Blood clots in the lungs are also called pulmonary embolisms. Thousands of people across the United States are hospitalized every day with blood clots in their lungs. I have personally treated hundreds of such patients in the last 15 years. I am writing this article based on my personal experience, as well as a thorough review of relevant medical journals.
In this article, I will answer the most frequently asked questions about symptoms of blood clots in the lungs. These are real questions asked by patients and the families of people hospitalized with blood clots in their lungs.
Where do blood clots in the lungs come from?
Blood clots in the lungs do not actually form inside the lungs. They come from somewhere else inside the body.
Look at this picture to understand where blood clots form and how they end up in your lungs. As you can see, veins collect blood from different parts of your body, returning it to the right side of your heart. The right side of your heart pumps blood into your lungs.
Blood from the right side of your heart goes into two pulmonary arteries and into both lungs. Inside the lungs, these arteries divide into smaller branches that supply blood to the whole lung.
Blood clots form inside those large veins. Most blood clots in the lungs come from deep veins in the legs. Less commonly, they may also come from deep veins in the arms.
Clots from these veins travel to the right side of the heart, and then go inside the pulmonary arteries. They get trapped in the branches of the pulmonary arteries as they divide and get narrower.
As you can see in this picture, a larger clot is more likely to get trapped in a larger branch, while smaller clots travel further until the branch is too small to pass through.
What do blood clots in the lungs feel like?
Blood clots in the lungs happen suddenly. If you pay attention to how abruptly your symptoms started, you will be able to help your doctor think about a blood clot in the lungs as the possible cause of your symptoms.
There are many possible symptoms of blood clots in the lungs. You may only have one or two symptoms, but it is important to pay attention to how you feel. Even with seemingly mild symptoms, you feel very distressed when you have blood clots in your lungs. You feel like something just took out all your energy.
What are the symptoms of blood clots in the lungs?
Here are the actual signs and symptoms:
- Shortness of breath: Sudden shortness of breath is the most common symptom of blood clots in the lungs. It is also the symptom that appears very soon after the clots get trapped in your lungs. You feel shortness of breath within seconds of the actual event.
- Running out of breath with minimum activity: You notice a sudden change in the amount of activity you can do before running out of breath. If you had no problems walking all the way up the stairs before your symptoms started, you may notice that you have to stop to catch a breath after a few steps. You might not have any shortness of breath at rest, only get winded with activity. About 70% of people who have had blood clots in their lungs either have shortness of breath at rest or run out of breath with minimal activity.
- Chest pain: Almost 65% of people with blood clots in the lungs have chest pain. Chest pain may occur a while after blood clots get trapped in the lungs. I will explain the details in the next answer.
- Back pain: Pain from pulmonary embolisms may be felt in your back instead of your chest. I will explain the details later.
- Coughing: Coughs from blood clots in the lungs are usually dry coughs. They worsen whenever you try to take a deep breath. Almost 40% of people have sudden coughs when they get blood clots in their lungs.
- Wheezing: Almost 20% of people with new blood clots in the lungs wheeze. It is similar to wheezing that happens in people with asthma. Wheezing is a whistling sound you make while breathing. People who have never experienced an asthma attack are very alarmed by this symptom, but people who have asthma may mistake the blood clot as just a worsening of their asthma. If you have asthma, but your wheezing feels different or is associated with any other symptoms of pulmonary embolisms, you need to be concerned about it.
- Inability to lie down: More than 20% of people with blood clots in the lungs may feel that they have trouble lying down in bed, and feel the need to keep their head elevated. This symptom is more common with heart failures, but it may also happen with blood clots in the lungs, because blood clots can interfere with blood flow in the heart and lead to heart failure.
- Coughing up blood: About 10% of people with blood clots in the lungs may cough up small amounts of blood. It is very unusual to cough up large amounts of blood with a pulmonary embolism. The coughed-up blood is the blood that leaks out when small areas of the lungs get damaged due to a lack of blood flow. Blood flow worsens when blood clots block blood supply.
- Feeling like you are fainting: Some people suddenly feel very lightheaded after getting blood clots in the lungs, and feel like they are about to faint. They usually sit down or lie down quickly in order to avoid fainting.
- Actual fainting: Some people actually lose consciousness and faint as soon as they have blood clots in their lungs.
- Palpitations and a fast heart rate: Some people suddenly feel like their heart is racing when they have blood clots in their lungs.
- Fast and shallow breathing: People usually start breathing faster after they have blood clots in the lungs. Breathing may also be shallow due to pain while taking deep breaths.
- Cardiac arrest: People may suddenly go into cardiac arrest and die from blood clots in the lungs without any warning signs. We will discuss this issue in a separate question below.
What causes pulmonary embolism pain? What does it feel like?
This picture shows that your lungs are surrounded by 2 layers of linings. The inner lining goes inside the lung fissures while the outer lining is connected to the chest wall. There is a small layer of fluid between the two linings.
In your lungs, only the outer lung lining has pain-sensing nerves. To get pain from any problems inside your lungs, the outer lining must be irritated. When you have a blood clot inside a blood vessel supplying blood to part of the lungs, that portion does not get blood. That part starts to get damaged and inflamed due to the loss of blood supply. The loss of blood supply creates a wedge-shaped area that goes all the way to the inner lining of the affected lung. When the inner lining gets inflamed, it irritates the outer lining next to it, and you feel pain. It may take a while for the inflammation and irritation. The pain may worsen after some time has passed.
