Help with calculations OB

Nursing Students Student Assist

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Calculate dose given and compare to safe dose ... normal dose is 2.5 mg/ kg/ dose q 8 hr.

Newborn weight: 3600 gm. Order is 9 mg Gentamycin iv q 12.

How do I do this? Also, what would be the nursing intervention after doing this calculation?

I don`t get how to do this.. is gm supposed to mean gram here? Then the normal dose would be 3600000x2.5 mg which makes no sense... Any help would be greatly appreciated.

Thanks.

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first you must convert grams to kilograms. so instead of multiplying times 1000 divide by 1000

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so.. 2.5/3.6== 0.69 mg every 8 hrs-- which is 0.08 per hr. since the order is 9 mg every 12 hours 9/12= 0.75 mg per hour so it`s too big of a dose? im not sure I did this right still...

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Hmm yea what is a gm?

If that does mean grams...then the baby weighs 3.6kg.

2.5mg X 3.6kg= 9 mg...q8hrs means 3 doses per day so the baby could get 27mg a day -and that would be safe.

If the order is 9mg q12hrs then the baby would be getting 18mg a day....its a low dose, and they may say its below the therapuetic range, but yes it is safe to give.

I think I did that right...:rolleyes:

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Specializes in Emergency.

Los Gatos did do it right. Though just because it's below the maximum doesn't mean it's safe if it's this far out of the range. Many would consider a margin of +/-10% as safe.

Especially since it's Gentamyacin, if it's too weak to kill the bugs, the bacteria will just build a resistance. If you consider encouraging superbugs as safe, then by all means.... ;)

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Thanks so much, don`t know why i was dividing. lol. It makes more sense now

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