What is acute respiratory distress syndrome ARDS and what causes it?

ARDS, which stands for acute respiratory distress syndrome, or sometimes adult respiratory distress syndrome (to distinguish it from a lung problem in newborns), is not a disease itself, but a type of severe acute lung dysfunction that can result from disease or injury, according to the ARDS Support Center, a clearinghouse for information.

The condition stiffens the lungs, fills them with water, and causes shortness of breath from respiratory failure. Inflammation damages microscopic air sacs called alveoli, which collapse, and tiny blood vessels called capillaries, which leak fluid into the lung. The inflammation can cause permanent scarring.

When doctors first became aware of ARDS in World War II, it was invariably fatal, but modern mechanical respirators, delivering extra oxygen, now help many to survive it.

Treatment of the condition can cause its own damage, like oxygen burns, and may leave long-term problems.

Doctors have learned to look for ARDS and treat it in patients who have survived auto accidents or heart surgery or who have illnesses like pneumonia or severe infections like septic shock, but they do not know why some of these patients suffer ARDS and others do not.