Nurses, I know how confusing Heparin and Coumadin lab monitoring can be. This guide will break them down, explain what they are, and help you understand it all.
This post contains affiliate links
This is informational only, always follow your hospital’s policies and procedures
Nursing Tips for Heparin and Coumadin Lab Monitoring
Something that can be confusing at first is understanding Heparin, Coumadin, and the labs to draw to monitor them appropriately. Let’s go through some basic explanations to have this confusing topic make more sense.
Why Do Nurses Give Heparin and Coumadin Together?
First, let’s understand what they are separately, then you can understand how they work together.
What A Heparin Drip Does
Basically, a Heparin drip quickly thins a patient’s blood to a therapeutic/safe level. These specific numbers depend on why they need their blood to be thin in the first place.
Coumadin is Slower
Coumadin takes longer to kick in and get to a therapeutic level. Some patients are at such high risks for clots that they can’t wait for the Coumadin to kick in, so they need IV Heparin now. Like, right now.
Some Patients Need A Heparin Drip With a Coumadin Bridge
Patients get put on a heparin drip and bridge it to Coumadin for a variety of reasons. Maybe they’re in afib and cannot be converted out of it, maybe they have a brand new mechanical heart valve, maybe they just had a femoral-popliteal bypass and will need their blood thin to maintain patency of the graft. There are many different reasons.
Please check out your nursing school textbook or Nursing.com for more reasons why patients would need these kinds of medications so desperately.
How To Start a Heparin Drip
So you’re taking care of your patient load and see an order to start a Heparin drip pop up. This is one of those stop what you’re doing and do this as soon as possible kind of things.
IV Heparin is Different Than Subcutaneous Heparin
Please keep in mind that IV heparin is different than subcutaneous Heparin. Many patients have received subcutaneous Heparin in the past and assume it’s the same thing and has the same effect. It’s a much higher dose and it goes straight into their circulation.
So if the patient asks you if they can just do those little shots in their belly, you can tell them absolutely and unequivocally no (did you say that in a Professor Slughorn voice? 10 points for Gryffindor if you did).
Setting the IV Heparin Rate
When a patient is on IV heparin, it is started at a set rate based on their weight and how aggressive the medical team would like it to be (again, totally situational) and it is continuously administered through their IV. Occasionally, these order sets contain a weight-based heparin bolus as well. Please double check your orders to make sure to administer the bolus if it is ordered when you’re initiating the drip.
How to Monitor the Safe Levels of the Blood
The way we monitor if the blood is at a safe level is with either a PTT or an Anti-Xa lab. Typically, these are drawn every 6 hours until it is stable (making dosage adjustments based on how high/low their lab is) for a few draws, then it’s drawn every 12 hours, then every day.
Please note, this can vary from facility to facility. Always refer to your policy, procedure, and appropriate order set regarding heparin drip initiation and maintenance.
Example of A Heparin Order
Not sure what a heparin order set is? Check out this example. Do NOT use this example for patient care, it is merely informational.
The patient will then have an order to get Coumadin during the day and an INR will also be ordered daily to monitoring the level of the Coumadin in the blood.
Will giving Coumadin and Heparin together cause them to bleed out?
“Coumadin and Heparin at once?! Isn’t that too much!? They’re going to bleed out!” says the concerned family member.
You can tell them, no, the likelihood of that is very low. The need to thin their blood is much greater than the bleeding risk of the medication at this point. If a patient is being started on Coumadin for the first time, there should be quite a bit of lifestyle education occurring throughout their stay. Many hospitals have specific educational handouts that must be discussed and documented.
Example of A Hospital Educational Booklet about Coumadin
Here’s an example of a hospital educational booklet about Coumadin. Again, do not use this to guide your care, it is simply an example.
Verify Orders to Check INR
If a patient is receiving Coumadin, please make sure there is an order to check their INR (most likely a daily lab, drawn in the morning so the rounding physician will see the result in the morning).
The patient’s doctor will specify a therapeutic range for them, which can be in a nursing order or in one of their notes. It is important for you to know their goal and to communicate them to the patient.
The therapeutic range for their INR again depends on their clinical situation. Patients also respond to Coumadin differently, so the same dose doesn’t work for everyone and the amount of time it takes to get to a therapeutic level varies. This is why they start with a standard dose, check an INR and go from there.
Our goal is to get the INR within that range, near it, or consistently trending up towards it. If the doctor rounds and an INR was not ordered and they weren’t alerted, you’ll probably hear about it.
Heparin and Coumadin Summary
- Heparin = PTT’s or Anti-Xa labs
- Coumadin = INR labs
Are all of these lab draws necessary?
Both labs are completely necessary and non-negotiable. There’s no way around this; the labs must be drawn to know how to correctly dose the medications they so desperately need. Something that is important with these labs is timing, which is why it can be frustrating to patients and family members and turn into a lot of lab draws. We can do our best to combine them, but it doesn’t always work out.
Nurse Pro-Tip: Order Daily Labs at Same Time As INR
If your Heparin drip has been therapeutic and the PTT/Anti-Xa is now a daily lab, order it at the same time as your INR so they don’t have to get stuck twice.
Also, if your PTT/Anti-Xa needs to be drawn around the time some other non-time sensitive labs are due, re-time your labs to be when your PTT/Anti-Xa is due. That’ll save the patient a stick, if possible.
And make sure you tell them you did that so you can get bonus points! Remember though, that PTT/Anti-Xa is TIMED. It cannot be whenever it is easiest.
Even if the patient was just stuck 2 hours ago for another timed lab, you cannot change the time. You run the dangerous risk of their blood being too thick or too thin if you do this and adjusting medications inappropriately.
Why Nurses Prefer Coumadin
Please know that there are many other drugs on the market today to thin the blood appropriately in various situations, however many physicians still prefer Coumadin. Speaking as a nurse managing patients who have had various kinds of blood thinners, I honestly prefer it as well.
The reason is that we know the nature of the beast. We know how to reverse it quickly, how to manage it well and have it down really well. Many of these newer drugs do not have an antidote to reverse it or even a lab to draw to see exactly how much is in the circulation.
When patients or families express frustration about all the lab draws, I educate them about this. While it may be more of a pain and inconvenience, it highly studied and widely used over many years, and nurses and doctors are extremely familiar with all of the ins and outs of it. This usually puts patients and families at ease. Coumadin isn’t perfect for everyone, but it works well for many.
Looking for more practical posts about nursing care? Check out:
- VTE Prophylaxis Explained
- Nursing Tips for Managing New-Onset Atrial Fibrillation
- Practical Patient Education for New-Onset Atrial Fibrillation
Need more in-depth cardiac info? Check out the Cardiac Nurse Crash Course brought to you by FreshRN® where we discuss essential topics like chest tube and arterial line care, cardiac nursing report for the ED/ICU/floor, CABG patient care, in-depth discussion on atrial fibrillation, diagnostics like stress tests and caths, and much more!