Help with iv math problem

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Can anyone plz help me with this math problem very confused......thank you..:banghead:

ORDER: diltiazem 125 mg in 100 ml D5W at 10mg/hr IV

AVAILABLE: infusion pump; vial of diltiazem labeled 5 mg/ml

FIND THE RATE AND VTBI:

RATE: ________

VTBI: ________

order: diltiazem 125 mg in 100 ml d5w at 10mg/hr iv

available: infusion pump; vial of diltiazem labeled 5 mg/ml

find the rate and vtbi:

rate: ________

dose desired: 10mg/hour

dose on hand: 5mg/ml
10mg/hour x 1ml/5mg =
1ml/hour
(patient is getting this much of the
diltiazem solution
per hour)

vtbi: ________

10 mg
(dose desired)
/125mg
(dose on hand)
x 100ml
(amount the dose on hand comes in)
=
8 ml
(vtbi--this is what the iv pump will actually be set at)

something confuses me here, if the availible line states you have a vial of diltiazem containing 5mg/ml are they not implying that you are adding x number of ml of this vial to the bag of 100 ml of d5w. in which case it would be 105 ml of fluid to be infused? (5mg/ml= 25mg/5ml) or am i just tired....

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Specializes in med/surg, telemetry, IV therapy, mgmt.
Something confuses me here, if the availible line states you have a vial of Diltiazem containing 5mg/mL are they not implying that you are adding X number of mL of this Vial to the bag of 100 mL of D5W. In which case it would be 105 ml of fluid to be infused? (5mg/ml= 25mg/5mL) or am I just tired....
The problem never mentioned that the vial of 125mg of diltiazem "came in" 5mL of solution. It was only giving the concentration of the diltiazen in solution (5mg/mL) after it had been added.
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So if it's already in the 100ml bag why even mention the vial? Sorry to harp, but I don't get why the info is important to the problem, if the wording is telling you concentration in the vial would that not imply the nurse has to add it? If it is a maximum infusion per mL rate why doesn't it say it that way? I'm still confused...

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Specializes in Critical Care.
So if it's already in the 100ml bag why even mention the vial? Sorry to harp, but I don't get why the info is important to the problem, if the wording is telling you concentration in the vial would that not imply the nurse has to add it? If it is a maximum infusion per mL rate why doesn't it say it that way? I'm still confused...

The information isn't important. Often with these types of questions it is not uncommon to include information that can potentially throw you off. It doesn't matter what the original vial is- it could be 125 grams per milliliter for all we care- either way it got diluted to 125 mg / 100 mL.

This equals a rate of 8 mL / hour in order to infuse 10 mg / hour.

The volume to be infused can't be firmly calculated because the order as written doesn't include a stop time or total dosage (although in practice and according to standards of care, it's typically given for a max of 24 hours).

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Specializes in med/surg, telemetry, IV therapy, mgmt.
so if it's already in the 100ml bag why even mention the vial? sorry to harp, but i don't get why the info is important to the problem, if the wording is telling you concentration in the vial would that not imply the nurse has to add it? if it is a maximum infusion per ml rate why doesn't it say it that way? i'm still confused...

the op posted:

order: diltiazem 125 mg in 100 ml d5w at 10mg/hr iv

available: infusion pump; vial of diltiazem labeled 5 mg/ml

find the rate and vtbi:

rate: ________

vtbi: ________

would it help if two words had been added to the problem like this:

order: diltiazem 125 mg in 100 ml d5w at 10mg/hr iv

available: infusion pump; vial of diltiazem (that is) labeled 5 mg/ml

find the rate and vtbi:

rate: ________

vtbi: ________

the amount of diltiazem (# of mls) in the vial isn't important to the calculations necessary in this problem.

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the op posted:

order: diltiazem 125 mg in 100 ml d5w at 10mg/hr iv

available: infusion pump; vial of diltiazem labeled 5 mg/ml

find the rate and vtbi:

rate: ________

vtbi: ________

would it help if two words had been added to the problem like this:

order: diltiazem 125 mg in 100 ml d5w at 10mg/hr iv

available: infusion pump; vial of diltiazem (that is) labeled 5 mg/ml

find the rate and vtbi:

rate: ________

vtbi: ________

the amount of diltiazem (# of mls) in the vial isn't important to the calculations necessary in this problem.

i will repeat, why is it not applicable? if some one gives me a vial marked 5 mg/ml and wants me to mix 125 mg of that in 100 ml of diluent....it is going to equal 125 ml of liquid in that bag when i mix it.....

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Specializes in med/surg, telemetry, IV therapy, mgmt.
i will repeat, why is it not applicable? if some one gives me a vial marked 5 mg/ml and wants me to mix 125 mg of that in 100 ml of diluent....it is going to equal 125 ml of liquid in that bag when i mix it.....

is that information given in the problem? read the problem carefully. i think you are confusing the labels of mg and ml. the reason that information about the amount the diltiazem comes in is not needed is because it is not necessary to determining the answers that are being asked.

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Is that information given in the problem? Read the problem carefully. I think you are confusing the labels of mg and mL. The reason that information about the amount the diltiazem comes in is not needed is because it is not necessary to determining the answers that are being asked.

dont think so, having never worked icu....maybe this is "just how it is done"

...if i have a vial marked 5mg/ml, which is what is in the problem....for every 5 mg i want to put into that partial fill....i am adding 1 ml of additional liquid.....which would bring the total up to 125

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