Matters of the Heart - Pulmonary Embolism
Our Matters of the Heart series has covered heart-related topics so you may be wondering why we have switched to respiratory. The truth is, although the lungs are a part of a different bodily-function tribe, they are one of the two places that the blood is pumped to. The lungs vasculature is particularly close to the heart, and if there is a back up in the lungs vessels, guess what is going to be majorly affected?
You already guessed it, I know, because you are an awesome human, so it makes it a little less exciting to throw confetti when I shout, “THE HEART!” but… THE HEART!
Now that we have that out of the way, let's talk Pulmonary Embolisms!
What is a Pulmonary Embolism (PE)?
Pulmonary Embolism (AKA PE) is a blood clot that has lodged in the lungs vasculature, usually a major artery. A patient may have multiple PEs or even bilateral PE’s. A pulmonary embolism can potentially be life-threatening, and many go undiagnosed, only to be later found on the patient's autopsy.
Yup, it can often be a reason someone died and nobody caught it or knew about it… Terrifying, I know.
Anyway, these clots are formed outside the lung, usually in one of the extremities, and has traveled to the lung where it has lodged. Clots are considered severe if they occlude greater than 50% of the artery. This occlusion causes a back-up of blood flow, giving the patient pulmonary hypertension and decreases the amount of oxygen the blood is able to obtain for distribution. Basically, the body goes into a state of hypoxia and heart failure.
Speaking of pulmonary hypertension...
What is Pulmonary Hypertension?
Pulmonary Hypertension is high pressure in the pulmonary arteries leading to a backup of blood in the right ventricle.
Pulmonary Hypertension does not have any early signs or symptoms so a patient may have it and not know it. It is usually found because a patient starts to have signs or symptoms that can’t be explained otherwise.
So the signs and symptoms of pulmonary hypertension are similar to those of a heart attack, asthma exacerbation or panic attack. If all other things are ruled out they may perform a cardiac catheterization to measure pressure in the pulmonary arteries for diagnosis.
A patient may have pulmonary hypertension for a multitude of reasons and one of those reasons is a pulmonary embolism. Generally speaking, if you treat the PE, pulmonary hypertension will resolve itself. If it doesn’t, the patient will likely be placed on a lifelong medication regimen.
So the goal is to prevent pulmonary embolisms, and if it was not prevented, then to make sure to catch it before it causes pulmonary hypertension.
What can cause Pulmonary Embolisms?
It is actually kind of scary how easily our body can form clots and I will never forget the 24-year-old patient I had who had a stroke… at 24… caught way too late and she had irreversible brain damage. Did I say she was 24 year old..??? YOU GUYS! This can happen to anyone! Age doesn’t discriminate here. We have to be thinking about what puts people at risk for blood clots in order to prevent them or quickly catch one BEFORE it is too late.
To help you remember the risk factors, think about Virchow’s Triad:
This is when your blood is pooling in any area of the body, so think about those patients who are bedridden, obese (think limited mobility), heart failure (if the bloods not moving then its pooling). When the blood is swirling about in circles and bumping into itself, it tends to reach out for a friend to hold onto and just like that, you have a scared little cluster of cells holding onto each other for dear life.
The cells that line the heart and blood vessels are endothelial cells and damage to them causes them to become angry and inflamed. This makes the blood pressure go up because there is less room inside the blood vessels to dilate. When the blood pressure goes up, the risk of breaking off some of that artery bacon grease increases and BOOM, you have a floating chunk of fat to lodge into a small space such as an arteriole in your lung. Injury to the endothelial layer can be from trauma, infection, burns, surgery, etc.
This is when the body is in a state of producing more than what is necessarily normal. For example, the body’s response to COPD is to produce more RBCs to have an increase in the blood oxygen carrying capacity (Polycythemia). Other situations where the body would act differently include postpartum, intake of estrogen (like when used as a contraceptive), or malignancy to name a few.
What are the signs and symptoms of a Pulmonary Embolism (PE)?
