What is acute respiratory distress syndrome?

Acute respiratory distress syndrome (ARDS) is a severe lung condition. It occurs when fluid fills up the air sacs in your lungs. Too much fluid in your lungs can lower the amount of oxygen or increase the amount of carbon dioxide in your bloodstream. ARDS can prevent your organs from getting the oxygen they need to function, and it can eventually cause organ failure.

ARDS most commonly affects hospitalized people who are very ill. It can also be caused by serious trauma. Symptoms usually occur within a day or two of the original illness or trauma, and they may include extreme shortness of breath and gasping for air.

ARDS is a medical emergency and a potentially life-threatening condition.

The symptoms of ARDS typically appear between one to three days after the injury or trauma.

Common symptoms and signs of ARDS include:

ARDS is primarily caused by damage to the tiny blood vessels in your lungs. Fluid from these vessels leaks into the air sacs of the lungs. These air sacs are where oxygen enters and carbon dioxide is removed from your blood. When these air sacs fill with fluid, less oxygen gets to your blood.

Some common things that may lead to this type of lung damage include:

  • inhaling toxic substances, such as salt water, chemicals, smoke, and vomit
  • developing a severe blood infection
  • developing a severe infection of the lungs, such as pneumonia
  • receiving an injury to the chest or head, such as during a car wreck or contact sports
  • overdosing on sedatives or tricyclic antidepressants

ARDS is usually a complication of another condition. These factors increase the risk of developing ARDS:

ARDS can be a more serious condition for people who:

If you suspect that someone you know has ARDS, you should call 911 or take them to the emergency room. ARDS is a medical emergency, and an early diagnosis may help them survive the condition.

A doctor can diagnose ARDS in several different ways. There’s no one definitive test for diagnosing this condition. The doctor may take a blood pressure reading, perform a physical exam, and recommend any of the following tests:

Low blood pressure and low blood oxygen can be signs of ARDS. The doctor may rely on an electrocardiogram and echocardiogram to rule out a heart condition. If a chest X-ray or CT scan then reveals fluid-filled air sacs in the lungs, a diagnosis for ARDS is confirmed.

A lung biopsy can also be conducted to rule out other lung diseases. However, this is rarely done.


The primary goal of ARDS treatment is to ensure a person has enough oxygen to prevent organ failure. A doctor may administer oxygen by mask. A mechanical ventilation machine can also be used to force air into the lungs and reduce fluid in the air sacs.

Management of fluids

Management of fluid intake is another ARDS treatment strategy. This can help ensure an adequate fluid balance. Too much fluid in the body can lead to fluid buildup in the lungs. However, too little fluid can cause the organs and heart to become strained.


People with ARDS are often given medication to deal with side effects. These include the following types of medications:

  • pain medication to relieve discomfort
  • antibiotics to treat an infection
  • blood thinners to keep clots from forming in the lungs or legs

Pulmonary rehabilitation

People recovering from ARDS may need pulmonary rehabilitation. This is a way to strengthen the respiratory system and increase lung capacity. Such programs can include exercise training, lifestyle classes, and support teams to aid in recovery from ARDS.

The American Lung Association estimates that 30 to 50 percent of people with ARDS die from it. However, the risk of death isn’t the same for all people who develop ARDS. The death rate is linked to both the cause of ARDS and the person’s overall health. For example, a young person with trauma-induced ARDS will have a better outlook than an older person with a widespread blood infection.

Many survivors of ARDS fully recover within a few months. However, some people may have lifelong lung damage. Other side effects may include:

  • muscle weakness
  • fatigue
  • an impaired quality of life
  • compromised mental health

There’s no way to prevent ARDS completely. However, you may be able to lower your risk of ARDS by doing the following:

  • Seek prompt medical assistance for any trauma, infection, or illness.
  • Stop smoking cigarettes, and stay away from secondhand smoke.
  • Give up alcohol. Chronic alcohol use may increase your mortality risk and prevent proper lung function.
  • Get your flu vaccine annually and pneumonia vaccine every five years. This decreases your risk of lung infections.