Read the transcript of Dr. Green's talk on COPD on Health Matters radio or listen here
Maury Eskenazi: This is Health Matters, brought to you by IRG Physical & Hand Therapy. Maury Eskenazi, Shannon O'Kelley, physical therapist and president of IRG. We're happy to have our next guest with us. He is Dr. Ronald Green, pulmonary and sleep medicine specialist from The Everett Clinic. Thanks for coming back with us.
Dr. Green: Hey, a pleasure to be here again. Thanks for having me back.
Maury Eskenazi: Ah, we are going to talk about pulmonary embolisms. What is a pulmonary embolism?
Dr. Green: So, this is a general category of disorder called venous thromboembolic disease. Venous means veins, thrombotic means clot, and an embolism is something in the blood vessel that goes from point A to point B and should not be there. In the case of pulmonary embolism or pulmonary thromboembolism, pulmonary is lungs and embolism is something going from point A to point B. Most commonly, what happens is a blood clot, for whatever reason, forms in the veins of the legs, and that blood clot breaks off and goes up through the veins, through the heart, and it gets lodged in the lungs in the pulmonary arteries. That is called a pulmonary embolism.
Shannon O'Kelley: Now, and the reason it becomes lodged, let's dig a little deeper...
Dr. Green: Basically what happens with the circulation in the body is that the left side of the heart is a big giant muscle and it pumps the blood that has gone to the lungs and gotten oxygen through the entire body. Then those blood vessels get smaller and smaller and smaller, into capillaries, and that's where the oxygen goes from the blood into the body and where the carbon dioxide goes back into the blood. Then those capillaries change into veins and the veins drain from the body, back into the heart, and all those veins come together into the right side of the heart, and the right side of the heart is a muscle that does not have to be as strong as the left because the right side of the heart just has to push the blood through the lungs, and there is an entire tennis court's worth of capillary systems in the lung, so it is very easy to push the blood through the lungs.
Dr. Green: The lungs are like a giant filter. If anything comes up through the veins and ends up trying to go through the lungs it gets caught in the lung. That is the exact same thing that happens to blood clots. If a blood clot breaks off in the lower extremity, in the leg veins, it will break off and go to the lungs and get lodged. The reason that is a problem is because when a blood clot gets lodged in the lungs then certain segments of the lungs are not getting blood flow, but you are still breathing, so the bronchial tubes are working and the air sacs, the alveoli, in that area are working. So, there's oxygen coming in, but the oxygen is not going from the air sacs into the blood. That blood stays without oxygen and that mixes with other blood that has oxygen, and so you end up having a significant drop in your oxygen level. When that happens, there's a reflex where the arteries in the lung constrict, so there's decreased oxygen intake into the body. Then you get short of breath. Your lungs don't work very well and it's a very bad thing. If those blood clots get big enough, that actually causes blood to back up because that right side of the heart is not a strong muscle, it weakens and it fails. If you have a massive blood clot, a very huge pulmonary thromboembolic event, it causes cardiovascular collapse. The blood does not go through the lungs and your blood pressure drops dramatically, and you can pass out, or worse.
Shannon O'Kelley: And the worst part is, people can die from this.
Dr. Green: Yes.
Shannon O'Kelley: Like you said, if it's a big enough clot... This is the story I have. As a physical therapist, it was our job, the next day post-op. A lot of folks that have surgery: lower extremity surgeries, fractures, total knees, whatever it might be, and what can happen is you go in and you get your patient out of bed, they have been lying in bed, the blood has pooled in the lower extremities, they get up and they start moving around, and that emboli breaks loose and they can have episodes and sometimes people will die. I mean, after being in bed for long periods of time. Explain that situation.
Dr. Green: Exactly right. There are multiple reasons why people develop blood clots in their legs and they break off and go to the lungs, but one of the more commons ones is what we call peri-operatively or around the time of surgery. Things that cause blood clots to form in the legs include immobilization, where you are laying a long period of time without moving, such as on a long car trip or a long plane flight, or surgery. What happens in surgery is the blood clots form when you are on the operating table having the surgery, and then later on they can break off and go up to the lungs. What they do around times of surgery is they give actual injections of low-molecular weight heparin, which helps to thin the blood out, so the blood does not clot as much.
Dr. Green: So, getting up and moving after surgery is a very important thing to do.
Maury Eskenazi: Would this affect older people rather than young people as far as long flights or car rides?