This is a difficult thing to answer because, sometimes, PE don’t have any signs or symptoms. If signs and symptoms are present, they can mimic other pathologies, such as heart attack or an anxiety attack But if a patient presents to you with any of the following, be thinking of the possibility that it could be a PE:
Shortness of breath with tachycardia
Sudden onset of pleuritic chest pain
Pleural friction rub upon auscultation
New onset of atrial fibrillation
What testing do you do to diagnose a PE?
The first step is to draw blood and get results in two major things:
D-Dimer: This is released when the body is trying to break down a large clot, the higher the results, the bigger the clot.
BUN/Creatinine: If a CT-PE is to be performed you need to know if their kidneys are performing well enough to be able to handle the contrast dye they inject into the IV.
Did I say two? Well, the truth is the biggest two you are going to be looking at are listed above but I really want to add number three that says, look at all your results to paint a picture of the patient and don’t just zone in on two results. So look at the coag panel, troponins, complete blood count, metabolic panel, etc. too. Remember: PEs often masquerade as another condition so don’t forget to look for those conditions too. The patient may be having a heart attack and not a PE but if you are looking at the D-Dimer only… You get my point.
AAANNDDD on that point… while you are waiting for results, get an EKG and a Chest X-Ray to eliminate heart attack or something obvious like a pneumothorax.
If the D-Dimer comes back high and the kidneys are behaving, you will send the patient to get a CT-PE. It should be noted that you could use an MRI to get these results too, and I am sure there is some certain indication for this, but really, it’s one of those tests that are much too much if you know what I mean.
What treatments are used for Pulmonary Embolisms (PEs)?
If your patient has a PE, give them oxygen because their little lungs are likely struggle-bussing to meet the O2 requirements of the body.
Then grab a calculator and some heparin and start busting up some clots!
This is weight based. You first make sure their weight is in Kilograms, then you multiply by the ordered amount of units/hour. For a PE or a DVT it is usually between 12-18 units. You will also likely give the patient a bolus of heparin to jump-start their clot-busting action. The bolus is also weight based. The most important part of starting heparin is to MAKE SURE YOU ARE GIVING THE PROPER DOSE…
That is like super flipping important. You will accomplish this by asking another nurse to double check your calculations, orders and pump settings.
The other thing to note about heparin drip therapy is that every 6 hours you will be drawing your patients blood to check coagulation levels and to see if you are therapeutic. When the results of the PTT/PT or Anti-Xa are available, you will then follow a nomogram that tells you to either increase, decrease, or hold the heparin drip based on the results.
And guess what? You want to have another nurse check your work on this too.
TPA- In the event that the patient meets all the criteria and it is indicated, TPA may be used. This is also weight based but will be calculated out by the doctor and the pharmacist.
What are the nursing considerations for patients with PEs?
You will want to monitor the patient's vital signs frequently, especially the heart rate and pulse ox. Every nurse will practice differently, however, I assess neuro more frequently just in case the clot (or another clot) floats to the brain and lodges somewhere. I also prefer to have patients that are getting heparin therapy to be on the cardiac monitor, at least during the beginning, to monitor for clots meandering to the cardiac arteries.
Lastly, heparin is a blood thinner… I make all my patients getting heparin fall risks and slap a big ole fall precautions sign on their door with a yellow wristband and socks on the patient. Then I have a talk with the patient about the rules of being my patient. Rule number 1: no falling, rule number 2: no dying. Because let's be real here, if a patient falls and hits their...anything… while on heparin they are at risk of bleeding big time so let's just prevent that, shall we?
This post was written by Susan DuPont BSN, RN, CEN of bossrn.com who likes to hunt, fish, play euchre and practice survival skills.
Disclaimer: This material should be used to supplement your understanding of the cardiovascular system. Any use of the information given in this post series is at your own risk and should be verified prior to making it a part of your nursing practice. There may be affiliate links associated with some products but we promise that we will never recommend anything that we don’t use ourselves.