Calculations ***

Question 1

1 tsp (t) =

Answer 1

5 mL

Question 2

1 tbsp (T) =

Answer 2

15 mL

Question 3

1 fl oz =

Answer 3

30 mL

Question 4

1 cup =

Answer 4

8 oz, 240 mL

Question 5

1 pint =

Answer 5

16 oz, 480 mL

Question 6

1 quart =

Answer 6

2 pints, 960 mL

Question 7

1 gallon =

Answer 7

4 quarts, 3,840 mL

Question 8

1 kg =

Answer 8

2.2 lbs

Question 9

1 oz =

Answer 9

28.4 g

Question 10

1 lb =

Answer 10

454g

Question 11

1 grain (gr) =

Answer 11

65 mg

Question 12

1 inch =

Answer 12

2.54 cm

Question 13

1 meter =

Answer 13

100 cm

Question 14

ratio relationships

Answer 14

4:8 = 4/8 = 1/2

ex: 2:3 = 2 parts + 3 parts = 5 total parts, use ratios to fine out what 1 part is and then multiply by 2 and 3 to find the amount of drug in each ratio segment

Question 15

Order of Operations

Answer 15

B-PEMDAS
-brackets –> parenthesis –> exponents –> multiplication and division –> addition and subtraction

Question 16

corrected phenytoin level formula

Answer 16

(total phenytoin) / (0.2 * albumin) + 0.1

Question 17

Precent Strength *

Answer 17

–> % W/V = g/100 mL (solid mixed into a liquid)

–> % V/V = mL/100 mL (liquid mixed into a liquid)

–> % W/W = g/100 g (solid mixed into a solid

Question 18

Common IV Fluids

Answer 18

–> NA = 0.9% (W/V) NaCl
- 1/2 NS = 0.45% (W/V) NaCl
- 1/4 NS = 0.225 (W/V) NaCl
–> D5W = 5% (W/V) dextrose in water
–> D20W = 20% dextrose in water

Question 19

Ratio Strength

Answer 19

-most multi-step calculations will require converting ratio strength to percentage strength. If a ratio strength is presented in a problem, convert it to a percentage strength and convert it back if needed

-Ratio strength –> percentage strength
% strength = 100/ratio strength

-Percentage strength –> ratio strength
ratio strength = 100/% strength

Question 20

Parts per million

Answer 20

PPM –> Percentage strength
- move the decimal left 4 places

Percentage strength –> PPM
-move the decimal right 4 places

Question 21

Specific gravity

Answer 21

-ratio of the density of a substance to the density of water
–> water has a specific gravity of 1
–> < 1 = lighter than water
–> > 1 = heavier than water

SG = g/mL

Question 22

Dilutions and Concentrations equation

Answer 22

Q1C1 = Q2C2

Question 23

Osmolarity formula

Answer 23

(wt (g/L)/MW (g/mole) * # of particles * 1,000

Question 24

Isotonicity, E value equation

Answer 24

E = (58.5) (i) / (MW of drug)(1.8)

Question 25

once the E value is determined, what are the 3 steps to follow when doing isotonicity problems

Answer 25

1) calculate the total amount of Nacl needed to make the final product/rx isotonic by multiplying 0.9% NS by desired volume of the rx
2) calculate the amount of NaCL represented by the drug. - multiply the total drug amount (in ml or grams) by the E value
3) subtract step 2 from step 1 to determine the total amount of NaCl needed to prepare an isotonic rx

Question 26

moles and millimoles equations

Answer 26

mols: g/MW

mmols: mg/MW

Question 27

Milliequivalents formula

Answer 27

mEq = mg* valence/MW

Question 28

calorie sources in enteral and parenteral admin*

Answer 28

Carbs:
-Enteral: 4 kcal/gram
-Parenteral: 3.4 kcal/gram (glycerol: 4.3)

Fat:
-Enteral: 9 kcal/gram
-Parenteral: product specific ( 10% = 1.1, 20%=2, 30% =3)

Protein:
-Enteral: 4 kcal/gram
-Parenteral: 4 kcal/gram

Question 29

Fluid requirement determination when pt is > 20 kg

Answer 29

fluid requirement = 1500 mL + [(20 mL)(weight in kg - 20)]

Question 30

Determining Caloric needs: BEE and TEE

Answer 30

BEE (males) = 66,37 + 13.75(wt in kg) + 5(ht in cm) - 6.76(age)
BEE (females) = 655.1 + 9.6(wt in kg) + 1.85(ht in cm) - 4.68(age)

TEE= BEE * activity factor * stress factor

Question 31

Protein Requirements

Answer 31

Non-hospitilized/non-stressed: 0.8-1 g/kg/day
Hospitalized/malnourished: 1.2-2 g/kg/day

Question 32

Nitrogen intake formula

Answer 32

= grams of protein / 6.25

Question 33

Non-protein Calories to Nitrogen Ratio

Answer 33

1) calculate the grams of nitrogen supplied per day ( 1 g N = 6.25 g of protein)
2) then divide the total non-protein calories (dextrose + lipids) by the grams of nitrogen

Desirable NPC:N ratios:
- 80:1: the most severely stressed patients
-100:1: severely stressed patients
-150:1: unstressed patients

Question 34

Amino Acid Calculation

Answer 34

protein source = 4 kcal/gram

Question 35

Carbohydrates calculation

Answer 35

Eternal: 4 kcal/gram
Parenteral: 3.4 kcal/gram

Question 36

Fat Calculations

Answer 36

EN: 9 kcal/gram
PN: 10% = 1.1 kcal, 20% = 2 kcal, 30% = 3 kcal

Question 37

Corrected Calcium formula

Answer 37

*calculate when albumin is LOW

= calcium + [(4-albumin)(0.8)]

Question 38

Calcium and phosphate solubility

Answer 38

-choose calcium gluconate over calcium chloride b/c it has a lower risk of precipitation with phosphates
-add phosphate first, after the dextrose and amino acids
—> the calcium and phosphate added together should not exceed 45 meq/L

Question 39

Drug + nutrient interactions with enteral feeding

Answer 39

–> hold feedings 1 hr before and 1-2 hrs after feedings

-Warfarin: enteral products bind to warfarin = dec INR, hold feedings 1 hr before and 1-2 hrs after feedings

-Tetracyclines, quinolones, levothyroxine: will chelate with cations; separate from tube feeds

-Ciprofloxacin: oral suspension is oil based + not compatible; crush IR tabs and mix that way

-Phenytoin: levels are reduced when drug binds to feeding solution, separate from tube feeds by 2 hrs