FLUID BALANCE- final

Question 1

renal causes of hypovolemia

Answer 1

RENAL
- diuretics
- osmotic diuresis
- hypoaldosterone state
- salt wasting (lose excessive salt in urine)
- diabetes insipidus

Question 2

hypovolemia associated clinical manifestations

Answer 2

• related to dec CO
• redistributional causes—> hypoalbuminemia, capillary leakage
• sepsis

Question 3

hypovolemia
- dx

Answer 3

full hx, physical
LABS:
BUN:creatinine ratio

• normal 10:1 pre renal azotemia >20:1
• urinary Na+ conc <20
• urine osmo >450
• specific gravity 1.015

Question 4

hypernatremia- renal loss of water
- drug induced v. osmotic

Answer 4

drug induced
- loop diuretics: isoosmotic diuresis, impaired concentrating ability of nephrons

osmotic
- mannitol, urea, glucose: impaired water reabsorp due to organic solutes in tubular lumen, water loss surpasses conc. ability
- these solutes draw water out

Question 5

hypernatremia tx

Answer 5

tx underlying and correct water deficit

• correct water deficit over 48-72 hrs
• plasma Na dec limit to 0.5 per hr or 12 mmol/L per 24 hrs

Question 6

Effect on renal potassium balance
- aldosterone
- hyperkalemia
- distal urinary flow
- hypokalemia

Answer 6

• aldosterone: inc secretion
• hyperkalemia: inc secretion
• distal urinary flow: enhance excretion
• hypokalemia: reabsorption inc

Question 7

hyperkalemia- etiology/causes of potassium SHIFT

Answer 7

• rhabdomyolysis, hemolysis, burns, strenous exercise, sepsis
• hypertonicity (K follows the flow)
• insulin deficiency
• Metabolic acidosis
• pharmaceuticals (digoxin, B agonists, succinylcholine, arginine)

Question 8

hyperkalemia
- etiology/causes of DEC EXCRETION

Answer 8

• renal failure, intertstitial nephritis, sickle cell ds
• hypoaldosteronism (type IV RTA, diabetic nephropathy, heparin, end stage AIDS, adrenal insuff)
• pharmaceuticals (ACEi, trimethoprim, NSAIDs, spirinolactone, triamterene, pentamadine)

Question 9

hypokalemia
- etiology of renal potassium loss

Answer 9

• inc aldosterone effect (hypoaldosteronism, renovascular HTN, cushings, licorice, congenital anomaly/ 11beta or 17 alpha hydroxylase def.)
• inc flow at distal nephron (diuretics like furosemide or thiazides)
• hypomagnesemia
• renal tubular acidosis (fanconi syndrome, interstitial nephritis, metabolic alk)
• genetic d/o (bartter’s, liddle’s)

magnesium, calcium, and potassium usually follow each other!!!!