HELP!!! w/ URGENT MATH QUESTIONS!!

[scorpiogrl]

So I have 2 HUGE tests this week covering medical dosage calculations.... need help with a few questions! PLEASE!!!!

Sorry... these are a bit lengthy...

Order: Demerol 30mg IV administered @ the rate of 2mg/min

(Literature states that Demerol must be diluted to @ least a max. concentration of 15mg/5ml)

Stock: Demerol vial containing 50mg/ml

a. Calculate the total amount of Demerol to be prepared (in mL, round to the nearest tenth)

I got: 30mg x _1mL_ = 0.6mL

50mg

b. Calculate the total time for injection

I got: 30mg x __1min__= 15 min.

2mg

c. Calculate the total amount of diluted drug to be administered

I got: 10ml??????

d. Using a 5cc syringe, calculate the number of seconds per calibration to be administered

I got: HUUUUU????

e. Calculate the amount in mL/min to be administered

Again, I got: HUUUUUU!!!!?????

Order: 400mL of NS with KCl 2mEq/dL to unfuse over 5 hours

Stock: 500ml bag of NS

Vial of KCl labeled 20mEq/5ml

Macrodrop tubing delivering 15gtts/mL

a. Calculate the amount of KCl to be added to the bag

b. Calculate the drip rate

I tried setting this last problem up about 1000 times & just can't seem to work it!!! PLease, any help at all would be greatly appreciated!!!!

[happystudent, RN]

hope this helps......

20meq/5ml::2meq:xml

0.50ml kcl

400cc x 15gtts

---------------------

5 hrs x 60

drop factor 20

should be right....

[mammallamma]

hey scorpio girl!

i just read your posted questions. the first problem you got. the second problem is a bit confusing but here goes. if the order reads 400 ml of ns with 2 meq of kcl per deciliter, then there needs to be a total of 8 meq's of kcl in the bag. if you have on hand 500 ml bag of ns, then you must add 10 meq's of kcl to make it the same strength. it is a ratio problem. 400 is to 500 as 8 is to 10. i am not really sure whether a nurse would empty out 100 ml from the bag and add the correct amount of kcl or whether to only infuse 400 ml of the 500 ml bag. that part i am not sure about. however, if you need to add 10 meq of kcl to the 500 ml bag of ns, then you will add 2.5 ml of the kcl vial. 400 ml/300 min. X 15 gtt/ml = 20 gtt/min.