There are two reasons why water retention occur in patients with lung diseases:
- The flow of the blood from the heart to the lung backs up because of increased pressure in the blood vessels. The blood buildup will leak into the surrounding tissues and lead to pulmonary edema, abdominal fluid retention, ankle and feet swelling, etc.
- The lung capillaries become leakier and cause fluid retention in lungs (pulmonary edema).
Chronic lung disease is a general term of persistent lung disorders that impairs the function of the lungs. Below are several chronic lung diseases which lead to water retention:
Smoke inhalation injury
This is an injury due to inhalation or exposure to products of combustion. Smoke contains many substances that can damage the membrane between the air sacs and the capillaries. The damage will cause fluid to enter the lungs and lead to pulmonary edema.
Acute respiratory distress syndrome (ARDS)
ARDS is a type of pulmonary edema (fluid retention in lungs) caused by serious reaction to various forms of injuries to the lung. ARDS occurs when the lungs suddenly fill with fluid and inflammatory blood cells. Common causes of ARDS including sepsis (systemic infection), severe traumatic injuries, pneumonia, shock, aspiration, major surgery, massive transfusions, trauma, smoke inhalation, reperfusion pulmonary edema, aspiration.
Lung cancer is a disease of abnormal growth of cells in tissues of the lung. The main causes of lung cancer are smoking, viral infection, and ionizing radiation. One of the symptoms of lung cancer is swelling in the neck and face. Further reading on facial swelling topic: Facial swelling / Edema.
Mesothelioma is a cancer of mesothelium; a protective lining that covers most of the body's organs. Mesothelioma is usually caused by the inhalation of asbestos (fibrous silicate mineral). In severe cases of diseases, water retention might occur and cause severe abdominal fluid retention (ascites), swelling of the cheek, neck and face.
Chronic obstructive pulmonary disease (COPD)
Enlarged view of lung tissue showing the difference between healthy lung and COPD
COPD is a disease of the lungs in which the airways become narrowed. The airways and alveoli of the lungs are normally elastic; have the ability to bounce back to original shape after each of air filling. In COPD, the elasticity is gone thus obstruct the flow of the air out of the lungs and increase the size of the lungs abnormally. Sometimes the airways might be inflamed and thickened too and block the air flow even more.
Emphysema and chronic bronchitis both is a chronic obstructive pulmonary disease. In advanced disease, COPD might increase pressure in the blood vessels in the lungs. The pressure will obstruct the blood flow from the heart. The blood buildup then leaks into the surrounding tissues causing pitting peripheral edema such as ankle and feet swelling.