Dosage Calculations!!!

Hello,

I'm a first year adult nursing student in s. of England. Would really appreciate any help with these questions (trying to complete my drug calculations booklet!!).

1) PATIENT PRESCRIBED SOLUBLE INSULIN 100 UNITS IN 5O ML 0.9% SODIUM CHLORIDE SET AT AN INFUSION RATE OF 6MLS PER HOUR. HOW MANY UNITS OF INSULIN WILL PATIENT RECEIVE EACH HOUR- CALCULATE FLOW RATE AS ML/HR.

2)PATIENT PRESCRIBED 40,000 UNITS OF HEPARIN OVER 24 HOURS. THE VIAL OF HEPARIN IS 25000 UNITS/ML AND YOU'RE ASKED TO DILUTE THE HEPARIN IN NaCl 0.9% TO RUN AT 1ML/HR. a) what volume of heparin do you draw up?

b) how much sodium chloride do you add to the heparin to infuse 40,000 units over 24 hours?

3) PATIENT PRESCRIBED 60mmol K+ IN 500MLS NaCl TO BE GIVEN OVER 3HOURS. HOW MANY mmol OF K+ WILL PATIENT RECEIVE EACH HOUR?

Thanks for taking time to read this.

I am so glad i dont have to do this any more.. I would be there for hours!!

break it down.. 100units of insulin in 50mls is 10 units in 5mls or 2 units a ml.. so will be 12 units in 6mls.. I think!!

the rest.. I'd need a calulator for .. or maybe not to have a couple of glasses of wine with sunday dinner!!

someone else help!!

Karen

Hello,

I'm a first year adult nursing student in s. of England. Would really appreciate any help with these questions (trying to complete my drug calculations booklet!!).

1) PATIENT PRESCRIBED SOLUBLE INSULIN 100 UNITS IN 5O ML 0.9% SODIUM CHLORIDE SET AT AN INFUSION RATE OF 6MLS PER HOUR. HOW MANY UNITS OF INSULIN WILL PATIENT RECEIVE EACH HOUR- CALCULATE FLOW RATE AS ML/HR.

2)PATIENT PRESCRIBED 40,000 UNITS OF HEPARIN OVER 24 HOURS. THE VIAL OF HEPARIN IS 25000 UNITS/ML AND YOU'RE ASKED TO DILUTE THE HEPARIN IN NaCl 0.9% TO RUN AT 1ML/HR. a) what volume of heparin do you draw up?

b) how much sodium chloride do you add to the heparin to infuse 40,000 units over 24 hours?

3) PATIENT PRESCRIBED 60mmol K+ IN 500MLS NaCl TO BE GIVEN OVER 3HOURS. HOW MANY mmol OF K+ WILL PATIENT RECEIVE EACH HOUR?

Thanks for taking time to read this.

2a= 1.6ml

do you know my brain has died, will have to play about with this and get back to you. Have not done this for a couple of years got to get the grey cells working again

60mmols in 3 hours, how much an hour????????????????????????????

Hello,

I'm a first year adult nursing student in s. of England. Would really appreciate any help with these questions (trying to complete my drug calculations booklet!!).

1) PATIENT PRESCRIBED SOLUBLE INSULIN 100 UNITS IN 5O ML 0.9% SODIUM CHLORIDE SET AT AN INFUSION RATE OF 6MLS PER HOUR. HOW MANY UNITS OF INSULIN WILL PATIENT RECEIVE EACH HOUR- CALCULATE FLOW RATE AS ML/HR.

2)PATIENT PRESCRIBED 40,000 UNITS OF HEPARIN OVER 24 HOURS. THE VIAL OF HEPARIN IS 25000 UNITS/ML AND YOU'RE ASKED TO DILUTE THE HEPARIN IN NaCl 0.9% TO RUN AT 1ML/HR. a) what volume of heparin do you draw up?

b) how much sodium chloride do you add to the heparin to infuse 40,000 units over 24 hours?

3) PATIENT PRESCRIBED 60mmol K+ IN 500MLS NaCl TO BE GIVEN OVER 3HOURS. HOW MANY mmol OF K+ WILL PATIENT RECEIVE EACH HOUR?

Thanks for taking time to read this.

OI

do your own homework

:lol2:

Hello,

I'm a first year adult nursing student in s. of England. Would really appreciate any help with these questions (trying to complete my drug calculations booklet!!).

1) PATIENT PRESCRIBED SOLUBLE INSULIN 100 UNITS IN 5O ML 0.9% SODIUM CHLORIDE SET AT AN INFUSION RATE OF 6MLS PER HOUR. HOW MANY UNITS OF INSULIN WILL PATIENT RECEIVE EACH HOUR- CALCULATE FLOW RATE AS ML/HR.

