Math Formulas

Question 1

Amount of medication to

be drawn up in a Syringe:

Answer 1

(Desired amount x Total volume)/

Total amount of drug on hand

Question 2

mL/hour:

Answer 2

(Volume x gtt factor)/

Time (minutes)

Question 3

mg/minute:

Answer 3

(Desired amount x Volume x gtt factor

÷ Total infusion time in minutes)/ Amount of drug on hand

Question 4

mg/hour:

Answer 4

(Desired amount x volume x gtt factor

÷ Total infusion time in minutes)/ Amount of drug on hand

Question 5

Volume/hour:

Answer 5

(Volume x gtt factor)/ Time

Question 6

Drops/minute

Answer 6

(Volume x gtt factor)/ Time

Question 7

Body surface area using cm & kg

Answer 7

(√Height (cm) x weight (kg))/ 3600

Question 8

Body surface area using inches and pounds

Answer 8

(√Height (inches) x Weight (pounds))/ 3131

Question 9

Infusion rate of a drug for a speci

fic body weight per unit of time:

Answer 9

(Concentration of solution (units, mg, mcg, ml))/ Drop rate of set (60 gtml) = (Desired concentration/min x kg body weight)/ (Volume/hour (ml/hr or gtt/min))

Question 10

Preparing a Solution of a Desired Concentration:

Answer 10

(known drug/known volume) = (desired drug/desired volume)