Calculations
Drug Reconstitution Dosage Conversion
There are several formulas used to calculate drug doges: Only one formula is necessary to calculate any medication. Choose the formula
easiest for you to Use..
A
Desired Dose Dose on Hand
x
Volume of Drug
on Hand
Volume of Desired
Dose (X) ,
B.
Dose on Hand
Volume on Hand
desired Volume Desired (X)
"
CDesired Dose
Dose on Hand
Practice Questions: Answers on page 25.
. .
1. Concentration of Lanoxin is 50 mcg/0.5 cc. How many cc's would be
administered to give 75 mcg Lanoxin?
2.Final concentration of diluted Penicillin is 300,000 units/10 cc
The dose is Penicillin 400,000 units IV. How many cc's would you give?
3. Lasix comes 10 mg/lcc. The order is for 22 mg, how many cc's would you
administer?
4. The Ampicillin final concentration is 250 mg/5 cc. What volume do you give for
a dose of 400 mg IV?
16
5.
Gentamicin is available in the concentration of 40 mg/1 cc. How many cc's do you need to give 6 mg.dose?
6.
From an ampule labeled codeine 15 mg/0.5 cc, give 4 mg. How many cc's do you need?
7.
Compazine vial is 25 mg/2cc concentration. How many cc’s do you give for a dose of 12.5 mg?
"
8.
Heparin is available in the concentration of 6,000 U/0.3 cc’s. The physician order is for 10,000 units. How many cc's do you give?
9. Chloramphenicol is available in final diluted concentration of 250 mg/5 cc.
The physician order is for 125 mg. How many cc’s do you give?
10.Phenobarbital is available as 130 mg/cc. The physician order is 270 mg. How
many cc's do you give? .
11.The physician order is for 1.2 mg of Atropine and the vial is 10mg/cc’s. How
many cc's would you administer?'
12. An Aminophylline bolus of 70 mg. is ordered. and the Aminophylline
concenuation available is 25 mg/cc. How many cc's would 'you prepare?
13.A chi1d has an order for 2 mg. Valium IV prior to an invasive procedure. The
vial of Valium is 5 mg . How many cc's would you administer?
14. Vancomycin 150 mg. is ordered for a child and' the reconstituted volume is 500
mg/10 cc. How many cc’s would you administer?
17
.'
. ....
____A n_
..
15.Tobramycin 30 mg is ordered and the vial is 40 mg/cc. How many cc's would
you administer?
'16. Narcan 0.1 mg is ordered for Ii' child in the emergency room and the vial is 20
mcg. How many cc's would you administer?
. .
17.Vistaril 1.5 mg. is being given postoperatively and the vial is 25 mg/cc. How
many cc's would you administer?
18. Solu-Medrol 24 mg. is being given; the vial is 40 mg/cc. How many cc's would
you administer?.
19. Demerol 15 mg is being given as a one time' pre-procedural drug 'and the vial is'
25 mg/cc. How many cc’s would you administer?
20. Cefataxime 300 mg. is ordered and you have reconstituted one gram of cefotaxime with 9.8 cc of sterile Water yielding a concentration of 1 gram/10 cc. How many cc's will you administer?
18
CALCUlATIONS
Medication Dosage Based on Bodv Weight/Dose Medication Dosage Based on Bodv Weight/ Dav
The nurse must also chcc’sk if the ordered dosage is within a safe range for the child. This can be calculated on a drug range' given/day or a drug range given/dose. First determine the pediatric dosage range/kilogram of medication .from the Drug Reference
I .
I.
b.
Drug range given/day.
a. Utilize highest dosage identified and multiply times child's weight in
)kilograms. This will give you the maximum 24 hour dosage.
Utilize lowest dosage identified and multiply times child's weight in kilograms to give you the minimal therapeutic range.
To identify single dose quantity; divide the 24 hour total dosage by the number of doses to be given during one 24 hour period ( if dose given every 12 hours, divide by 2; if very 6 hours by divide by 4)
c.
