What Causes Fluid in the Lungs?

A condition in which there is an excessive amount of fluid in the lungs is known as pulmonary edema. If it occurs with some suddenness, it can constitute an emergency. The condition is seldom fatal however if it is caught on time and prompt treatment is given. Symptoms can often appear somewhat suddenly when there is an infection involved, with pneumonia being a case in point. However, in cases where heart disease is the cause behind the symptoms, they may develop more slowly and not become severe until the danger zone has been entered. Most people who experience this particular condition will notice only mild symptoms, primarily consisting of feelings of congestion in the chest while experiencing a bad cold or flu. In mild cases such as these, treating the condition beyond possibly taking an expectorant is usually not necessary.

The causes, treatments, and means of preventing this disorder are discussed in some detail below. To better understand what is actually happening in your lungs and why fluid building up in them can cause a problem, it will be helpful to comprehend what alveoli are, what their role is, and why the presence of fluid in your paired, spongy respiratory organs can potentially become a significant problem.

The Anatomy of the Lungs and the Role of Alveoli

You breathe air in through your nose and mouth. The air passes down your throat and into the trachea or windpipe. From there it moves into the bronchial tree. The bronchial tree divides into two main parts called the left and right bronchi (the singular term is bronchus). Each of these two bronchi then branches out into many smaller bronchi, which gives rise to the name bronchial tree – a tree having many branches or bronchi. The bronchi, which make up the larger branches of this tree and are the major air passages, branch out still further into smaller branches called bronchioles. This branching continues approximately 25 times. Once the branching is completed, there will be a huge number of tiny branches distributed throughout the left and right lungs.

The final branching results in very small branches called the respiratory bronchioles. The respiratory bronchioles are microscopic in size. Each one has a number of tiny openings or alveolar ducts, with each opening connected to a little sac called an alveolus, the plural being alveoli. To say there are many of these alveoli would be an understatement. It is estimated that a typical, average-size lung contains roughly 300 million alveoli. These alveoli play an all-important role in keeping a person alive.

A small number of alveoli form a cluster at the end of a respiratory bronchiole somewhat similar to a cluster of grapes. On the outer surface of each individual alveolus, there are a number of tiny capillaries. Since an alveolus is microscopic in size, the same can be said for the capillaries. The junction where a capillary comes into contact with an alveolus consists of a very thin membrane – so thin that molecules of gas can pass right through it.

Oxygen molecules that are in the air that has been inhaled can easily pass through these thin membranes and into the bloodstream. The oxygen molecules attach to red blood cells, which then carry them to wherever in the body there is a need for them, which is essentially everywhere. Carbon dioxide, which is already present in the bloodstream as a waste product, passes though these same membranes, into the alveoli, and from there into the bronchioles after which it is disposed of when we exhale.

If fluid is allowed to collect in one’s lungs, it can collect in the alveoli, making it more difficult for oxygen to enter the bloodstream in quantities needed by the tissues and organs of the body. It also becomes more difficult for carbon dioxide to be effectively eliminated. If the lungs, and consequently the alveoli and bronchioles, are filled with fluid, a person will literally drown since the body will be deprived of the oxygen necessary to keep tissues alive. If only a portion of one’s lungs is filled with fluid, such as in the case with pneumonia or congestive heart failure, breathing can still become more difficult. One of the dangers in such instances is that the heart can become overworked at a time when it is also being deprived of the full amount of oxygen it needs to function properly.

Causes of Pulmonary Edema

Heart Disease – One of the primary causes of an excessive amount of fluid in the lungs is heart disease. More specifically, it is a condition known as congestive heart failure in which the chambers of the heart cannot pump blood in sufficient volume. If this is allowed to happen, blood tends to accumulate in various parts of the body, including the liver and the lungs. The latter are especially vulnerable if the heart’s left ventricles are malfunctioning since it is the left ventricles that are primarily responsible for blood backing up into the lungs. This condition is called cardiomyopathy, a condition in which the heartbeat cannot keep up with the activity of the blood flow. Cardiomyopathy is usually caused by an infection in the heart. Other causes of congestive heart failure are high blood pressure, coronary artery disease, and valves that do not open or close correctly. Wheezing, coughing, fatigue, and swelling in the ankles, legs, and feet are among the more common symptoms of congestive heart failure.

Lung Infections – Lung infections such as chronic obstructive pulmonary disease (COPD) or chronic bronchitis often have the effect of restricting blood flow through one’s lungs, which tends to cause pressure to be created in the affected blood vessels, which in turn can result in the leakage of fluids and subsequent swelling. A somewhat more common type of infection is pneumonia. Whether pneumonia is caused by a bacterium or a virus, the results are about the same. The infection causes inflammation in the affected tissues, which in turn creates a buildup of fluid and swelling.

