Pulmonary edema literally means an excess collection of watery fluid in the lungs. (pulmonary=lung +edema=excess fluid). However, the lung is a complex organ, and there are many causes of this excess fluid accumulation.
Regardless of the cause, fluid makes it difficult for the lungs to function (to exchange oxygen and carbon dioxide with cells in the bloodstream).
Air enters the lungs through the mouth and nose, traveling through the trachea (windpipe) into the bronchial tubes.
These tubes branch into progressively smaller segments until they reach blind sacs called alveoli. Here, air is separated from red blood cells in the capillary blood vessels by the microscopically thin walls of the alveolus and the equally thin wall of the blood vessels.
The walls are so thin that oxygen molecules can leave air and transfer onto the hemoglobin molecule in the red blood cell, in exchange for a carbon dioxide molecule.
This allows oxygen to be carried to the body to be used for aerobic metabolism and also allows the waste product, carbon dioxide, to be removed from the body.
If excess fluid enters the alveolus or if fluid builds up in the space between the alveolar wall and the capillary wall, the oxygen and carbon dioxide molecules have a greater distance to travel and may not be able to be transferred between the lung and bloodstream.
This lack of oxygen in the bloodstream causes the primary symptom of pulmonary edema, which is shortness of breath.
Symptoms and Complications of Fluid in Lungs
Fluid in the lungs can build up slowly, or it can set in very quickly, depending upon the cause. These are the symptoms to look out for and the complications fluid in the lungs can cause:
Symptoms of Acute Fluid in Lungs. When you have sudden onset of pulmonary edema, you might find it very difficult to breathe.
You could wheeze or gasp for breath, or feel as though you are drowning. You might cough up blood, have a feeling of doom or experience chest pain, sweating and a fast heartbeat.
Symptoms of Chronic Fluid in Lungs. The signs of long-term fluid in the lungs include shortness of breath when you are active, difficulty breathing with exertion, wheezing, swelling of your ankles and legs, rapid weight gain from fluid buildup, and waking up at night feeling breathless.
All of these symptoms can also lead to fatigue.
There are many complications that accompany pulmonary edema. These can include swelling of your ankles or legs, swelling of your abdomen, swelling of the liver, and buildup of fluid in the membranes surrounding your lungs.
Causes of Fluid in Lungs
A deeper understanding of the causes of fluid in the lungs can help you recognize symptoms and know when it’s time to get help. Fluid in lungs can be caused by numerous problems.
Your heart and lungs work together as a team. When one of them is not working well, the other doesn’t either. When your heart is struggling, it might not be able to move the blood effectively, thus resulting in pulmonary edema and other problems. These are common reasons for fluid in lungs:
Coronary Artery Disease. When you have a weakened heart, which means the muscle doesn’t pump as hard as it should.
The result is blood backing up into your lungs. This makes the fluid in your bloods pass into the air sacs.
Cardiomyopathy. If your heart is damaged by something other than blood flow problems, doctors call it cardiomyopathy. Your damaged heart tries to beat harder with activity, but it can’t keep up, so fluid backs up into the lungs.
Heart Valve Issues. If the valves of your heart don’t open or close completely, there are problems with blood flow. This can build up pressure in the heart.
This increase in pressure means fluid can back up into your lungs. If it happens suddenly, you might experience acute pulmonary edema – a serious emergency.
High Blood Pressure. When your blood pressure is high, your arteries have to work much harder. Over time, this can lead to fluid buildup in your lungs.
Sometimes the pulmonary edema has nothing to do with your heart and instead is caused by something else. These are some of the most common causes:
Lung Infections. If you are dealing with a problem like pneumonia, the area where the lung is affected can become swollen and filled with fluid. This edema often goes away when the underlying cause is treated.
Toxins Exposure. Some household toxins, such as ammonia or chlorine, can cause problems if you accidentally inhale them. In addition, you can get fluid in your lungs if you aspirate, such as inhaling your own vomit.
Kidney Disease. If your kidneys have trouble eliminating wastes from your body, the result can be fluid buildup in the body, including in the lungs.
Smoke Inhalation.If you get smoke into your lungs, such as from a house fire, the result can be serious pulmonary edema. That’s because many chemicals in a fire can damage the membranes in your lungs, allowing fluid to enter.
Medication Reaction. Some medications can cause serious reactions that lead to edema. Illegal drugs can also cause this problem.
Acute Respiratory Distress Syndrome (ARDS). This is a very serious disorder that comes on suddenly and can threaten your life. It can often develop from pneumonia, septic shock, severe trauma or shock.
High Altitudes. Those who exercise at over 8,000 feet might suffer from pulmonary edema. Though it isn’t clear why this happens, it is probably caused by increased pressure of the blood vessels in the lungs. This is life-threatening and must be treated immediately.
Water Inhaling. Any sort of inhaling of water, including a near-drowning, can result in fluid in the lungs. Emergency medical attention can help relieve the pressure.
Remedies for Fluid in Lungs
When you have fluid in your lungs, your doctor will immediately give you oxygen. You might then be given a variety of medications that are meant to help clear the lungs and restore your normal breathing.
Sometimes you might need a machine to help you breathe.
Prevention is always worth a pound of cure, so try to prevent pulmonary edema by managing stress, eating a healthy diet, avoid smoking, and limit salt.
You should also watch your cholesterol, be alert for signs of heart trouble and exercise regularly.
Other ways to help prevent the problem include weighing yourself daily for any signs of swelling (as a sudden increase in weight indicates water weight, not fat), get a good amount of sleep, take your blood pressure medication if applicable, stay on a good diet and listen to your doctor’s advice.
When to Seek Medical Care
Unexplained shortness of breath is not normal, and medical care should be accessed to find the reason.
Pulmonary edema can be a life-threatening situation. For persons in respiratory distress, emergency care should be sought immediately.
In many places, 911 activates the emergency response system, and this may be appropriate if the patient is in distress. In addition to struggle with breathing, these individuals may be weak, lethargic, ashen or blue in color, pale, and sweaty.
They may be coughing up frothy sputum.