. .."
Example: Ampicillin safe dosage range is 100-400 mg/kg/24 hours. a. How much is maximum 24 hour dose for a 10 kilogram chi1d?
400x 10 =4000 or 4 grams per day maximum.
b.How much is maximum if given every 4 hours ( 6 doses/24---
hours) .
4000/6 = 666 mg Q 4 hours
n. Drug range given/dose
a. Utilize highest dosage identified and multiply times child's weight. The dose given should be equal to or below this amount per dose.
Practice questions: Answers on page 25.
Gentamicin safe dose is 5.0 to 7.5 mg/kg/24 hours. How much would the maximum safe dose be for an 8 kg child if Gentamicin was given every 8 hours?
'.
2. Usual dose of Demerol is 1-2 mg/kg/dose pm. What would the maximum dose
for a 15 kg. child be for Demerol?
3. AminophylIine usual dose is 4-6 mg/kg/dose every six hours. What is the
maximum dose for a 4 kg infant for one dose?
19
4. Lasix usual dose is 1-6 mg/kg/dose. Usmg 2 mg/kg every 12 hours, how much is
needed for a 12 kg child for one dose?
5. Cefotaxime dose for children is 100-200 mg/kg/day q 6-8 hours. What is the maximum daily amount of Cefotaxime for a 44 kg child? What is the maximum dose if given Q 8 hours?
6. Decaadron is being given for airway edema. The dosage is 0.25 -0.5 mg/kg/dose.
What is the maximum dose for a 18 kilogram child?
7.Reglan is being given to increase stomach emptying. The range for infants is
0.05 - 0.1 mg/kg/dose. What is the maximum and minimum dose for a 6 kg.
infant ?
8. Phenobarbital is being given for Status Epilepticus ~Dosing 5-10 mg/kg/dose. What
is the maximum dose for a 34 kg. child?
9. Albumin is being given as a volume expander at 1.0 gm/kg/dose. What is the
correct dose for a 15 kg. child?
10.Ampicillin is ordered for a child. The safe range is 100 - 400 mg/kg/day Q 4-6
hours. What is the maximum daily dose for a 25 kg. child? What is the dose
Q 6 hours?..'
11. Chloramphenicol is being given to? an 8 kg infant using. 100 mg/kg/day Q 6 hours.
What is the daily maximum dose? What is the dose Q 6 hours?
12. A dose of Valium is ordered for a 12 kg. toddler a muscle relaxant at
0.3 mg/kg/dose. What is the maximum dose that should be given? .
13.Atropine is ordered during a bradycardic episode for a 8 kg. infant. The correct
dose is 0.02 mg/kg/dose. What is the correct dose for this baby?
14. Cimetidine is ordercd for a 36 kg. child using the range of 20-40 mg/kg/day Q 6 hours. What is the maximum daily dose for this child? What is the maximum dose' if given Q 12 hours?
.. 20
. .
....-....
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Answers to Practice Questions
1.0.75 a::
2.13.3 a::
3.2.2 a::
4.8.0 a::
5.0.15 a::
6.0.13 a:
7.1.0 a:
8.0.5 a::
9.2.5 a::
10.2.1 cc:
11.1.2 .
12.2.8 a:
13.0.4 cc:
14.3.0 a:
I5.0.75 cc:
16.5 cz:
.17.0"06 a:
18.0.6' a:
19.0.6 a:
20.3.0 a:
1. . 20 mg Q8h
2..30 mg.
3.24 mg
4.24 mg
5.a. 8.8 smns
b. 2.9 grams
6:-9 mg
7.Q.3 minimum
0.6 IDmmum
8.340 mg .
9.15 pams
10.a. 10 gnmslday
b. 2.5 Q6h
11.a. 800 mg/day
b. 200 ml q6h
12.3.6 ml
13.0.16 mg
14.a. 1.44 ~msI~y
b. 720 mg q 1211