Test 1 Fluid and Electrolyte Disorders Flashcards
Formula for plasma osmolality
[2 x Na+] + [glucose/18] + [BUN/2.8]
sodium content and solution type of 0.9% NaCl
- 154 mEq/L
- isotonic
sodium content and solution type of Lactacted Ringers
- 130 mEq/L
- isotonic
sodium content and solution type of Plasmalyte A
- 140 mEq/L
- isotonic
types of sensible fluid loses
- gastrointestinal
- urine
- skin: sweating
types of insensible fluid loses
- increased respiratory rate
- thermal / chemical burns
- misc: phototherapy, fever
medications that causes SIADH
- amitriptyline
- nortriptyline
- haloperidol
- desmopressin
- carbamazepine
- oxcarbazepine
- cyclophosphamide
- citalopram
- sertraline
medications that causes DI
- Cidofovir
- Lithium
- Amphotericin B
- Demeclocycline
- Foscarnet
- Vasopressin V2-receptor antagonists (conivaptan, tolvaptan)
treatment options for SIADH
- fluid restriction
- correct underlying cause
- 3% NaCl for pts fluid restricted or symptomatic (acute 1st line)
- 0.9% NaCl for pts not fluid restricted or asymptomatic (acute 1st line)
- vasopressin receptor antagonist: conivaptan (acute 2nd line) | tolvaptan (chronic)
- Demeclocycline (chronic only)
treatment options for DI
+ correct free water deficit for pts with severe symptoms (1st line)
+ maintenance medications (2nd line)
- central order of therapy: desmopressin, carbamazepine, indomethacin
- nephrogenic order of therapy: HCTZ, desmopressin, indomethacin or amiloride for lithium-related nephrogenic
other name for SIADH
euvolemic hypotonic hyponatremia
other name for DI
euvolemic hypernatremia
correction formula for Na+
(0.6) (wt in kg) [Target Na+ (120 mEq) - measured Na+] = Total mEq of Na+ to raise sodium concentration to target
What happens with rapid correction of hyponatremia?
Rapid correction of hyponatremia (> 12 mEq/L per day) is associated with the development of osmotic demyelination syndrome from demyelination lesions in the pons
etiologies of hypokalemia
- β2-Receptor Agonists: albuterol, terbutaline
- Diuretics: furosemide, bumetanide, torsemide, HCTZ, chlorothiazide
- Amphotericin B
- Hypomagnesemia
etiologies of hypomagnesemia
- magenesium citrate (increase GI loss)
- diuretics
- amphotericin B
- tacrolimus
- cyclosporine
etiologies of hypocalcemia
- Hypomagnesemia
- loop diuretics
- calcitionin
etiologies of hypophosphatemia
- sucralfate
- Ca2+ carbonate
- sevelamer
- acetazolamide
- insulin
- diabetic ketoacidosis
- alcoholism
etiologies of hyperphosphatemia
- sodium phosphate enemas
- bisphosphonates (i.e., etidronate, pamidronate, zolendronate)
- rhabdomyolysis
treatment options for hyperkalemia
- abnormal EKG -> administer Ca gluconate (peripheral) or CaCl (central)
- give insulin with or without dextrose depending on blood sugar
- consider albuterol
- consider NaCO3
- consider dialysis or exchange resin
- decrease total K stores: kayexalate (chronic)
- non-pharm. pts w/ reanl failure: hemodialysis
- non-pharm. pts w/ normal renal function: loop diuretics
treatment options for hypercalcemia
+ symptomatic:
- kidney failure -> hemodialysis
- normal - moderate kidney function -> 1. NS, 2. loop diuretics, 3. IV calcitonin, 4. IV glucocorticoids
+ asymptomatic:
- Ca2+ < 12 mg/dL: monitor and eliminate underlying cause
- Ca2+ > 12 mg/dL: 1. NS, 2. loop diuretics, 3. IV calcitonin, 4. IV glucocorticoids, 5. biphosphonate
bisphosphonates
block bone resorption; don’t work quickly; reserved for patients with chronic problems
treatment options for hypermagnesemia
- 1st line: antagonize cardiovascular toxicity: calcium gluconate or CaCl
- 2nd line: enhance elimination; normal kidney -> NS bolus and IV loop diuretics; kidney failure -> consider hemodialysis
- eliminate / reduce Mg intake
