CALCULATIONS
PRACTICE
EXAM
A client with cardiogenic shock weighs 220 lb and
is receiving dopamine at the rate of 3
mcg/kg/minute. The solution strength available is
dopamine 400 mg in 250 ml of D5W. The nurse
should set the infusion pump to deliver how many
ml/hours? (Enter numeric value only. If rounding is
required, round to the nearest tenth.) -
√Answer>11.3
First, convert pounds to kg, 220 lb : X = 2.2 lb : 1
kg = 100 kg. Next, calculate the dosage per
minute, 3 mcg/kg/min x 100 kg = 300 mcg/min.
Convert mcg/min to mcg/hour, 300 mcg/min x 60
min=18,000 mcg/hour. Convert mcg/hr to mg/hour,
18,000 mcg/hr = 18.0 mg/hour. Calculate the rate,
400 mg : 250 ml = 18 mg : X ml 400X = 4500 X =
11.25 = 11.3 ml. So, 18 mg/11.3 ml should be
infused at 11.3 ml/hour.
,>Quiz: A client with hypertension who weighs 72.4
kg is receiving an infusion of nitroprusside (Nitride)
50 mg in D5W 250 ml at 75 ml/hour. How many
mcg/kg/minutes is the client receiving? (Enter
numeric value only. If rounding is required, round
to the nearest tenth.) - √Answer>3.5
Calculate the mg/hour infusing, 50 mg : 250 ml =
X : 75 ml 250X = 3750 and X = 15 mg/hour. Next,
convert mg/hr to mcg/hour, 15 mg/hour = 1 mg /
1000 mcg = 15,000 mcg/hour, then divide by 60
min = 250 mcg/minute. Lastly, 250 mcg/72.4
kg/min = 3.45 = 3.5 mcg/kg/minute.
>Quiz: A client who weighs 70 kg is receiving a
dopamine solution of 800 mg/500 ml normal saline
at 5 ml/hour. How many mcg/kg/minutes is the
client receiving? (Enter numeric value only. If
rounding is required, round to the nearest tenth.) -
√Answer>1.9
To change ml/hour to mcg/kg/minute, use the
formula: desired rate (5 ml/hour) / volume
available (500 ml) x dose available (800 mg) = 8
mg/hour. Next, convert milligrams/hour to
mcg/kg/minute: mg (8) x 1000 / kg (70) / 60
minutes = 1.904 = 1.9 mcg/kg/minute.
,>Quiz: A client is receiving an IV solution of
sodium chloride 0.9% (Normal Saline) 250 ml with
amiodarone (Cardamone) 1 gram at 17 ml/hour.
How many mg/minutes of amiodarone is infusing?
(Enter numeric value only. If rounding is required,
round to the nearest tenth.) - √Answer>Convert
grams to mg, 1 gram equals 1,000 mg. Using ratio
and proportion - 1,000 mg : 250 ml :: X mg : 1ml
250X= 1,000 so X = 4 mg/ml is the solution
concentration of amiodarone. The infusion rate
(ml/hour) x concentration (mg/ml) divided by 60
minutes/hour 17 ml/hour x 4 mg/ml = 68/60 = 1.13
= 1.1 mg/minute.
>Quiz: A client who weighs 176 pounds is
receiving an IV infusion with esmolol hydrochloride
(Brevibloc) at 48 ml/hour. The IV solution is
labelled with the concentration of Brevibloc 10
mg/ml. How many mcg/kg/minutes is the client
receiving? (Enter numeric value only.) -
√Answer>100
Convert pounds to kg by dividing 176 pounds by
2.2 pounds = 80 kg. Convert the IV concentration
from mg to mcg. 1 mg : 1000 mcg :: 10 mg :
10,000 mcg. Infusion rate (48 ml/hour) x
concentration (10,000 mcg/ml) divided by 60
minutes/hour x 80 kg = 48 x 10,000 divided by 60
x 80 = 480, = 100 mcg/kg/minute.
, >Quiz: The nurse is preparing the change-of-shift
report for a client who has a 265 ml secondary
infusion that was started 2 hours ago at a rate of
85 ml/hour via an infusion pump. The nurse should
report that how many ml remain to be infused by
the on-coming nurse? (Enter numeric value only.)
- √Answer>95
85 ml x 2 hours = 170 ml has infused. 265 ml (total
amount to be infused) - 170 ml (amount infused) =
95 ml remain to be infused.
>Quiz: A male client receives a prescription for
ondansetron hydrochloride (Zofran) 4 mg IV to
prevent postoperative nausea after an inguinal
hernia repair. The medication is available in 2
mg/ml. How many ml should the nurse administer?
(Enter numeric value only.) - √Answer>2
Use ratio and proportion, 4 mg : X ml = 2 mg : 1 ml
2X = 4 X = 2
>Quiz: The nurse is preparing to administer
Hepatitis B Vaccine, Recombinant (Energex-B) 5
mcg IM to a school-aged child. The vaccine is
labelled, 10 mcg/ml. How many ml should the
nurse administer? (Enter numeric value only. If
rounding is required, round to the nearest tenth). -
√Answer>1 or 0.5