ARDS leads to a buildup of fluid in the air sacs. This fluid prevents enough oxygen from passing into the bloodstream.
The fluid buildup also makes the lungs heavy and stiff, and decreases the lungs' ability to expand. The level of oxygen in the blood can stay dangerously low, even if the person receives oxygen from a breathing machine (mechanical ventilator) through a breathing tube (endotracheal tube).
ARDS often occurs along with the failure of other organ systems, such as the liver or kidneys. Cigarette smoking and heavy alcohol use may be risk factors.
Low blood pressure and organ failure
Shortness of breath
Symptoms usually develop within 24 to 48 hours of the injury or illness. Often, people with ARDS are so sick they cannot complain of symptoms.
Signs and tests
Listening to the chest with a stethoscope (auscultation) reveals abnormal breath sounds, such as crackles, which may be signs of fluid in the lungs. Often the blood pressure is low. Cyanosis (blue skin, lips, and nails caused by lack of oxygen to the tissues) is often seen.
Typically people with ARDS need to be in an intensive care unit (ICU).
The goal of treatment is to provide breathing support and treat the cause of ARDS. This may involve medications to treat infections, reduce inflammation, and remove fluid from the lungs.
A breathing machine is used to deliver high doses of oxygen and continued pressure called PEEP (positive end-expiratory pressure) to the damaged lungs. Patients often need to be deeply sedated with medications when using this equipment. Some research suggests that giving medications to temporarily paralyze a person with ARDS will increase the chance of recovery.
Treatment continues until you are well enough to breathe on your own.
Many family members of people with ARDS are under extreme stress. Often they can relieve this stress by joining support groups where members share common experiences and problems.
About a third of people with ARDS die from the disease. Those who live usually get back most of their normal lung function, but many people have permanent (usually mild) lung damage.
Many people who survive ARDS have memory loss or other quality-of-life problems after they recover. This is due to brain damage that occurred when the lungs weren't working properly and the brain wasn't getting enough oxygen.
Failure of many organ systems
Lung damage (such as a collapsed lung--also called pneumothorax) due to injury from the breathing machine needed to treat the disease
Usually, ARDS occurs during another illness, for which the patient is already in the hospital. Occasionally, a healthy person may develop severe pneumonia that gets worse and becomes ARDS. If you have trouble breathing, call your local emergency number (such as 911) or go to the emergency room.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Denis Hadjiliadis, MD, Assistant Professor of Medicine, Division of Pulmonary, Allergy and Critical Care, University of Pennsylvaniga, Philadelphia, Pa. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.