Acute Respiratory Distress Syndrome (ARDS)

Acute respiratory distress syndrome (ARDS) is a life-threatening lung injury caused by sepsis, pneumonia, COVID-19 and other conditions. ARDS tends to develop within a few hours to few days of the event that caused it, and can worsen quickly. People with ARDS may have to be put in an intensive care unit (ICU) and on a ventilator to help them breathe.


Healthy air sacs (alveoli) in a person's lungs compared to unhealthy air sacs filled with fluid and low oxygen levels.
Acute respiratory distress syndrome (ARDS) happens when fluid builds up in the tiny air sacs in your lungs. It causes critically low oxygen levels.

What is acute respiratory distress syndrome (ARDS)?

Acute respiratory distress syndrome (ARDS) is a lung injury that happens when fluids build up in small air sacs (alveoli) in your lungs. ARDS prevents your lungs from filling up with air and causes dangerously low oxygen levels in your blood (hypoxia). Healthcare providers typically diagnose a person as having mild, moderate or severe respiratory distress syndrome. They determine that level by comparing the level of oxygen in your blood with the amount of oxygen that needs to be given to achieve a healthy blood oxygen level.

ARDS prevents other organs such as your brain, heart, kidneys and stomach from getting the oxygen they need to function. ARDS is dangerous and can lead to several serious and life-threatening problems.

ARDS typically happens when a person is in the hospital receiving treatment for an infection, illness or trauma. If you’re not hospitalized and experience symptoms of ARDS, get medical attention immediately.

What are the three stages of ARDS?

Healthcare providers sometimes classify ARDS into three stages: exudative, proliferative and fibrotic. This classification mainly describes the level of inflammation and fluid buildup, and the subsequent repair process that your lungs go through to heal. Not all people progress to the third stage, which mainly describes the formation of scar tissue in your lungs and a prolonged need for ventilation.

How common is ARDS?

ARDS affects about 200,000 people in the United States and 3 million people worldwide every year. ARDS causes around 10% of all intensive care unit (ICU) admissions . It’s the reason at least 25% of people require mechanical ventilation in a hospital setting.


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Symptoms and Causes

What are the symptoms of acute respiratory distress syndrome (ARDS)?

Symptoms of ARDS depend on the cause and severity of the case, as well as preexisting lung or heart conditions. Symptoms include:

How quickly can acute respiratory distress syndrome (ARDS) develop?

ARDS tends to develop within a few hours to a few days of the event that caused it. ARDS can worsen rapidly.

What causes acute respiratory distress syndrome (ARDS)?

Causes of ARDS include:

  • Sepsis: Sepsis is the most common cause of ARDS. It can happen when you have a serious infection in your lungs (pneumonia) or other organs with widespread inflammation.
  • Aspiration pneumoniaAspiration of stomach contents into your lungs may cause severe lung damage and ARDS. Aspiration is when food, liquid or other substances get into your airway and lungs.
  • Blood transfusions: You’re at risk for ARDS if you receive more than 15 units of blood in a short period of time.
  • COVID-19: The COVID-19 virus may develop into severe ARDS.
  • Pancreatitis: Severe inflammation in your pancreas.
  • Major trauma or burns: Accidents and falls may directly damage your lungs or other organs in your body and trigger severe inflammation in your lungs.
  • Inhalational injury: Breathing and exposure to high concentrations of chemical fumes or smoke.
  • Drug overdose: An overdose on drugs like cocaine and opioids.
  • Drowning or near drowning: Drowning causes water to get into your lungs, causing damage.

Who’s at risk for ARDS?

People who are already in the hospital due to an injury or illness are most at risk for ARDS. But, just because you’re hospitalized, doesn’t mean you’ll end up in respiratory distress. Some factors that can increase your risk include:


What are complications of acute respiratory distress syndrome (ARDS)?

Complications and problems from ARDS may develop while you’re in the hospital or after you go home, like:

Diagnosis and Tests

What tests are done to diagnose acute respiratory distress syndrome (ARDS)?

Healthcare providers diagnose ARDS based on a physical exam and the results of several tests. Since the symptoms of ARDS are similar to chronic lung or heart conditions, your provider may need to rule out other causes.

