Heparin Math.....HELP

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

Up Vote Up Vote ×
Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.

Show me what you did so we can figure out what you are doing wrong

Up Vote Up Vote ×
Specializes in Pedi.

Ok, first step- how much heparin do you administer for the bolus dose. Your patient weights 187 lbs- what is that in kg? Then you need to administer 80 u/kg- so what is your dose? From there, you can figure out how much to administer in mL.

For the second step, you have 25,000 units of heparin in 500 mL. So what is your concentration? You need to administer 20 u/kg/hr so what is your dose in units/hr? From there, you can figure out your rate in mL/hr.

Up Vote Up Vote ×
Specializes in Emergency.

This thread is an example of nursing math we do every day in the er. Pharmacy actually does the math and tells you the dose & rate but you better believe that we double check those calculations.

Up Vote Up Vote ×

The bolus will be 7 mL

Infusion will be 32 mL/hr on your pump.

Up Vote Up Vote ×

Aw, that takes away her the opportunity to show her own math, because now she has the answer and we'll never know where she messed up so we can't help her fix it. OP, figure out these things first:

187 lbs = ?? kg

25,000 units in 500cc = ?? units/cc

Now do you see what you need to do to figure out how many cc/hour you need for those 20 units per kg?

Up Vote Up Vote ×
Aw, that takes away her the opportunity to show her own math
I presume that any quiz requires the student to show their work so providing the answers without any of the steps simply lets her/him figure out for him/herself if s/he's done it correctly.

I didn't show any math, I just provided answers.

And as I proved conclusively a couple of threads ago, my answers aren't to be blindly trusted.

Up Vote Up Vote ×

To figure out bolus:

187 lbs divide by 2.2=85 kg which rounds to 90 kg.

Then you take 90 x 80=7200

7200 divided by 1000u=7.2 ml

To figure out drip:

90 x 20=1800

1800 divided by 25000=0.072

0.072 x 500ml=36ml/hr

Up Vote Up Vote ×
Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
The bolus will be 7 mL

Infusion will be 32 mL/hr on your pump.

I think you meant this on the other math question
Up Vote Up Vote ×
Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
To figure out bolus:

187 lbs divide by 2.2=85 kg which rounds to 90 kg.

Then you take 90 x 80=7200

7200 divided by 1000u=7.2 ml

To figure out drip:

90 x 20=1800

1800 divided by 25000=0.072

0.072 x 500ml=36ml/hr

That was very nice of you.

However allnurses requires students to show their work first so we can help them see where they are going wrong. We strive to make student the best nurse they can be. This is a vital part of nursing and it is imperative the students understand this.

Up Vote Up Vote ×
Specializes in Pedi.
To figure out bolus:

187 lbs divide by 2.2=85 kg which rounds to 90 kg.

Then you take 90 x 80=7200

7200 divided by 1000u=7.2 ml

To figure out drip:

90 x 20=1800

1800 divided by 25000=0.072

0.072 x 500ml=36ml/hr

You don't round 85 kg to 90 kg for this problem. Since when do you round weight to the nearest 10th for calculating doses?

The correct bolus dose for the patient who weighs 85 kg is 6800 units whereas the correct bolus dose for a patient who weighs 90 kg is 7200 units. So you've just bolused your patient with an extra 400 units of heparin because you rounded his weight.

Same thing for the drip. 20 u/kg/hr for an 85 kg person is 1700 units/hr but for a 90 kg person it's 1800 units/hr. In the course of 24 hrs, you'd be giving this patient an extra 2400 units of heparin plus the extra 400 units you gave him for the bolus. That has med error/incident report written all over it....

Up Vote Up Vote ×

Ok first lemme just say I was only trying to help so really there is no need to be mean. Second, I was only showing them how I was shown. I'm still in nursing school due to graduate in December so I'm not a new nursing school student just to clear that up. Third this was how I was shown so don't shoot the messenger. I get my math right on my tests all the time! Guess I should have not been so nice to try to help!

Up Vote Up Vote ×
+ Join the Discussion