# Dosage Calculations - page 10

by minnielynn

265,540 Views | 120 Comments

I am in a desperate situation. I thought I was getting my calculations correctly and today I got back my math results and i got a 70% :crying2: :crying2: :crying2: I am so disappointed I dont know what to do. On my first exam I... Read More

- 0Dec 16, '07 by Foxhello all,

i am currently brushing up on more dosage calculations and i need help on the following problems:

1. order is to give amoxicillin 125mg suspension p.o. every 6 hours. you have available 250mg/5ml of amoxicillin. how many ___ml will you give each dose? how many ___mg/24 hours will this patient receive? i only need the second part.

2. the physician orders 500ml of 5%dw to run 150ml per hours. how many drops per minute should the iv drip (15 gtt/ml set)?

3. order 500ml 20% dw iv are to be infused in 4 hours. the drop factor is 15 gtt = 1ml. how many milliliters per hour will the patient receive?

this is how i solved the problem. 500ml divide by 4 hrs = 125ml/hr (is this right?)

4. the physician orders 1000 ml of lr to run over a 24 hour period. how many microdrops per minute should the iv drip (60 gtt/ml set)

this is how i solved the problem. 1000ml divide by 24 hrs = 42 gtt/per (is this right?)

5. order: 500 ml 5% d/w, with 4 g of mgs04 20% solution. patient to receive 1 g per hour. calculate the infusion rate if the drop factor is 15 gtt = 1 ml. how many ml/hr?

6. order: 50 cc 5% d/w with 1 g ampicillin (omnipen) iv in 20 minutes. calculate the rate of flow in ml/per hour and gtts/ml using 15 gtt/ml?

this is how i solved the problem.

60 min divide by 20 min = 3 min

50ml x 3 min = 150 ml/hr

50ml x 15 gtt/ml divide 20 min = 38 gtt/ min (is this right?)

7. the patient must receive 500 u of heparin iv every hour. if the order is "add 10,000 u of heparin to 1000 ml of 5% d/w." how many drop per minute will the patient receive? drop factor 15 gtt = 1 ml. hint: the patient would be on an iv pump so you would basically sovle for the ml/hr.

8. the iv in progress is 1000 ml of normal saline with 10 meq of kci, and 800 ml remain to be infused. the order is to increase the kci to 40 meq per liter. how many meq of kci will you add to the 800 ml remaining? this might occur in a critical care unit, but unlikely out on a med-surg floor.

9. doctor has ordered heparin infusion of 25,000 units in 500 ml of 5% dw to run at 75 u/min. how many ____units will you be administering per hour? how many ___ ml will you be infusing per hour?

10. physician's order: 500cc 5% d/w with 2 gm of lidocaine iv. how many drops per minute would you administer if the patient must receive 2mg/min? the drop factor is 15 gtt = 1 ml.

11. order 1000cc 5% d/w are to be infused with 10,000 u hepain iv. if the rate of flow 30 gtt/min and the drop factor is 10 gtt = 1 ml, how many milliliters per hour will the patient receive?

12. order 500 ml 5%d/w with 4 g of mgso4 20% solution. patient to receive 1 g per hour. calculate the infusion rate if the drop factor is 15 gtt = 1 ml/hr?

13. the patient must receive 500 u of heparin iv every hour. if the order is "add 10,000 u of heparin to 1000 ml of 5% d/w, how many drops per minute will the patient receive? drop factor 15 gtt = 1 ml.

thanks in advance!!! - 1Dec 16, '07 by
*Daytonite*order is to give amoxicillin 125mg suspension p.o. every 6 hours. you have available 250mg/5ml of amoxicillin. how many ___ml will you give each dose? how many ___mg/24 hours will this patient receive?**125 mg/1**(dose desired)**x 5 ml/250 mg**(dose desired)**=**(amount to give for one dose)__2.5 ml__

if a dose is being given every 6 hours and there are 24 hours in a day then there are 24/6 = 4 doses being given in a 24 hour period. if each dose is 125 mg, then 125 mg x 4 doses =.__500 mg being given/24 hours__

the physician orders 500ml of 5%dw to run 150ml per hours. how many drops per minute should the iv drip (15 gtt/ml set)?**150 ml/1 hour**(amount to give)**x 15 gtts/1 ml**(drip factor)**x 1 hour/60 minutes**(conversion factor)**= 37.5 gtts/minute**, rounded off to__38 gtts/minute__

order 500ml 20% dw iv are to be infused in 4 hours. the drop factor is 15 gtt = 1ml. how many milliliters per hour will the patient receive?