2)PATIENT PRESCRIBED 40,000 UNITS OF HEPARIN OVER 24 HOURS. THE VIAL OF HEPARIN IS 25000 UNITS/ML AND YOU'RE ASKED TO DILUTE THE HEPARIN IN NaCl 0.9% TO RUN AT 1ML/HR. a) what volume of heparin do you draw up?

b) how much sodium chloride do you add to the heparin to infuse 40,000 units over 24 hours?

3) PATIENT PRESCRIBED 60mmol K+ IN 500MLS NaCl TO BE GIVEN OVER 3HOURS. HOW MANY mmol OF K+ WILL PATIENT RECEIVE EACH HOUR?

Thanks for taking time to read this.

1) 100 units/50 ml = 2units/ml

6ml x 2units/ml = 12units/ml

I have never come across 100units in 50ml. It is always a 1:1 ratio, 50 units of insulin in 50 mls of normal saline.

2a) 40,000/25000 x 1ml = 1.6ml

2b) im am not so sure about the answer. i have an answer but i need to re-think if its really correct.

3)60mmols/3 hours = 20mmols/hour

hope this helps. if you have the answer in 2b. please post it, i would like to know how you derive it.

1ml an hour over 24 hrs is 24ml, then take away the 1.6ml heparin. Walla!!!!

1ml an hour over 24 hrs is 24ml, then take away the 1.6ml heparin. Walla!!!!

this is also the answer i have calculated. i know in clinical setting there is a protocol for heparin infusion. wooh....., need to ask the pharmacist or daytonite, they are really good, when it comes to calculations.

All I can say is thank gawd for the pharmacy. All our IV meds are prepared down there.

There are several set formulae for drug calculations. The most well known being:

what you want/what you've got x what it's in

You can use that for most med calculations (including fnding the answer to 2a.) There are also formulae for calculating IV infusion volumes and rates, which I'm sure your uni must have told you. E.G

mls p hr = volume/time in hrs

You can find plenty of helpful websites on dosage calculations for nurses too. GO check them out. Once you know your formulae then applying them is easy & you'll find tackling calc questions a doddle.

I have to say that once on the ward you very, very rarely use them though - that's why it's tough to be a student:lol2:

About the only one I use now, & that's only very infrequently, is the what u want one!

Hello,

I'm a first year adult nursing student in s. of England. Would really appreciate any help with these questions (trying to complete my drug calculations booklet!!).

1) PATIENT PRESCRIBED SOLUBLE INSULIN 100 UNITS IN 5O ML 0.9% SODIUM CHLORIDE SET AT AN INFUSION RATE OF 6MLS PER HOUR. HOW MANY UNITS OF INSULIN WILL PATIENT RECEIVE EACH HOUR- CALCULATE FLOW RATE AS ML/HR.

2)PATIENT PRESCRIBED 40,000 UNITS OF HEPARIN OVER 24 HOURS. THE VIAL OF HEPARIN IS 25000 UNITS/ML AND YOU'RE ASKED TO DILUTE THE HEPARIN IN NaCl 0.9% TO RUN AT 1ML/HR. a) what volume of heparin do you draw up?

b) how much sodium chloride do you add to the heparin to infuse 40,000 units over 24 hours?

3) PATIENT PRESCRIBED 60mmol K+ IN 500MLS NaCl TO BE GIVEN OVER 3HOURS. HOW MANY mmol OF K+ WILL PATIENT RECEIVE EACH HOUR?

Thanks for taking time to read this.

Hello,

I don't know if this is right but this is what I got for your questions:

1) 100U/50ml so I did 100U divided by 50ml and that gave me 2u/ml and then I said 6ml/hr times 2U/ml, so the ml cancelled out then 6 times 2 gave me "12U/hr". So the patient is receiving 12u of insulin each hour as long as the pump is set for 6ml/hr.

2) I am not for sure about this one. The only thing I could figure out is in order to give 40,000U and the vial of heparin is 25,000U/ml then in order to get 40,000U: you would need to say 40,000U divided by 25,000U times 1ml and that will give you "1.6ml" that is what you will need to draw from the vial to get 40,000U of heparin. Then mixing that with NaCl 0.9%. I thought that had to be given to you. I was not for sure what to do once I got the 40,000U in my syringe. Sorry:o

3) The way that I figured this was: 60mmol K+ divided by 500ml = 0.12 mmol K+ per 1ml. Then I did 500ml divided by 3hrs= 166.66667ml/hr. Once I got that then I could get mmol K+ per hour by taking the 0.12mmol K+ per 1ml times the 166.66667ml per hr and that = "20mmol K+ per hr the patient will receive".

I can recommend 2 formulars from an NCLEX preparation book, the always do work!

1) D:HxQ=X

D= doctor's order

H=dose on hand (from drug label)

Q=quantitiy (for ex. ml)

X= how many tablets to give or ml/hour

2) V:Txdrop factor=gtt/min

V=volume in ml = doctor's order

T=time in minutes

drop factor= depends on drop set used