Acute respiratory distress syndrome
Alternative Names: Noncardiogenic pulmonary edema; Increased-permeability pulmonary edema; Stiff lung; Shock lung; ARDS; Acute lung injury
Acute respiratory distress syndrome (ARDS) is a life-threatening lung condition that prevents enough oxygen from getting into the blood.
See also: Infant respiratory distress syndrome
Causes of Acute respiratory distress syndrome
ARDS can be caused by any major swelling (inflammation) or injury to the lung. Some common causes include:
- Breathing vomit into the lungs (aspiration)
- Inhaling chemicals
- Pneumonia
- Septic shock
- Trauma
ARDS leads to a buildup of fluid in the air sacs. This fluid prevents enough oxygen from passing into the bloodstream.
The fluid buildup also makes the lungs heavy and stiff, and 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 (mechanical ventilator) through a breathing tube (endotracheal tube).
ARDS often occurs along with the failure of other organ systems, such as the liver or the kidneys. Cigarette smoking and heavy alcohol use may be risk factors.
Acute respiratory distress syndrome Symptoms
- Labored, rapid breathing
- Low blood pressure and organ failure
- Shortness of breath
Symptoms usually develop within 24 to 48 hours of the original injury or illness. Often, people with ARDS are so sick they are unable to complain of symptoms.
Tests and Exams
Listening to the chest with a stethoscope (auscultation) reveals abnormal breath sounds, such as crackles that suggest fluid in the lungs. Often the blood pressure is low. Cyanosis (blue skin, lips, and nails caused by lack of oxygen to the tissues) is often seen.
Tests used to diagnose ARDS include:
- Arterial blood gas
- Bronchoscopy
- CBC and blood chemistries
- Chest x-ray
- Sputum cultures and analysis
- Tests for possible infections
Occasionally an echocardiogram or Swan-Ganz catheterization may need to be done to rule out congestive heart failure, which can look similar to ARDS on a chest x-ray.
Treatment of Acute respiratory distress syndrome
Typically people with ARDS need to be in an intensive care unit (ICU).
The goal of treatment is to provide breathing support and treat the underlying cause of ARDS. This may involve medications to treat infections, reduce inflammation, and remove fluid from the lungs.
A breathing machine is used to deliver high doses of oxygen and a continuous level of pressure called PEEP (positive end-expiratory pressure) to the damaged lungs. Patients often need to be deeply sedated with medications when using this equipment.
Treatment continues until you are well enough to breathe on your own.
Support Groups
Many family members of people with ARDS are under extreme stress. Often they can relieve this stress by joining support groups where members share common experiences and problems.
See also: Lung disease - support group
Prognosis (Outlook)
About a third of people with ARDS die from the disease. Survivors usually get back normal lung function, but many people have permanent, usually mild, lung damage.
Many people who survive ARDS have memory loss or other problems with thinking after they recover. This is due to brain damage that occurred when the lungs weren't working properly and the brain wasn't getting enough oxygen.
Potential Complications
- Lung damage (such as pneumothorax) due to use of high settings on the breathing machine needed to treat the disease
- Multiple organ system failure
- Pulmonary fibrosis
- Ventilator-associated pneumonia
When to Contact a Health Professional
Usually, ARDS occurs during another illness, for which the patient is already in the hospital. Occasionally, a healthy person may develop 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.
Goldman L, Ausiello D, eds.Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders; 2008.Related Images
Learn more about Acute respiratory distress syndrome
Reviewed By: Allen J. Blaivas, DO, Clinical Assistant Professor of Medicine, UMDNJ-NJMS, Attending Physician in the Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Veteran Affairs, VA New Jersey Health Care System, East Orange, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
Copyright 2011 A.D.A.M., Inc.