**500 ml/4 hours =**__125 ml/1 hour__

the physician orders 1000 ml of lr to run over a 24 hour period. how many microdrops per minute should the iv drip (60 gtt/ml set)**1000 ml/24 hours**(amount to give)**x 60 gtts/1 ml**(drop factor)**x 1 hours/60 minute**(conversion factor)**= 41.666 gtts/minute**, rounded off to__42 gtts/minute__

order: 500 ml 5% d/w, with 4 g of mgs04 20% solution. patient to receive 1 g per hour. calculate the infusion rate if the drop factor is 15 gtt = 1 ml. how many ml/hr?**500 ml/4 grams**(dose on hand)**x 1 gram/1 hour**(dose desired)**x 15 gtts/1 ml**(drop factor)**x 1 hour/60 minute**(conversion factor)**= 31.25 gtts/minute**, rounded off to__31 gtts/minute__

order: 50 cc 5% d/w with 1 g ampicillin (omnipen) iv in 20 minutes. calculate the rate of flow in ml/per hour and gtts/min using 15 gtt/ml?**50 cc/20 minutes**(dose to give)**x 60 minutes/1 hour**(conversion factor)**=**__150 cc (ml)/hour__

**150 ml/1 hour**(dose to give)**x 15 gtts/1 ml**(drop factor)**x 1 hour/60 minutes**(conversion factor)**= 37.5 gtts/minute**, rounded off to__38 gtts/minute__

the patient must receive 500 u of heparin iv every hour. if the order is "add 10,000 u of heparin to 1000 ml of 5% d/w." how many drops per minute will the patient receive? drop factor 15 gtt = 1 ml. hint: the patient would be on an iv pump so you would basically solve for the ml/hr.**500 units/1 hour**(dose desired)**x 1000 ml/10,000 units**(dose on hand) =(dose to give)__50 ml/hour__

the iv in progress is 1000 ml of normal saline with 10 meq of kci, and 800 ml remain to be infused. the order is to increase the kci to 40 meq per liter. how many meq of kci will you add to the 800 ml remaining? this might occur in a critical care unit, but unlikely out on a med-surg floor.**x**meq/800 ml, solve for**x**= 8 meq of kci

40 meq/1000 ml =**x**meq/800 ml, solve for**x**= 32 meq of kci

you need 32 meq of kci in the current iv to bring the concentration to 40 meq of kci/1000 ml, so**32 meq**(dose desired)**- 8 meq**(dose on hand) =(amount of kci to add to the infusion)__24 meq__

doctor has ordered heparin infusion of 25,000 units in 500 ml of 5% dw to run at 75 u/min. how many ____units will you be administering per hour? how many ___ ml will you be infusing per hour?**75 units/1 minute**(dose being given)**x 60 minutes/1 hour**(conversion factor) =**4500 units/1 hour**

**4500 units/1 hour**(amount being given)**x 500 ml/25,000 units**(dose on hand)**=**(infusion rate)__90 ml/hour__

physician's order: 500cc 5% d/w with 2 gm of lidocaine iv. how many drops per minute would you administer if the patient must receive 2mg/min? the drop factor is 15 gtt = 1 ml.**2 mg/1 minute**(dose desired)**x 500 cc, or ml/2 grams**(dose on hand)**x 1 gram/1000 mg**(conversion factor)**x 15 gtts/1 ml**(drop factor)**= 7.5 gtts/minute**, rounded off to__8 gtts/minute__

order 1000cc 5% d/w are to be infused with 10,000 u heparin iv. if the rate of flow 30 gtt/min and the drop factor is 10 gtt = 1 ml, how many milliliters per hour will the patient receive?**30 gtts/minute**(flow rate)**x 1 ml/10 gtts**(drop factor)**x 60 minutes/1 hour**(conversion factor)**=**(amount being given)__180 ml/hour__

order 500 ml 5%d/w with 4 g of mgso4 20% solution. patient to receive 1 g per hour. calculate the infusion rate if the drop factor is 15 gtt = 1 ml/hr?**1 gram/1 hour**(dose desired)**x 500 ml/4 grams**(dose on hand)**x 1 hour/60 minutes**(conversion factor)**x 15 gtts/1 ml**(drip factor)**= 31.25 gtts/minute**, rounded off to__31 gtts/minute__

