Calculations and Conversions

Question 1

tsp > mL

Answer 1

1 tsp = 5 mL

Question 2

Tbsp > mL

Answer 2

1 Tbsp = 15 mL

Question 3

oz > mL

Answer 3

1 oz = 30 mL

Question 4

Cup > oz

Answer 4

1 Cup = 8 oz

Question 5

Kg > lbs

Answer 5

1 kg = 2.2 lbs

Question 6

oz > g

Answer 6

1 oz = 28.4 g

Question 7

lbs > g

Answer 7

1 lbs = 454 g

Question 8

inch > cm

Answer 8

1 inch = 2.54 cm

Question 9

grain > mg

Answer 9

1 grain (gr) = 65 mg

Question 10

% )w/v)

Answer 10

X grams / 100mL

Question 11

ratio strength 0.04%

Answer 11

0.04/100 = 1/X X=2500 ratio 1:2500

Question 12

ratio strength 1:4000

Answer 12

1/4000 = X/100 X=0.025%

Question 13

parts per million

Answer 13

g/100mL = X/1,000,000 ex. 30 ppm = 30/1,000,000 = X g/100 mL

Question 14

specific gravity

Answer 14

weight of substance (g) / equal volume of water (mL)

Question 15

dilution and concentration

Answer 15

V1 x C1 = V2 x C2

Question 16

osmolarity

Answer 16

mOsmol/L = weight (g/L) / MW (g/mol) x # particles x 1,000

Question 17

mols

Answer 17

g/MW

Question 18

mmols

Answer 18

mg/MW

Question 19

mEq

Answer 19

(mg x valence charge) / MW

Question 20

BMI

Answer 20

kg/m^2 or lbs/in^2 x 703

Question 21

BMI classifications

Answer 21

<18.5 underweight
18.5-24.9 normal
25-29.9 overweight
30+ obese

Question 22

CrCl

Answer 22

(140-age) x weight kg / (72 x SCr) x0.85 if female

Question 23

IBW

Answer 23

male: 50 + 2.3(inches over 5’)
female: 45.5 + 2.3 (inches over 5’)

Question 24

fluid needs

Answer 24

1,500 mL + (20mL)(kg-20)

generally 30-40 mL/kg/day

Question 25

corrected Calcium

Answer 25

serum Ca + (4 - albumin)(0.8)

Question 26

Anion Gap

Answer 26

AG = Na - Cl - HCO3

normal: 12 or less
high: >12

Question 27

pH calculations

Answer 27

weak acid: pH=pKa + log(salt/acid)

weak base: pH= pKa + log(base/salt)

Question 28

nutritional requirements (dietary intake)

Answer 28

1g protein = 4 kcal
1g carbs = 4 kcal
1g fat = 9 kcal

Question 29

ANC

Answer 29

WBC x [ (%segs + %bands) / 100]

Question 30

Adjusted Body Weight

Answer 30

used if TBW is 1.3xIBW

AdjBW = IBW + 0.4(TBW=IBW)

Question 31

weight to use for CrCl

Answer 31

if TBW < IBW, use TBW

if TBW 1.3xIBW or more, use AdjBW

Question 32

calculating dosing based on renal function

Answer 32

calculate BMI
determine weight for CrCl based on BMI
calculate weight
calculate CrCl

Question 33

nutritional needs (TPN)

Answer 33

dextrose 3.4 kcal/g
glycerol 4.3 kcal/g
IV fat 10%: 1.1 kcal/g
IV fat 20%: 2 kcal/g
IV fat 30%: 3 kcal/g
amino acids: 4 kcal/g

Question 34

basal energy expenditure

Answer 34

15-25 kcal/kg

Question 35

nutrition intake

Answer 35

protein: 1-2g/kg/day
nitrogen: 1g N for every 6.25g protein
nitrogen: g protein intake/6.25

Question 36

Flow Rates

Answer 36

calculate units per mL: 25,000/250mL = 100units/mL

calculate infusion rate: 1,000 units/hr x 1 mL/100 units = 10mL/hr

Question 37

Arterial Blood Gas

Answer 37

pH <7.35 acidosis, pH >7.45 alkalosis
resp. acidosis: elevated pCO2
resp. alkalosis: decreased pCO2
if CO2 and HCO3 are abnomral: compensated
ex. low pH, low CO2, high HCO3 = compensated metabolic acidosis

Question 38

Acid Base Chemistry

Answer 38

acids donate protons, bases accept protons
pH>pKa: more of the acid is ionized
pH=pKa: equal parts ionized
pH

Question 39

Potassium (K)

Answer 39

K is main INTRACELLULAR ion. think Kin

normally: 3.5-5

Question 40

Calcium (Ca)

Answer 40

Ca is main EXTRACELLULAR ion. think: Grandma’s cats are mainly outside
normally: 8.5-10.5

Question 41

Calcium supplements

Answer 41

Ca carbonate: acid-dependent absorption, take with meals - 40% Ca
Ca citrate: independent absorption, w/ or w/o food, 21% Ca
Ca acetate: is a phosphate binder, do not use for Ca replacement

Question 42

Calculating LDL

Answer 42

LDL = TC - HDL - (TG/5)