Acute Respiratory Distress Syndrome (ARDS)

An acute inflammatory reaction in the lungs, caused by many disorders, and resulting in lung failure.

When an inflammation occurs in response to injury, disease, or infection, fluid leaks into and collects in the alveoli (air sacs) inside the lungs. This impairs the function of the alveoli which is to deliver inhaled oxygen (O2) through its membrane walls into the bloodstream where it is exchanged for carbon dioxide (CO2) by moving through the blood cell walls into the alveoli. The CO2 is then exhaled from the lungs. This function is vital in sustaining life.

ARDS symptoms include severe shortness of breath usually with rapid or shallow breathing, tiredness, drowsiness and confusion. Patients with ARDS are often unable to breathe on their own and may require a ventilator to boost their oxygen supply. 

COVID-19, the disease caused by the novel coronavirus, can cause lung complications such as pneumonia and, in the most severe cases, ARDS. People who survive ARDS and recover from COVID-19 may also have lasting pulmonary scarring. (See Long COVID).


Infectious Disease Respiration Symptoms


Alveoli (singular: Alveolus)Oxygen (02)COVID-19Long covidVentilatorRespiratory tract