Please Help: BSA drug calculation

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Can you tell me if this is correct? Thank you for your reply.

A doctor orders Gantrisin syrup 3g/m squared for a child whose body surface is 0.6 m squared. The solution available is 0.5g/5ml. Calculate the number of ml to administer.

3000 mg/500 mg x 5 ml = 30 ml

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Specializes in med/surg, telemetry, IV therapy, mgmt.

i believe the answer is 18 ml. you didn't account for the childs' bsa. based on the dimensional analysis approach, the set up equation would be:

3 gram/1 square meter
x
5 ml/0.5 gram
x
.6 square meters/1

cancelling out labels and simplifying, you get:

3/1
x
.6/1
x
5 ml/0.5

doing the math, you get:

(3 x .6 x 5ml)/0.5
=
18 ml

here are a couple more links for you on pediatric dosage calculations:

http://www.delmar.edu/nsci/jartman/1406-peds.htm -

http://www.lww.com/promos1/karch/images/05-karch.pdf - page 7 gives an example of how to work a problem using a child's bsa

http://pharmcal.tripod.com/ch4.htm#areadose - this is an online pediatric drug calculator. just pick the dosage formula you wish to use, input the information asked, click the "calculate" button and you will be given the correct answer.

i have classes myself all day today, so i can't get back online until late tonight unless i have time to get into a computer lab today.

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important, though, to eyeball the actual question before you even start with the calculations, so you have a ballpark guess of how much it ought to be.

for example, if the order is 3gm for each meter squared, and the kid is 0.6 meter squared, then you know you are gonna need less than 3gm. six-tenths of that, actually, which is 1.8gm, right?

so if your solution is 0.5gm in 5cc, you need to know many 0.5gm are there in 1.8gm? that would be 3.6 of them.

so, 3.6 x 5cc is 18cc.

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