FEN

Question 1

formula for osmolality

Answer 1

2*Na + BUN/2.8 + glucose/18

Question 2

normal osmolality

Answer 2

265-285

Question 3

Winter’s formula

Answer 3

pCO2 = (1.5*HCO3 + 8) +/- 2

Question 4

distal RTA

Answer 4

aka type I/classic
distal tubule can’t secrete H+ into urine
urine with high pH

mimicked by spironolactone

Question 5

proximal RTA

Answer 5

aka type 2
proximal tubule can’t reabsorb bicarb
urine still acidic

mimicked by acetazolamide

Question 6

type 4 RTA

Answer 6

aldosterone resistance/deficiency

hyperkalemia

Question 7

daily sodium requirement

Answer 7

3 mEq/kg/day

higher in preterm infants

Question 8

nephrogenic DI

Answer 8

X linked

resistance to vasopressin

Question 9

low urine sodium

Answer 9

< 10-20

Question 10

drugs that cause SIADH

Answer 10

vincristine, cyclophosphamide, carbamazepine

Question 11

tx of SIADH

Answer 11

fluid restriction
lasix and hypertonic saline
demeclocycline (if 8yo+)

Question 12

causes fo pseudohyponatremia

Answer 12

hyperTG

elevated proteins

Question 13

daily potassium requirement

Answer 13

2 mEq/kg/day

Question 14

signs of 5% dehydration

Answer 14

tachycardia, decreased tears, decreased UOP

needs 50 mL/kg

Question 15

signs of 10% dehydration

Answer 15

sunken eyes, poor skin turgor, sunken fontanelle

needs 100 mL/kg

Question 16

signs of 15% dehydration

Answer 16

shock, delayed cap refill

needs 100 mL/kg

Question 17

sodium content of ORS

Answer 17

75 mEq/L of sodium

Question 18

how to calculate sodium deficit

Answer 18

(goal - measured) * weight * 0.6

Question 19

electrolyte disturbance in CF

Answer 19

hypochloremic hyponatremic metabolic alkalosis

Question 20

max amount to correct sodium in hypernatremia

Answer 20

10-12 mEq/L per day