Other Causes – Certain medications or toxins can cause pulmonary swelling, with one of the more common sources of toxins being the inhalation of smoke. Those who have kidney diseases will sometimes experience pulmonary edema since when the kidneys are not functioning properly, fluids have a tendency to build up in other parts of the body, including in the right and left lungs. Spending excessive amounts of time at high altitudes, especially if you are not used to it, can also cause fluid to accumulate in the lungs, although the reason why this can happen is not well understood. High-altitude pulmonary edema (HAPE) is best treated by descending to a lower altitude as soon as possible. If the descent cannot be accomplished in a reasonable time, HAPE can be potentially life-threatening.

Treating Pulmonary Edema

If caught early on, pulmonary edema is seldom life-threatening unless a person is in poor health or already in a weakened condition. That is likely being experienced. The second step will usually involve removing excess fluid from the lungs if there appears to be an urgent need to do so. In the meantime, diagnostic tests will be performed to determine if there is some underlying cause that needs to be addressed. In some cases, such as the case with both congestive heart failure and kidney failure, treating the underlying cause may become just as important as treating the edema itself.

Drugs and Medications – Treating pulmonary edema will require in some instances a hospital stay, and in severe cases, some time in an intensive care unit may be required. Surgery is rarely required to resolve this type of problem unless it is dictated by some underlying condition. Diuretics will at times be prescribed to lower the amount of fluids being stored in the body, which includes the lungs. Nitroglycerin can have a similar effect in that it tends to decrease the pressure caused by fluids going into the right and left lungs. Drugs can also be prescribed to dilate the blood vessels and therefore increase the blood supply to various organs and throughout the lungs themselves.

Alternative Medicine – There are certain things that you can do at home to treat pulmonary edema but relying on alternative therapies should normally not be one of them. Both alternative therapies and non-conventional medications to directly treat this respiratory condition should be only used when prescribed by a physician. Nevertheless, there are things you can do to get your lungs back into a normal condition and keep them that way. Foods rich in potassium and magnesium will often be helpful. These would include bananas, nuts, seeds, and leafy green vegetables. If you have been taking diuretics, taking in extra magnesium is often recommended since diuretics tend to deplete stores of magnesium in the body. The same is true with potassium. CoQ10, an over-the-counter supplement, is believed to reduce the amount of fluid as well as swelling that might be occurring elsewhere in your body.

Herbs and Herbal Supplements – Certain herbs may be helpful, but for a condition as serious as fluid abnormally collecting in the air sacs, it is best to check first with your doctor before placing too much reliance on herbs, or any other supplements for that matter. While some herbal medications may alleviate edema, at the same time, they may interact negatively with diuretics or other medications such as blood thinners or drugs taken to suppress the immune system. If you intend to embark on a home remedy program, it's best not to try to do it alone, but to coordinate your planned approach with your physician.

Exercise – Staying active can help as well since exercise tends to lower the amount of fluids being stored in the body. If the fluid accumulation in your lungs is due to a heart problem, you should check with your doctor to see how much physical activity you could safely be expected to tolerate.

Preventing an Excess of Fluid in the Lungs

While there is little if anything that can be done to guarantee you will never be faced with the situation of experiencing this particular problem, there are nevertheless preventive measures you can take that will significantly lessen the risk of that ever happening. Those who are at the highest risk appear to be pregnant women who are obese and those with one type or another of cardiovascular diseases.

The best way to prevent an incidence of pulmonary edema is to stay healthy. If you can control your weight, obesity will not cause you a problem in this area, and your heart may not either. The key appears to be that of keeping your heart in good health. That means, among other things, eating a healthy diet, keeping your blood pressure low, limiting your salt intake, and quitting smoking. Getting regular exercise is important too. Doing a good job of managing your stress levels can be helpful as well. Stress alone may not be the leading cause of pulmonary edema, but it can certainly contribute to other health problems, including problems with the heart and circulatory system.

It can help to weigh yourself regularly, if not daily. A sudden increase in your weight is usually due to an increase in your bodily fluids and not to a sudden increase in fat.

Understanding the role alveoli play may not provide much information as to how to go about treating an instance of fluid in your lungs, but it should at least give a good indication as to why treatment is important. Treatment usually consists of providing oxygen, removing the excess fluid, and looking for and, if possible, treating an underlying cause if one exists. Staying healthy is the best means of prevention.