the patient must receive 500 u of heparin iv every hour. if the order is "add 10,000 u of heparin to 1000 ml of 5% d/w, how many drops per minute will the patient receive? drop factor 15 gtt = 1 ml.**500 units/hour**(dose desired)**x 1000 ml/10,000 units**(dose on hand)**x 15 gtts/1 ml**(drop factor)**x 1 hour/60 minutes**(conversion factor)**= 12.5 gtts/minute**, rounded off to__13 gtts/minute__Last edit by Daytonite on Dec 16, '07Angie O'Plasty, RN likes this. - 0Jan 12, '08 by Optimistic :>)I understand exactly how you feel I'm currently in my third nursing semester; last semester I did not pass my first dosage calc test, however I ended up Aceing the second one. I know that right now it feels like you just can't do it! But YOU CAN DO IT!!! As you may already be familiar w/the process of nursing school of having to pull it together and continue on. As a matter of fact I was just surfing the web for dosage calc problem to practice (I have an exam in a couple of weeks) all you need to do is type in nursing dosage calculations and a lot of sites will come up, I've found some really helpful sites.

Hang in there, I know you can do this!!! - 0Jan 13, '08 by shauntaebritI hope you guy dont mind but I am practicing for my first exam and I get lost on problems just like these. I like to gather this information and use it to help me to understand how to do IV drips.
- 0Jan 13, '08 by
*Daytonite*Quote from shauntaebrityou will find information and links to websites that have practice problems on how to do iv drip problems on post #6 of this thread in the student forums: http://allnurses.com/forums/f205/any...es-127657.html -i hope you guy dont mind but i am practicing for my first exam and i get lost on problems just like these. i like to gather this information and use it to help me to understand how to do iv drips.**any good iv therapy or nursing procedure web sites** - 0Jan 13, '08 by beth66335Quote from Nrs_angieActually the 5000 isHello

First I have to ask if you wrote the question correctly, because it is unusual to see cc's per minute.... typically IV flow rates will ask drops per minute or mL per hour...

so lets assume its drops (gtt) per minute

use the formula:**DESIRED OVER HAVE ON HAND X QUANTITY**

__800u/hr__X 500 mL = 80 mL/hr

5000 ml

to figure the drops per minute you need to know if you have macrodrop set IV tubing or microdrip set... most institutions use a macrodrip set of 15...

the shortcut method is to use a "DROP FACTOR" which = # gtt in 1 mL

shortcut formula is 60 divided by 15 to give you a drop factor of 4...

mL/hr divided by the drop factor will give you the gtt/min or drops per minute...

**80 mL / Hr divided by 4 = 20 gtt/min**

Now if you recheck the question, and it truely is asking for the cc's per minute...

well there are 60 minutes in an hour...

so divide 80 mL by 60 to = 1.3333

Hope this helps!

Good luck,

Angie__units__of Heparin in the 500ml of D5W,so all you have to do is divide 5000/500 and you get 10u per ml. You need to give 800u in 1 hr which will be in 80ml of solution. So to get cc(ml)/min;

__80ml__X__1hr__=__80__= 1.33cc/min

1hr.... 60min. 60Last edit by beth66335 on Jan 13, '08 - 0Jan 15, '08 by Optimistic :>)I don't mind at all; if there is anything that I can help you with in particular just let me know and I will gladly help you.
- 6Jan 15, '08 by EnviroVegA useful tutorial for learning about and practicing dosage calculations:

http://www.dosagehelp.com/ - 0Jan 16, '08 by Optimistic :>)Quote from EnviroVegThank you for the tip on the dosage calculation tutorial; I have a dosage calc. exam coming up soon; and this website has a lot of useful practice questions.A useful tutorial for learning about and practicing dosage calculations:

http://www.dosagehelp.com/ - 0Jan 24, '08 by cperg510181. A Phsycian orders an IV of D5W to run @ 100mlls

The drop factor is 10gtt/ml

What is the flow rate??

2. Tetracycline is prepared in 50ml of an IV solution it is infusing @ 30gtts/min.

The drop factor of the infusion set is 20gtts/ml. What is the infusion time?/