heart and lung sounds
- neurological assessments for decreased LOC
- observe for signs of hyponatremia
why should a nurse monitor heart and lung sounds for a pt with SIADH
- due to fluid overload which could cause pulmonary edema, etc.
what is the treatment goal for a pt with SIADH
- restore fluid volume & electrolyte balance
what is considered mild hyponatremia
- > 125 mmol/L
what would be the treatment for a pt with mild hyponatremia with SIADH? what should this cause (2)?
- fluid restriction of 800 - 1000 mL/day
- should result in gradual weight & increase Na
what is considered severe hyponatremia
< 120 mmol/L
what type of IV solution would be given to a pt with severe SIADH? how should it be given & why?
- IV hypertonic saline (3-5%)
- must be infused slowly to prevent fluid overload & to avoid too rapid of a rise in Na
why would a nurse give hypertonic saline to a pt with severe SIADH
- to remove fluid from the cells back into the vascular system so it can be urinated out
what would be the treatment for a pt with severe hyponatremia & SIADH? (4)
- fluid restriction of 500 mL/day
- IV hypertonic saline
- IV Lasix
- Tolvaptan (Samsca)
what is important to monitor with Lasix for a pt with SIADH
- monitor electrolytes carefully (may lose K+ and Na+)
- may need to supplement
what is tolvaptan (Samsca)
- a med that blocks ADH effect on renal tubules = decreased water reabsorption
why is close monitoring required with tolvaptan
- to prevent rapid correction of serum sodium lvl
what position should a pt’s head be in if they have SIADH & why
- HOB flat
- enhance venous return, increase left atrial filling pressure = reduced ADH release
what kind of diet should a pt with SIADH have
- diet high in Na and K
how can we help prevent patients with SIADH from injury (2)? why is this important?
- fluid overload and hyponatremia can cause confusion, changes in LOC, seizures, etc.
actions can include:
- padding the rails
- helping w ambulation