A healthcare provider may order a combination of tests, including:

  • Chest X-ray to measure fluid in your lungs.
  • A blood test to measure oxygen levels in your blood and determine the severity of ARDS.
  • Echocardiogram (ultrasound of your heart) to evaluate heart function.
  • Electrocardiogram (or EKG) to measure your heart’s electrical activity.
  • A fingertip sensor (pulse oximetry) for constant monitoring of oxygen levels.
  • computed tomography (CT) scan to provide more detailed information about your lungs.
  • Sampling of secretions from your airways to find the cause of an infection.


Management and Treatment

How is acute respiratory distress syndrome (ARDS) treated?

Treatment for ARDS involves increasing oxygen levels in your blood to prevent organ failure. People with ARDS need a mechanical ventilator and/or oxygen therapy to improve blood oxygen levels. They also need help to open up the airways that have closed due to damage.

Your healthcare provider may take steps to minimize complications from ARDS. These include:

  • Sedation to manage pain and sedatives help you relax.
  • Placing you in a prone position (on your stomach), instead of on your back.
  • Breathing tests to determine when it’s safe to remove the tube and ventilator.
  • Blood thinners to prevent clots.
  • Diuretics to remove extra fluid from your body.
  • Medications to minimize fluid buildup in your lungs.
  • Antibiotics to prevent or treat infection.
  • Active mobility and physical therapy to prevent muscle weakness.
  • Pulmonary rehabilitation to help strengthen your lungs and increase lung capacity.

How long does ARDS take to resolve?

It depends on how severe it is and how long it takes a person’s lungs to heal. Most studies estimate it takes between six months to a year, on average, for a person to regain their usual lung function after ARDS. But some people don’t regain full lung function.

What is the ARDS survival rate?

Survival rates for ARDS are around 55% to 70% when treatment is prompt. If treatment is delayed or other organs begin to fail, survival rates are lower.

Factors like the underlying medical conditions, health history and how severe the respiratory distress is all go into determining the outlook. Your healthcare provider will tell you what to expect.


Can you prevent acute respiratory distress syndrome (ARDS)?

There’s no way to prevent acute respiratory distress syndrome (ARDS). But you may be able to prevent it from being severe by seeking immediate medical attention if you have symptoms of respiratory distress, or if you have a lung injury or other disease. You can lower your risk of getting severe ARDS by quitting smoking and avoiding alcohol.

Outlook / Prognosis

What is the outlook for acute respiratory distress syndrome (ARDS)?

ARDS can be life-threatening and scary. But improved care and ventilator treatments — including having people lay face down (prone) to improve oxygen flow — are helping more people survive and reduce ARDS complications. The outlook is typically better in people younger than 65 and when trauma or a blood transfusion causes ARDS.

Recovery from ARDS may take a long time. Most people who are taken off a ventilator can breathe freely. Some recover completely, but others may develop chronic lung problems that require care by lung specialists (pulmonologists).

Can your lungs recover from ARDS?

Yes, your lungs can recover from ARDS. The exact amount of time varies depending on how much lung damage you have. Most people regain their lung function within two years, although several factors go into that estimate.

Living With

How do I take care of myself?

Life after ARDS can be challenging. Have patience with yourself as you navigate recovery and lean on friends and family members for support. You may need help performing everyday tasks while your lungs regain function. Talk to your healthcare provider about support groups or other resources available to help you get your strength back.

When should I see my healthcare provider?

Most people who have ARDS are already in the hospital due to an injury or illness. A healthcare provider is usually already checking on you and monitoring your vital signs. It’s important to share all your symptoms with your providers. If you ever experience symptoms of ARDS and aren’t in a hospital, contact 911, or your local emergency services, immediately.

Additional Common Questions

Are ARDS and COVID-19 the same?

No, they aren’t the same. People with COVID-19 can develop ARDS when the virus gets into their lungs.

What is the survival rate for ARDS in people with COVID-19?

Researchers are always learning more about the COVID-19 virus. Most studies conclude that the survival rate for a person with both COVID-19 and ARDS is about 50% to 60%. But many factors go determining if a person survives ARDS and COVID-19, including health history and other medical conditions.

A note from Cleveland Clinic

Time in the ICU can be traumatic and hard. People recovering from ARDS may not be able to go back to everyday life quickly, and you’ll need support. Getting professional help and advice is important along the road to recovery from ARDS. Ask your healthcare team about any post-intensive care recovery programs in your area and online support groups that are available.

Medically Reviewed

Last reviewed on 12/07/2023.

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