Learn how to solve heparin drip calculations.
These practice problems for heparin drip calculations will test your ability to calculate:
- new flow rate (mL/hr) based on a PTT
- determining the amount of units needed for a bolus
- units/hr to infuse based on the physician’s order
- how to convert units/kg/hr to determine the amount of Heparin the patient will be receiving based on their weight
To solve these problems, I will be using dimensional analysis. If you are not familiar with how to use dimensional analysis, please check out the other videos in this nursing dosage and calculations series.
When rounding always follow your nursing program or facilities rounding rules! I will be rounding to the nearest tenth for these problems.
Video Lecture on How to Solve Heparin Drip Calculations
Heparin Drips Calculations: How to Solve
Problem 1:
The MD orders your patient to start an IV Heparin drip at 12 units/kg/hr and to administer a loading bolus dose of 60 units/kg IV before initiation of the drip. You’re supplied with a Heparin bag that reads 25,000 units/250 mL. The patient weighs 189 lbs. What is the flow rate you will set the IV pump at (mL/hr)?
First, determine what you are solving for: flow rate (mL/hr)
Second, pick out the correct information you need to solve your problem (watch out for numbers that are distractors). Here is the information you need to solve this problem:
- MD’s order: 12 units/kg/hr
- The bag of Heparin you will be using: 25,000 units/250 mL
- Patient’s weight: 189 lbs
Now, solve:
189 lbs x 1 kg x 12 units/hr x 250 mL = 567,000 = 10.309090 = 10.3 mL/hr
1 2.2 lbs 1 kg 25,000 units 55,000
Answer: 10.3 mL/hr
Problem 2:
Your patient has a Heparin drip running at 24 mL/hr. The Heparin bag reads 12,500 units/250 mL. How many units per hour is the patient receiving?
First, determine what you are solving for: units/hr
Second, pick out the correct information you need to solve your problem (watch out for numbers that are distractors). Here is the information you need to solve this problem:
- Current flow rate: 24 mL/hr
- The bag of Heparin you are using: 12,500 units/250 mL
Now, solve:
24 mL x 12,500 units = 300,000 = 1,200 units/hr
1 hr 250 mL 250
Answer: 1200 units/hr
Problem 3:
Your patient’s recent PTT is 42. According to protocol, you need to increase the Heparin drip by 2 units/kg/hr and administer 30 units/kg IV bolus. You will recheck the PTT in 6 hours. The patient is currently receiving a Heparin drip at 16 units/kg/hr from a bag that reads 25,000 units/250 mL. The patient weighs 163 lbs. How many units will the patient receive as a bolus, and what will you change the flow rate to (mL/hr)?
First, determine what you are solving for: units for this bolus AND NEW flow rate (mL/hr)
Second, pick out the correct information you need to solve your problem (watch out for numbers that are distractors). Here is the information you need to solve this problem:
- Protocol dictates based on PTT to: INCREASE drip by 2 units/kg/hr (current dose is 16 units/kg/hr)
- NEW dose: 18 units/kg/hr
- Bolus needed due to PTT result: 30 units/kg
- The bag of Heparin are using: 25,000 units/250 mL
- Patient’s weight: 163 lbs
Now, solve:
163 lbs x 1 kg = 74.0909 = 74.1 x 30 = 2,223 units
- 2 lbs
Current dose: 16 units/kg/hr….increase by 2 units/kg/hr which will equal 18 units/kg/hr
163 lbs x 1 kg x 18 units/hr x 250 mL = 733,500 = 13.336363 = 13.3 mL/hr
1 2.2 lbs 1 kg 25,000 units 55,000
Answer:
Units for bolus: 2223 units
New flow rate: 13.3 mL/hr
Here are some more Heparin drip practice problems (quiz)