common formulas

Percent strength (w/v)

g/100mL

Percent strength (w/w)

g/100g

Percent strength (v/v)

mL/100mL

specific gravity (SG)

g/mL

osmolarity (osmol/L)

[(Wt in g/L)/MW (g/mol)] x # particles x 1000

mEq

(mg x valence)/MW

isotonicity (E)

(58.5 x i) / (MW x 1.8)

mols of molecule

g/MW

mmols of molecule

mg/MW

kcals per g of fat (EN)

9 kcals

kcals per g of protein (EN)

4 kcals

kcals per g of carbs (EN)

4 kcals

kcals per lipid 10% emulsion (PN)

1.1 kcal/mL

kcals per lipid 20% emulsion (PN)

2 kcal/mL

kcals per lipid 30% emulsion (PN)

3 kcal/mL

kcals per dextrose (carbs) (PN)

3.4 kcals

kcals per glycerin (carbs) (PN)

4.3 kcals

kcals per protein (PN)

4 kcals

Nitrogen (g) from protein

g of protein/6.25

corrected Ca (when albumin low)

Ca(sr) + [(4-albumin)x 0.8)]

relative risk (RR)

risk of treatment/risk of placebo

absolute risk reduction (ARR)

(%risk of control)-(%risk of treatment)

Number need to treat/harm (NNT/NNH)

1/ARR [(% risk of control)-(% risk of treatment) represented in decimal]

relative risk reduction (RRR)

[%risk of control group - %risk of treatment group]/(%risk in control group)

hazard ratio (HR)

hazard rate in treatment group / hazard rate in control group

BSA

sq rt ([kg x cm]/3600)

BMI

[lb/in^2] x 730