Causes of Acute Respiratory Distress Syndrome
The causes of ARDS are divided into two categories: direct or indirect injuries to the lung. Some of the direct injuries to the lung include pneumonia, breathing stomach contents into the lung (also known as aspiration), near drowning, lung bruising from trauma (such as a car accident) and smoke inhalation from a house fire.

The indirect injuries to the lung include inflammation of the pancreas, severe infection (also known as sepsis), blood transfusions, burns, and medication reactions.

Fortunately, most patients with the above problems will not develop ARDS. It is not known why some will.

What Are Risk Factors?
While it is not clear who will develop ARDS, there are a few factors that may increase the risk for ARDS. These factors include:

A history of cigarette smoking
Oxygen use for a pre-existing lung condition
Recent high-risk surgery
Obesity
Low protein in the blood
Alcohol abuse
Recent chemotherapy