Acute respiratory distress syndrome (ARDS)


Acute respiratory distress syndrome (ARDS) is a condition characterized by the accumulation of fluid in the small, elastic air sacs (alveoli) within the lungs. Less oxygen enters your circulation because the fluid in alveoli prevents your lungs from filling with enough air. As a result, your organs are deprived of the oxygen they require to function.

Individuals with pre-existing critical illnesses or severe injuries have an increased susceptibility to the development of ARDS. The predominant manifestation of ARDS, characterized by shortness of breath, usually emerges within a few hours to several days subsequent to the initial injury or infection that precipitated its onset.

A significant number of individuals afflicted with ARDS do not survive the condition. The likelihood of mortality is heightened by factors such as advanced age and the severity of the illnesses. For those who do manage to survive ARDS, the outcomes can vary considerably: some individuals experience a complete restoration of their health, while others endure lasting lung impairment that persists throughout their lifetime.


The severity of ARDS’s signs and symptoms might vary depending on the condition’s cause, its severity, and whether or not underlying heart or lung illness is present.

The individual may experience:

  • Profound shortness of breath
  • Difficult and abnormally fast breathing
  • Low blood pressure
  • Confusion and extreme fatigue

ARDS (Acute Respiratory Distress Syndrome) typically develops following a severe illness or injury, primarily affecting individuals who are already hospitalized.


The smallest blood vessels in the lungs leak fluid into the tiny air sacs where the blood is oxygenated, which is the mechanical cause of ARDS. This fluid is typically kept in the vessels by a protective barrier. However, severe disease or injury can harm the membrane, resulting in fluid leakage and ARDS.

ARDS’ underlying causes include:

  • Sepsis. Sepsis, a dangerous and widespread bloodstream infection, is the most typical cause of ARDS.
  • Head, chest or other major injury. Accidents that cause direct damage to the lungs or the area of the brain that regulates respiration.
  • Severe pneumonia. All five lung lobes are typically affected by severe pneumonia instances.
  • Coronavirus disease 2019 (COVID-19). Severe COVID-19 patients may experience ARDS.
  • Inhalation of harmful substances. As well as inhaling (aspirating) vomit or experiencing a near-drowning episode, breathing in large amounts of smoke or chemical fumes can cause ARDS.
  • Others. Burns, heavy blood transfusions, and pancreatitis (pancreas inflammation).

Risk factors

The majority of patients with ARDS are already in the hospital for another illness, and many are in serious condition. If you have sepsis, a widespread infection in your bloodstream, you are especially at danger.

People with a history of chronic alcoholism are at a higher risk of developing ARDS and have an increased likelihood of mortality associated with the condition.