Calculations

Question 1

How do you calculate mOsmol/L?

Answer 1

mOsmol/L = wt(g/L)/MW(g/mol) * #particles * 1000

Question 2

How do you calculate specific gravity?

Answer 2

SG=wt(g) / vol(mL)

Question 3

How many mLs in 1 pint?

Answer 3

473 mLs

Question 4

How many pints are in 1 quart?

Answer 4

2 pints = 1 quart

Question 5

How do you calculate CrCl? (Cockcroft-Gualt)

Answer 5

eCrCl = (140 - age) / (72 * Scr) * wt (* 0.85 if F)

Question 6

How do you calculate ideal body wt?

Answer 6

IBW(M) = 50kg + (2.3kg)(inches over 60)
IBW(F) = 45.5kg+(2.3kg)(inches over 60)

Question 7

How do you calculate adjusted body wt?

Answer 7

AdjBW = IBW + 0.4(TBW - IBW)

Question 8

How do you decide which body wt to use to calculate eCrCl?

Answer 8

Under wt(BMI use actual BW
Normal wt(BMI 18.5-24.9) -> use IBW
Over wt/obese (BMI 25+) -> use AdjBW

Question 9

How do you calculate BMI?

Answer 9

BMI = wt(kg) / ht^2(m)

For lbs/in^2 use correction * 704.5

Question 10

What are the 4 BMI classifications and their corresponding BMI ranges?

Answer 10

Under wt 30

Question 11

What is percent strength?

Answer 11

x% (w/v) = x(gm) / 100(mL)
x% (w/w) = x(gm) / 100(gm)
x% (v/v) = x(mL) / 100(mL)

Question 12

What is the conversion ratio of aminophylline to theophylline?

Answer 12

0.8 : 1

Question 13

How many mg are in 1 grain?

Answer 13

~ 65

Question 14

What is PPM?

Answer 14

Parts per million

PPM = x(gm) / 1,000,000 mL

Question 15

How do you determine if someone is dehydrated from the labs?

Answer 15

BUN : SCr > 20 = dehydrated

Question 16

Rough estimate of Basal energy expenditure?

Answer 16

20 kcal/kg/day

Question 17

What is the ratio of nitrogen to amino acid?

Answer 17

1(gm) : 6.25(gm)

Question 18

How many kcal are in 1(gm) of carbs?

Answer 18

4 kcal

Question 19

How many kcal are in 1(gm) of dextrose?

Answer 19

3.4 kcal

Question 20

How many kcal are in 1(gm) of protien?

Answer 20

4 kcal

Question 21

How many kcal are in 1(gm) of fats?

Answer 21

9 kcal

Question 22

How many kcal are in 1(mL) of (10/20/30%) IV fluid emulsion?

Answer 22

10% = 1.1 kcal
20% = 2 kcal
30% = 3 kcal

Question 23

How much fluids should a person receive per day?

Answer 23

30-40(mL/kg)

Question 24

How many pints in 1 gallon?

Answer 24

8 pints = 1 gallon

Question 25

What is the protein requirement for a normal or stressed person?

Answer 25

Normal = 0.8-1(gm/kg/day)
Stressed = 1.2-2(gm/kg/day)

Question 26

What is the max rate for dextrose?

Answer 26

4(mg/kg/min) or

7(gm/kg/day)

Question 27

What is a normal range for K?

Answer 27

3.5-5 (mEq/L)

Question 28

When should you correct Ca?

Answer 28

If albumin is

Question 29

How do you correct for Ca if albumin is

Answer 29

Ca(corrected) = Ca + [(4 - alb) * 0.8]

Question 30

What binds to Ca and can form precipitates in an IV?

Answer 30

Phosphate

Question 31

How can you minimize the risk of calcium and phosphate precipitating?

Answer 31

Add PO3 first
Use Ca gluconate when possible
Ca & PO3 NTE 45(mEq/L)
Refrigerate

Question 32

What size filter should be used on lipid emulsions?

Answer 32

1.2 micron

Question 33

How do you calculate mols?

Answer 33

Mol = gm / MW

Question 34

How do you calculate mmol?

Answer 34

Mmol = mg / MW

Question 35

How do you calculate NaCl equivalent or E value?

Answer 35

E value = (58.5 * i) / (MW * 1.8)

i = ionization factor (1, 1.8, 2.6, 3.4, 4.2)

Question 36

How do you calculate mEq?

Answer 36

mEq = (mg * val) / MW  -or- 
mEq = mmol * val

val = charge on particle of interest (not # of particles)

Question 37

How do you convert C into F?

Answer 37

F = (C * 1.8) + 32

Question 38

How do you calculate ANC?

Answer 38

ANC = WBC * (%seg + %band) / 100

Question 39

How do you calculate the minimum weighable quantity of a scale?

Answer 39

MWQ = sensitivity requirement / % error acceptable