Dr. Green: Pulmonary embolism tends to be more common in older people because they have more diseases that predispose them to pulmonary embolism and they also are less mobile. If they are moving around less, have chronic kidney disease, have chronic heart disease, and chronic lung disease, those things can increase the risk factors. Yes.
Shannon O'Kelley: Talk about the mechanics and the reason why when you are inactive or you are flying and you are not using your muscles how the tissue is not pumping the blood.
Dr. Green: So, our veins have valves in them and the valves basically prevent backflow, prevent the blood from going the wrong way. In order to get the blood to go the right way in the veins, they need a little stimulation and that is very well helped by movement of the muscles. The muscles help sort of squeeze that blood back up towards the heart and if you don't do that the blood tends to pool.
Shannon O'Kelley: Like long plane flights, for example, if you're sitting 12-14 hours, and also, there is a little bit of compression on your lower extremities just sitting, and that fluid pools in your lower extremities and that's a problem because when that blood going back to the heart pools, your blood has coagulation...
Dr. Green: Correct. The other risk factor is dehydration. If you are on a long plane flight, you are a little dehydrated and not moving around very much. I don't want people to get scared saying you are going to get a blood clot if you take long plane flights.
Maury Eskenazi: I'm already freaked out about flying.
Shannon O'Kelley: But, it helps to get up and move around.
Dr. Green: Yes, it does. It helps to get up and move around during a plane flight.
Dr. Green: An embolism is anything in the blood stream, either in the arteries or veins, that should not be there, that goes from point A to point B.
Shannon O'Kelley: Usually, it's a blood clot or it's a fat?
Dr. Green: Yes. Fat emboli are much less common. Those can happen with a fracture. There is fat in the insides of our bones. If you break a bone severely that fat in the bones can actually get into a blood vessel. That's called a fat embolism.
Maury Eskenazi: We're talking with Dr. Ronald Green, pulmonary and sleep medicine specialist from The Everett Clinic. So, let's freak me out more and talk about how would I know I have a blood clot. What are the symptoms?
Dr. Green: Excellent question. There are many different symptoms and not all of them occur. One of the most common symptoms is shortness of breath. All of a sudden, if a blood clot moves, you're fine one minute and the next minute this blood clot hits your lung. One minute you're fine, the next minute, boom, you're short of breath and that breathlessness just will continue for no apparent reason.
Maury Eskenazi: And it won't go away?
Dr. Green: Well, over time it may go away. Over minutes to hours it can decrease. I have seen many patients that have recurrent pulmonary thromboembolic disease, they are having recurrent clots.
Dr. Green: You can also have chest pain with it. So, you have this episode, you have a breathing problem, and then it will slowly go away. If it keeps getting worse and worse, you're throwing more and more clots, or you're throwing a very big clot.
Cough is another (symptom). If you have a large enough embolism it can cause inflammation in the bronchial tubes and that can cause a problem. Chest pain occurs as well. If you throw a big clot to your lungs, it's basically blocking all blood flow to a certain part of the lung. When a certain part of the lung doesn't get blood flow, it causes inflammation. The lungs don't have nerve cells, but the lining of the lungs have lots of nerve cells.
Dr. Green: If there is damage to the lung, the lining of the lung gets inflamed and that hurts. You can also have some inflammation which causes a little bit of bleeding and you can cough up some blood. Coughing up blood can also occur.
Shannon O'Kelley: Not a good sign.
Dr. Green: No.
Maury Eskenazi: Right. Quickly, before we go: What happens long term? Are you just on warfarin and heparin full time?
Dr. Green: Well, if there is an identifiable cause of what happened and you can stop that cause, like if you had surgery, you're not having surgery anymore. Or, young women on birth control, that increases the risk, especially young women on birth control who smoke.
Dr. Green: That can increase the risk.
Maury Eskenazi: That's not good.
Dr. Green: If you can reverse those risks, then you can take Coumadin for 3-6 months and be off of it. But, if you have a blood clot and you cannot identify what caused it, the recommendations now are long-term anticoagulation.
Dr. Green: You are basically on warfarin, which is an anticoagulant, for the rest of your life.
Shannon O'Kelley: There's that smoking thing again.
Maury Eskenazi: I know.
Shannon O'Kelley: Always bad news.
Maury Eskenazi: Dr. Ronald Green. everettclinic.com is where you want to go to and you can make an appointment to see him. Thanks so much for coming on with us.