CRITICAL CARE CALCULATIONS (100%)
#1 The order reads to give 3 mcg/kg/min of Dopamine. The patient weights 100 kg.
In order to give the Dopamine you first need to know how it is supplied by pharmacy. In this situation
you will have 400mg Dopamine in 250 mL D5W. (If you are working on the floor and the Dopamine is
already running you would check the bag that is running to see how it was supplied.)
You will use the same formula you use to calculate your other drug dosages. That formula is
Desired (dose to be given) x volume (how much it is supplied in)
Have (dosage available)
In this situation to figure out the dose to be given (desired), you would multiply 3 mcg x 100kg x 60 min.
(If you don’t multiply by 60 min at this time you would need to multiply your answer later by sixty since
you will probably be placing an amount into the IV pump which is usually in mL/hr )
To plug in the amounts you would have:
18,000 mcg x 250mL
400 mg
Since you have mcg on the top and mg on the bottom you would need to convert one of the two so that
you have the same units on the top and bottom. In this situation I will change the mcg to mg.
18 mg x 250mL
400 mg
Your answer is 11.2, therefore, the pump would be set at 11mL/hr.
, #2 Your go into the patient’s room and the patient has Dopamine running at 15 mL per hour. The amount of
Dopamine (15 mL) does not really tell you anything except the amount of fluid the patient is receiving.
You have no idea how much medication the patient is getting, therefore, you need to convert this to
mcg/kg/min. When you look at the bag you note Dopamine 400mg in 250mL D5W.
To solve this problem you use the same formula as above;
Desired x Volume
Have
The only difference is you plug in the volumes where you would have plugged in the dosage and your
volume becomes the dosage of drug that is supplied.
15mL/hr x 400 mg
250mL
The answer is 24 mg per hour.
You know need to change that to mcg and divide that number by the patient’s weight in kg and by 60
minutes to get the answer into mcg/kg/min
In this problem that would be
24mg times 1000mcg = 24,000 mcg
24,000 mcg divided by 100 kg divided by 60 minutes
Your answer is 4 mcg/kg/min
CRITICAL CARE MATH PRACTICE Questions/Answers
1. Mr. P. is ordered a dopamine drip at 3mcg/kg/min. Mr. P. weighs 80kg. Your dopamine is supplied in
the concentration of 800mg in 250mL D5W. The IV should be run at _________ mL/hr.
2. Mrs. B. is ordered epinephrine at 3.4mcg/min. It is supplied at 2mg in 500mL D5W. The IV should be
started at _________ mL/hr.
3. Mr. C. was ordered nitroglycerin (NTG) at 67mcg/min. The drug is supplied at 100mg in 250mL D5W.
The IV should be started at _______ mL/hr.
4. Your patient was transferred from another hospital. On arrival you note he is on Dopamine at 10mL/hr.
Hanging is Dopamine 400mg in 250mL D5W. How many mcg/kg/min is your patient receiving? Your
patient weighs 60kg.
5. Your patient is ordered to be started on heparin 1100units/hr. The drug is mixed in a concentration of
25,000 units heparin in 250mL D5W. How many mL/hr should your patient receive? How many
microdrops per minute?
6. Your patient is on Dopamine to increase his blood pressure. The order reads Dopamine to maintain
#1 The order reads to give 3 mcg/kg/min of Dopamine. The patient weights 100 kg.
In order to give the Dopamine you first need to know how it is supplied by pharmacy. In this situation
you will have 400mg Dopamine in 250 mL D5W. (If you are working on the floor and the Dopamine is
already running you would check the bag that is running to see how it was supplied.)
You will use the same formula you use to calculate your other drug dosages. That formula is
Desired (dose to be given) x volume (how much it is supplied in)
Have (dosage available)
In this situation to figure out the dose to be given (desired), you would multiply 3 mcg x 100kg x 60 min.
(If you don’t multiply by 60 min at this time you would need to multiply your answer later by sixty since
you will probably be placing an amount into the IV pump which is usually in mL/hr )
To plug in the amounts you would have:
18,000 mcg x 250mL
400 mg
Since you have mcg on the top and mg on the bottom you would need to convert one of the two so that
you have the same units on the top and bottom. In this situation I will change the mcg to mg.
18 mg x 250mL
400 mg
Your answer is 11.2, therefore, the pump would be set at 11mL/hr.
, #2 Your go into the patient’s room and the patient has Dopamine running at 15 mL per hour. The amount of
Dopamine (15 mL) does not really tell you anything except the amount of fluid the patient is receiving.
You have no idea how much medication the patient is getting, therefore, you need to convert this to
mcg/kg/min. When you look at the bag you note Dopamine 400mg in 250mL D5W.
To solve this problem you use the same formula as above;
Desired x Volume
Have
The only difference is you plug in the volumes where you would have plugged in the dosage and your
volume becomes the dosage of drug that is supplied.
15mL/hr x 400 mg
250mL
The answer is 24 mg per hour.
You know need to change that to mcg and divide that number by the patient’s weight in kg and by 60
minutes to get the answer into mcg/kg/min
In this problem that would be
24mg times 1000mcg = 24,000 mcg
24,000 mcg divided by 100 kg divided by 60 minutes
Your answer is 4 mcg/kg/min
CRITICAL CARE MATH PRACTICE Questions/Answers
1. Mr. P. is ordered a dopamine drip at 3mcg/kg/min. Mr. P. weighs 80kg. Your dopamine is supplied in
the concentration of 800mg in 250mL D5W. The IV should be run at _________ mL/hr.
2. Mrs. B. is ordered epinephrine at 3.4mcg/min. It is supplied at 2mg in 500mL D5W. The IV should be
started at _________ mL/hr.
3. Mr. C. was ordered nitroglycerin (NTG) at 67mcg/min. The drug is supplied at 100mg in 250mL D5W.
The IV should be started at _______ mL/hr.
4. Your patient was transferred from another hospital. On arrival you note he is on Dopamine at 10mL/hr.
Hanging is Dopamine 400mg in 250mL D5W. How many mcg/kg/min is your patient receiving? Your
patient weighs 60kg.
5. Your patient is ordered to be started on heparin 1100units/hr. The drug is mixed in a concentration of
25,000 units heparin in 250mL D5W. How many mL/hr should your patient receive? How many
microdrops per minute?
6. Your patient is on Dopamine to increase his blood pressure. The order reads Dopamine to maintain
