help with a calculation

Nursing Students Student Assist

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child weighs 9kg

order: dopamine 5mcg/kg/min

dilute 100mg in 200ml of d51/4 NS @ 6.75ml/hr

dose= 2-5mcg/kg/min

drug available dopamine 400 mg/5ml

will the dilution orders yield the correct concentration????????

9kg....x...5mcg/kg...=...45mcg

................1min...........1min..

100mg...x.....5ml....=...1.25ml

.................400mg

6.75ml...x...100mg........x...1hr.......x..1000mcg...=...56mcg

...1hr...........201.25ml........60min..........1mg...............1min

no, that would yield an overdose.

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

child weighs 9kg

order: dopamine 5mcg/kg/min

dilute 100mg in 200ml of d51/4 ns @ 6.75ml/hr

dose= 2-5mcg/kg/min

drug available dopamine 400 mg/5ml

will the dilution orders yield the correct concentration??????

dopamine: 100mg/400mg x 5ml = 1.25 ml needed to add to 200ml of d51/4 ns. this gives you a dose on hand of 100 mg of dopamine in 201.25 ml of d51/4ns.

order: dopamine 5mcg/kg/min = 5mcg/9 kg/min = 45 mcg/minute

order: infusion rate of 6.75ml/hr

will the dilution orders yield the correct concentration??????
or rewriting the question,
is 100 mg of dopamine in 201.25 ml of d51/4ns infusing at 6.75 ml/hour = 45 mcg/minute?

6.75 ml/hour
(dose being given)
x 1 hour/60 minute
(conversion factor)
x 100 mg/201.25 ml
(dose on hand)
x 1000 mcg/1 mg
(conversion factor) =
55.9006 mcg/minute
round off to
56 mcg/minute
(dose being given in mcg per minute). go back to the question. . .
is 100 mg of dopamine in 201.25 ml of d51/4ns infusing at 6.75 ml/hour = 45 mcg/minute
? and substitute the answer.
. .is 56 mcg/minute = 45 mcg/minute?

analysis: 56 mcg/minute is 11 mcg/minute more than ordered. in fact, it is double the dose! so,
no
, the dilution orders will
not
yield the correct concentration.

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