Pulmonary embolism chest pain:
If the section of the lung affected by the clot is next to your chest wall, you get pulmonary embolism chest pain. Pain from the irritation of the outer lining is very sharp. It can be felt over your ribs or your breasts. The pain gets worse whenever the lung linings are stretched. That happens when you cough or take a deep breath.
Pulmonary embolism back pain:
As you can see in the picture, the outer linings of the lungs cover a very large area, spanning across your chest, your back, and even a part of your neck. You can have pain from a pulmonary embolism in any of those parts. Back pain is very common with blood clots in the lungs. It is usually a sharp, stabbing back pain that gets worse with coughs and deep breaths.
Back pain from pulmonary embolisms can be felt in the middle or upper back. The pain could be on your left back or your right back. It may even be on both sides if you have blood clots in both lungs.
Can you have blood clots in both lungs?
Yes, you can have blood clots in both lungs. Blood clots in both lungs are very common. You may have chest or back pain on both sides when you have blood clots in both lungs. The chances of both lungs being involved increases with smaller blood clots. When blood with small blood clots goes out of your pulmonary artery, the clots can go to both of the main branches and end up in both lungs. On the other hand, one large clot is more likely to just settle down on one lung. As you will soon find out, having blood clots in both lungs is not necessarily worse than having it only in one lung.
What does it mean when you have multiple blood clots in the lungs?
Multiple blood clots in the lungs don’t necessarily mean a worse kind of pulmonary embolism. In fact, multiple small blood clots in both lungs have the best outcome among all blood clots in the lungs.
As you can see in the picture, the higher the number of clots, the smaller the individual clot. One large clot in a bigger branch will prevent other clots in smaller branches. That would be worse because a blockage in a large branch will block significantly more blood. Several smaller clots may appear to cover a larger surface of the lungs, but they only block blood flow in the smaller arteries. Blood will still be flowing normally in deeper parts of the lungs.
However, you may have more pain with multiple blood clots in both lungs. Smaller clots are located towards lung linings. They can get damaged from the lack of blood flow and more easily irritate the pain-sensitive nerves. A painful pulmonary embolism with several small clots involving multiple areas of both lungs may be more unpleasant, but it is not necessarily more serious. You will learn about serious types of blood clots in the lungs in next question.
Can you die from a pulmonary embolism?
Yes, you can die from a pulmonary embolism. In fact, pulmonary embolisms may be responsible for many more deaths than actually diagnosed in the hospital. In many autopsy studies of people who suddenly died in the hospital, they found out that pulmonary embolisms were present in more than half of the cases where doctors didn’t consider the possibility of pulmonary embolisms before death.
It is estimated that as high as 25% of people with new pulmonary embolisms die with an hour or two of getting the blood clot. Many of them don’t even make it to the hospital. They might suddenly collapse and die. Some of them survive if CPR is performed quickly. Read “Cardiac arrest vs heart attack” if you would like to learn more about CPR and how you can save someone in cardiac arrest.
Despite the statistics, a diagnosis of pulmonary embolism is not a death sentence. In fact, if you are hospitalized with a pulmonary embolism, you already dodged the worst part. Many people die from pulmonary embolisms because they don’t make it to the hospital. Others die because they don’t get properly diagnosed. If you are hospitalized with blood clots in the lungs, you already have two great things going in your favor: being in the hospital and being properly diagnosed.
There are more highly advanced treatment options available today than anytime in the past decade. You can read another extensive article on treatment options for blood clots in the lungs here.
How do you die from a pulmonary embolism?
Sudden death is a well known symptom of blood clots in the lungs. Let’s explore a few different scenarios where you can die from pulmonary embolisms.
As you can see in the picture, one large clot that gets trapped where the pulmonary artery divides can block the flow of blood to both lungs. The right side of the heart tries to push hard to make the blood flow, but the clot does not move, as the pathway is completely clogged. When that happens, the right heart muscles get weak, and the right heart wall bulges out. In severe cases, no blood flows out to the lungs. Your left heart needs blood coming out of the lungs to push fresh blood out into the rest of the body. With no blood going into the lungs, no blood will go out of the lungs. Your whole blood circulation stops, and you die instantly. This particular type of blood clot in the lungs is called a saddle embolus. Not all saddle emboli are fatal, because some saddle emboli still have small open areas where blood can squeeze through. A saddle embolus can be fatal if no blood or very little blood flows through it.
In this picture, you see two large clots completely blocking both pulmonary arteries. The end result will be the same as the first scenario.
In this picture, you see one large clot blocking the right pulmonary artery, and another clot blocking one major branch of the left pulmonary artery. Your right heart will have a very hard time pushing all of the blood into only one branch. The area of the lung that receives blood from the only open branch can’t tolerate the very high pressure caused by the blood going through it. It tries to fight it by narrowing the blood vessels, but the right heart fights back by pushing harder. There is no winner. High pressure may cause swelling in the lungs, making it very hard to absorb oxygen. Without oxygen, you will die soon. Less blood flowing through the lungs decreases the output of the heart, and may lead to the collapse of blood circulation and death. Many patients in these situations die before getting to the hospital. However, they can be saved if treatment is started right away.
I hope you have a clear understanding of the symptoms of blood clots in the lungs after reading this article. It is our attempt to put together the most comprehensive article that anyone can understand. After reading this article, if you still have any questions or doubts about the symptoms of blood clots in the lungs, please go to our “Contact Us” page and send us an email. We will update the article, including information that may be helpful to our readers. Remember, we will not answer any specific medical questions, but we will be happy to include any new informational topics that may be valuable to our readers.