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ARDS (Acute Respiratory Distress Syndrome)

Acute respiratory distress syndrome (ARDS) is a rapidly developing, life-threatening condition in which the lung is injured to the point where it can't properly do its job of moving air in and out of the blood.

Doctors first recognized the syndrome in 1967, when they came across 12 people who developed sudden breathing problems and rapid lung failure. All of them had similar patchy spots on their chest X-rays.

At first, the condition was called adult respiratory distress syndrome, so people would not confuse it with a similar type of lung distress seen in infants. But because ARDS can also occur in children ages 1 and older, doctors now refer to it as acute respiratory distress syndrome. Acute means sudden or new.

ARDS may also be called acute lung injury, noncardiac pulmonary edema, and increased-permeability pulmonary edema. In the past it was also called stiff lung, wet lung, and shock lung.

According to the National Heart Lung and Blood Institute, about 190,000 people in the U.S. develop ARDS each year.


What Causes ARDS?

ARDS can occur when a major injury or extreme inflammation somewhere in the body damages the small blood vessels, including those in the lungs. As a result, the lungs are unable to fill with air and can't move enough oxygen into the bloodstream.

The lung damage can be direct or indirect.

Conditions that can directly injure the lungs and possibly lead to ARDS include:

  • Breathing in smoke or poisonous chemicals
  • Breathing in stomach contents while throwing up (aspiration)
  • Near drowning
  • Pneumonia
  • Severe acute respiratory syndrome (SARS), a lung infection

Conditions that can indirectly injure the lungs and possibly lead to ARDS include:

  • Bacterial blood infection (sepsis)
  • Drug overdose
  • Having many blood transfusions
  • Heart-lung bypass
  • Infection or irritation of the pancreas (pancreatitis)
  • Severe bleeding from a traumatic injury (such as a car accident)
  • Severe hit to the chest or head

The conditions that have most commonly been linked to ARDS include sepsis, traumatic injury, and lung infections such as pneumonia. However, it's important to note that not everyone who has these conditions develops ARDS. Doctors are not sure why some people develop ARDS and others do not.

What Are the Symptoms of ARDS?

Symptoms of ARDS come on suddenly, usually within hours or days of the event that initially caused injury to the lung.

ARDS is defined by three main signs and symptoms:

  • Rapid breathing
  • Feeling like you can't get enough air in your lungs
  • Low oxygen levels in your blood, which can lead to organ failure and symptoms such as rapid heart rate, abnormal heart rhythms, confusion, and extreme tiredness

Other symptoms can occur, depending on the event that caused the ARDS. For example, if pneumonia is causing the ARDS, symptoms may also include chest pain and fever.

ARDS is a medical emergency. If you have symptoms of ARDS, call 911. The severe loss of oxygen can rapidly lead to death without prompt treatment.

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