MATH HELP! IV- drug and drip question

morte, LPN, LVN · Jan 2, 2009

20mEq/1000 ml : x mEq/60 ml = mEq per hour

same set up for the other two drug

25mg/500 ml : x/21 = hourly rate of drug

IVRUS, BSN, RN · Jan 2, 2009

Regarding help...

Problem #1 = First identify how many hours it would take to infuse the liter bag at 60cc/hr. 1000/60 = 16.66 hours. 20 mEq then will be divided over that time frame giving you 1.2mEq per hr.

Problem #2 = It will take 23.8 hrs for the 500cc NSS with additives to infuse. 25mg/ 23.8 = (A) 1.05mg/hr

Problem #3 = 50mg/23.8 = answer #(B) 2.1 mg/hr

Problem #3 = Each ml will contain 100 units of heparin (25,000/250) To give 1100units an hour, Divide 1100 by 100 giving you answer # (A) 11cc/hr.

:nurse:

Daytonite, BSN, RN · Jan 2, 2009

a patient is admitted to the hospital with intractable bone pain secondary to prostate cancer. the physician orders include:

iv d5w ns with 20 meq kcl/l at 60 ml/hr

iv 500ml ns with 25mg dilaudid and 50 mg thorazine at 21 ml/hr

heparin 25,000 units/250ml d5w, give 1100u/hr

bed rest

do not resuscitate

o2 at 2l/min per nasal cannula

calculate (take your time to understand the question)

how many meq/hr of kcl the patient is receiving?

you must remember to include a conversion factor when calculating this. there are 1000 ml in each liter of fluid. so, each liter of the

d5w ns

actually contains 1000 mls that has the

20 meq kcl

in it. that means that there is 0.02 meq of the kcl in each ml of the solution (20 meq/1000 ml). since the solution is being infused at

60

ml

/hr

, the patient is receiving

0.02 meq of kcl/ml x 60 ml/hour =

1.2 meq kcl/hour

how many mg/hr of dilaudid is the patient receiving?

the same logic applies. you were given infusion rates that involve ml/hour. everything must be calculated in relation to milliliters of that solution. determine how many milligrams of dilaudid are in each milliliter of the iv solution to find out how much is being given at the rate of

21 ml/hr.

with

25mg dilaudid

in

500ml ns

you have (25 mg dilaudid/500 ml ns) 0.05 mg of dilaudid in each ml of ns. since the solution is being infused at

21 ml/hour

, the patient is receiving

0.05 mg of dilaudid/ml x 21 ml/hour =

1.05 mg of the dilaudid/hour

.

how many mg/hr of thorazine is the patient receiving?

determine how many milligrams of thorazine are in each milliliter of the iv solution to find out how much is being given at the rate of

21 ml/hr.

with

50 mg thorazine

in

500ml ns

you have (50 mg thorazine/500 ml ns) 0.1 mg of thorazine in each ml of ns. since the solution is being infused at

21 ml/hour

, the patient is receiving

0.1 mg of thorazine/ml x 21 ml/hour =

2.1 mg of the thorazine/hour

.

the pump is set at _____, so that the patient will receive 1100u/hr

i like to work with the formula

dose desired divided by dose on hand = amount to give

. two of those components have been given to me, so it is a matter of using that information to find the third. i use dimensional analysis (factor labeling) since it is easier and gets the job done efficiently. i am looking to end up with a fraction that is going to give me labels with

ml/hour

. [

your answer choices are given as cc's/hour. cc's are equivalent to mls.

] iv pumps are always set at

ml/hour

. so, my final answer needs to have the label of "ml" in the numerator and "hour" in the denominator. i manipulate my known components to accomplish that.

dose desired

: 1100 units/hour

dose on hand

: 25,000 units/250 ml

250 ml/250 ml

(dose on hand)

x 1100 units/hour

(dose desired)

=

11 ml/hour

or

11 cc/hour

Dianacabana · Jan 3, 2009

How did you know that the volume in the first part of the case study (with the 20 mEq KCl) was 1000 mL? I couldn't find where it said that, which really threw me for a loop when I tried to figure it out.

rawoysteraddict · Jan 3, 2009

I'm a pre-nursing student so please correct me if I'm wrong

"mEq" means "per 1000", so 20 mEq would be 20/1000 of Potrassium Chloride (KCL) per liter or 0.02 per ml.

Daytonite, BSN, RN · Jan 3, 2009

how did you know that the volume in the first part of the case study (with the 20 meq kcl) was 1000 ml? i couldn't find where it said that, which really threw me for a loop when i tried to figure it out.

the problem states: iv d5w ns with 20 meq kcl/l at 60 ml/hr

l is the abbreviation for "liter". one liter is equal to 1000 ml.

Daytonite, BSN, RN · Jan 3, 2009

i'm a pre-nursing student so please correct me if i'm wrong
"meq" means "per 1000", so 20 meq would be 20/1000 of potrassium chloride (kcl) per liter or 0.02 per ml.

that is incorrect. "meq" is the shorthand abbreviation for "milliequivalent". 20 meq/l means that 20 meq of kcl have been added to a liter of the iv solution, d5w ns in this case, and that is all that it means.

Dianacabana · Jan 3, 2009

that is incorrect. "meq" is the shorthand abbreviation for "milliequivalent". 20 meq/l means that 20 meq of kcl have been added to a liter of the iv solution, d5w ns in this case, and that is all that it means.

whooops! missed that extra "l"! out of practice over holiday break.

Old and New · Jan 5, 2009

Here's what I'm coming up with:

1) KCl:

20 mEq/L = 0.02 mEq/ml

0.02 x 60 = mEq/hr

answer: 1.2 mEq/hr

2) Dilaudid:

25 mg/ 500 mL

25 / 500 = mg/mL = 0.05 mg/mL

(21 mL/hr) 0.05 x 21 = mg/hr

answer: 1.05 mg/hr

3) Thorazine:

50 mg/500mL = 0.1 mg/mL

(21 mL/hr) 0.1 x 21 = mg/hr

answer: 2.1 mg/hr

4) Heparin:

25,000 U/250 mL

25,000 / 250 = U/mL = 100 U/mL

(1,100 U/hr) 1,100 / 100 = U/hr

answer: 11 U/mL/hr

Hope this helps.