My family member was diagnosed with a PE. What does that mean?

PE generally stands for pulmonary embolism, one of the regular emergent conditions we are on the look out for in the ER. They can be life threatening.

Let’s first start with a quick review of the pulmonary system. The pulmonary system is how our body gets oxygen from the atmosphere to our blood system while simultaneously removing carbon dioxide from our cells to the outside environment. The main structure involved in this action are, you guessed it, the ever-present lungs.

Our lungs have two basic parts. There is the air part ( to simplify things) and the blood part. The first involves air passing into our mouth, nose, trachea and bronchioles, ending in microscopic sacs called, alveoli.

The second part of the lungs involve the vessels coming from our body, branching into ever smaller vessels ending up infinitely close to these alveoli. Alveoli are where the action is.

When we inhale, oxygen comes into these sacs, due to laws of physics, it is able to pass over into the small vessels coming into close contact with these alveoli. The exact opposite happens when carbon dioxide leaves the blood to go back into the air. That’s when we exhale.
So, we need two basic parts to work for us to breathe successfully.

If this does not happen we can begin to feel short of breath or, in the worst case, stop breathing all together. Usually when we think of someone having trouble breathing we think of not being able to get enough air to the lungs. However, one can have just as much trouble breathing if we can’t get enough blood to the lungs. This is exactly what happens when someone has a PE.

A PE is a blood clot that has lodged in the blood vessels that are bringing oxygen from and carbon dioxide to the lungs. If the clot is in a small vessel that “serves” only a small part of the lungs then the symptoms will usually be mild. On the other hand, if the clot blocks the main pulmonary artery, called a saddle embolus, the the symptoms can be quite severe, in some cases resulting in immediate death before the patient can seek any medical care.
So what are the symptoms and what can we do?

PE can be difficult to diagnose only because its symptoms can be similar to other critical diagnoses. One of the most common symptoms is that the patient will have trouble breathing. This seems obvious.

Now, add to it another common symptom with PE such as having chest pain and we are starting to sound a lot like an MI (heart attack). CT of the chest is the gold standard to diagnose PE although there are other less intrusive tests that can guide your physician as to the likelihood of these symptoms being the result of a PE.

Now that we know we have a PE what to do?

For years the mainstay of treatment has been blood thinners such as heparin or Coumadin. While these make sense and are still widely used, they don’t cure the current clot. Mainly they help prevent any further clot formation.

Recently, it has become standard of care to use lytics such as tPA, which actually dissolves the clot, in certain cases of PE. I won’t go into the details of how it is decided as to which cases of PE get lytics, but it is a direct solution to the immediate problem.

One issue we didn’t cover is that embolus generally means a clot that has traveled from another location in the body.

So where did it come from? The short answer is anywhere, but commonly they can travel from vessels in the legs/ lower extremities. While in the lower extremities these clots are often referred to as DVT (deep vein thrombosis). A DVT will often manifest itself by swelling of one extremity. These can form from long periods of inactivity such as overseas plane rides as well as being pregnant or having a history of cancer.

I mention this because a single swollen leg needs immediate evaluation. While DVT in of itself is not life threatening, if that DVT becomes a PE it can be!

Wow! What a bunch of rigmarole! What do I really need to know, you might ask?
PE is a clot that has lodged in the vasculature of the pulmonary system. It can be sudden and life threatening. They usually come from other parts of our body, so get those swollen legs seen by your doctor.

Enjoy the week and keep moving.

Ask Dr Berry a question!

(I want to apologize for all those who have tried to email me without response. It was recently brought to my attention the email I had listed was incorrect and as a result I may not have received your query. So sorry. Here is the correct address: dberrymd@hotmail.com)

David M. Berry, M.D.