Acute Respiratory Distress Syndrome

Condition 101

What is the definition of Acute Respiratory Distress Syndrome?

Acute respiratory distress syndrome (ARDS) is a life-threatening lung condition that prevents enough oxygen from getting to the lungs and into the blood. Infants can also have respiratory distress syndrome.

What are the alternative names for Acute Respiratory Distress Syndrome?

Noncardiogenic pulmonary edema; Increased-permeability pulmonary edema; ARDS; Acute lung injury

What are the causes for Acute Respiratory Distress Syndrome?

ARDS can be caused by any major direct or indirect injury to the lung. Common causes include:

  • Breathing vomit into the lungs (aspiration)
  • Inhaling chemicals
  • Lung transplant
  • Pneumonia
  • Septic shock (infection throughout the body)
  • Trauma

Depending on the amount of oxygen in the blood and during breathing, the severity of ARDS is classified as:

  • Mild
  • Moderate
  • Severe

ARDS leads to a buildup of fluid in the air sacs (alveoli). This fluid prevents enough oxygen from passing into the bloodstream.

The fluid buildup also makes the lungs heavy and stiff. This decreases the lungs' ability to expand. The level of oxygen in the blood can stay dangerously low, even if the person receives oxygen from a breathing machine (ventilator) through a breathing tube (endotracheal tube).

ARDS often occurs along with the failure of other organ systems, such as the liver or kidneys. Cigarette smoking and heavy alcohol use may be risk factors for its development.

What are the symptoms for Acute Respiratory Distress Syndrome?

Symptoms usually develop within 24 to 48 hours of the injury or illness. Often, people with ARDS are so sick they cannot complain of symptoms. Symptoms can include any of the following:

  • Shortness of breath
  • Fast heartbeat
  • Low blood pressure and organ failure
  • Rapid breathing

What are the current treatments for Acute Respiratory Distress Syndrome?

ARDS often needs to be treated in an intensive care unit (ICU).

The goal of treatment is to provide breathing support and treat the cause of ARDS. This may involve medicines to treat infections, reduce inflammation, and remove fluid from the lungs.

A ventilator is used to deliver high doses of oxygen and positive pressure to the damaged lungs. People often need to be deeply sedated with medicines. During treatment, health care providers make every effort to protect the lungs from further damage. Treatment is mainly supportive until the lungs recover.

Sometimes, a treatment called extracorporeal membrane oxygenation (ECMO) is done. During ECMO, blood is filtered through a machine to provide oxygen and remove carbon dioxide.

What are the support groups for Acute Respiratory Distress Syndrome?

Many family members of people with ARDS are under extreme stress. They can often relieve this stress by joining support groups where members share common experiences and problems.

What is the outlook (prognosis) for Acute Respiratory Distress Syndrome?

About one third of people with ARDS die of the disease. Those who live often get back most of their normal lung function, but many people have permanent (usually mild) lung damage.

Many people who survive ARDS have memory loss or other quality-of-life problems after they recover. This is due to brain damage that occurred when the lungs were not working properly and the brain was not getting enough oxygen. Some people can also have post-traumatic stress after surviving ARDS.

What are the possible complications for Acute Respiratory Distress Syndrome?

Problems that may result from ARDS or its treatment include:

  • Failure of many organ systems
  • Lung damage, such as a collapsed lung (also called pneumothorax) due to injury from the breathing machine needed to treat the disease
  • Pulmonary fibrosis (scarring of the lung)
  • Ventilator-associated pneumonia

When should I contact a medical professional for Acute Respiratory Distress Syndrome?

ARDS most often occurs during another illness, for which the person is already in the hospital. In some cases, a healthy person has severe pneumonia that gets worse and becomes ARDS. If you have trouble breathing, call your local emergency number (such as 911) or go to the emergency room.


Lee WL, Slutsky AS. Acute hypoxemic respiratory failure and ARDS. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 100.

Matthay MA, Ware LB. Acute respiratory failure. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 96.

Seigel TA. Mechanical ventilation and noninvasive ventilatory support. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 2.

Latest Research

Latest Advance
  • Condition: COVID-19
  • Journal: Tidsskrift for den Norske laegeforening : tidsskrift for praktisk medicin, ny raekke
  • Treatment Used: Corticosteroids
  • Number of Patients: 1
  • Published —
This study evaluated the effectiveness of corticosteroids (drugs that can effectively reduce inflammation) in a patient with severe COVID-19 (a pandemic infection caused by a coronavirus).
Latest Advance
  • Condition: Acute Acalculous Cholecystitis with COVID-19
  • Journal: Annals of medicine and surgery (2012)
  • Treatment Used: Laparoscopic Cholecystectomy with Percutaneous Gallbladder Drainage
  • Number of Patients: 1
  • Published —
This case report describes a patient with acute acalculous cholecystitis and a COVID-19 infection that was treated using a laparoscopic cholecystectomy after a percutaneous gallbladder drainage.
Latest Advance
  • Condition: Recurrent Pneumothorax with COVID-19
  • Journal: Respiratory medicine case reports
  • Treatment Used: Tube Thoracostomy under Conventional Chest Tube
  • Number of Patients: 1
  • Published —
This case report describes a patient with recurrent pneumothorax that was related to a COVID-19 infection that was treated using a tube thoracostomy under a conventional chest tube under suction.
Latest Advance
  • Condition: COVID-19
  • Journal: BMJ open respiratory research
  • Treatment Used: Continuous Positive Airway Pressure (CPAP) in Prone Position
  • Number of Patients: 24
  • Published —
This study tested the safety and efficacy of using a CPAP machine on patients in a conscious prone position to treat their COVID-19 infections.

Clinical Trials

Clinical Trial
  • Status: Recruiting
  • Study Type: Procedure
  • Participants: 110
  • Start Date: September 3, 2020
Early Use of Prone Position in Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome
Clinical Trial
  • Status: Recruiting
  • Study Type: Drug
  • Participants: 20
  • Start Date: August 24, 2020
Partial Neuromuscular Blockade in Acute Respiratory Distress Syndrome