Heparin Math.....HELP

Nursing Students Student Assist

Published

Heparin Therapy: Math

The health care provider prescribes the following:

  • Administer IV bolus dose of heparin 80 Units per kilogram of body weight.
  • Initiate IV infusion of 500 ml of 5% Dextrose in water with 25,000 Units of heparin at a rate of 20 Units of heparin per kilogram of body weight per hour.

The heparin bolus is available in a 1,000 Unit/ml concentration. Mrs. Adams weighs 187 pounds.

At what rate should the IV pump be set to deliver the prescribed rate of infusion? (Enter numerical value only. If rounding necessary, round to the whole number.)

I have worked this problem several times, and clearly have no idea what I am doing..PLEASE help

And, just to let my inner geek roam for a bit...

Whenever you're rounding - anything - don't think about the absolute change, the percentage change:

For example, rounding 5-to-10, 105-to-110, and 995-to-1000 are all absolute changes of 5 but percentage changes of

100%, 5%, and 0.5% respectively...

The former is a gross error, the middle may or may not be acceptable depending on circumstance, and the latter is generally negligible (unless you're considering the odds that plane will crash at each take-off, for example, or that the wrong limb will be amputated)

0 Votes
Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
Ok!!!!
I apologize for not checking the math earlier. I usually do. My kids were on the run this morning.

I know you get your tests correct. That is a good thing. In the real world you do not round up prior to the conversion. The difference between 85 lbs/38.6 or 37kg is very different from 90lbs/40.9 kg or 41kg. The bolus difference is for 37kg a bolus of 2960units of heparin and for 41kg 3280units of heparin....a difference of 320units of heparin.

IN weight based dosage in a high risk med is a HUGE difference. IN the pediatric population it can be fatal.

I would double check with your instructors to be sure. I know we are correct but you need to believe it for yourself.

0 Votes
And, just to let my inner geek roam for a bit...

Whenever you're rounding - anything - don't think about the absolute change, the percentage change:

For example, rounding 5-to-10, 105-to-110, and 995-to-1000 are all absolute changes of 5 but percentage changes of

100%, 5%, and 0.5% respectively...

The former is a gross error, the middle may or may not be acceptable depending on circumstance, and the latter is generally negligible (unless you're considering the odds that plane will crash at each take-off, for example, or that the wrong limb will be amputated)

From a fellow math geek...very cool!

0 Votes

Thank you for your help every one! I had the bolus....but had absolutely no clue how to even start the second part of the problem. It was for a case study that I did before we learned how to do heparin drips in class.

0 Votes

Ahh I love this site. I haven't started nursing school yet and I've learned a lot just reading the posts!!! You people are great. I hope to one day be as great a nurse as you all are. It's pretty obvious the great teachers and nurses that comment on these threads. Thanks again and looking forward to posting one of many questions on here!!! Lol

0 Votes

You don't round 85 kg to 90 kg, because now you just added 11 pounds to your patient. FYI

0 Votes

I know this is an old topic and the OP's math homework has long ago been turned in and/or math test taken But back to the original math: Someone said the bolus will be 7mL. I agree (80(u)x85(kg)= 6800/1000=6.8 mL, rounded to 7mL.

But the infusion question, someone said the answer is 32 mL and I'm not getting that.

85(kg)x20(u)= 1700u/hr

there are 50u/ of heparin per mL in this bag

1700/50= 34

So 34 mL/ hr. Isn't this the right answer? Not trying to prove anyone wrong, I just have a very similar math problem and I want to make sure I am doing it right. Thanks!

0 Votes

But the infusion question, someone said the answer is 32 mL and I'm not getting that.

85(kg)x20(u)= 1700u/hr

there are 50u/ of heparin per mL in this bag

1700/50= 34

So 34 mL/ hr. Isn't this the right answer? Not trying to prove anyone wrong, I just have a very similar math problem and I want to make sure I am doing it right. Thanks!

That's correct. If there are 50 units in one cc, how many cc's make 1700 units? 34cc is correct.

0 Votes
+ Add a Comment