Revised ARDS definition sets out levels of severity

May 22, 2012 in Diseases, Conditions, Syndromes

An international task force this week unveiled a revised definition of acute respiratory distress syndrome (ARDS), a disease first recognized during the Vietnam War in casualties with limb injuries who had trouble breathing.

The new definition includes a distinction between the most serious cases of ARDS and cases that are less advanced, said Antonio Anzueto, M.D., of UT Medicine San Antonio, a pulmonologist who served on the ARDS Definition Task Force. The guidelines are based on evidence from data of more than 4,000 patients with ARDS, including 200 from San Antonio.

Awareness that ARDS is starting

The guidelines, called the Berlin Definition, are described in the Journal of the American Medical Association. This paper represents a more vigilant approach to identification and diagnosis of ARDS, which doesn't necessarily begin in the lungs, Dr. Anzueto said. "This new stratification of severity will make clinicians aware the process is starting and interventions have to be applied almost immediately to prevent the disease from progressing," he said.

UT Medicine is the clinical practice of the School of Medicine at The University of Texas Science Center San Antonio. Dr. Anzueto, professor of medicine at the Health Science Center and section chief of pulmonary diseases at the South Texas Veterans Health Care System, participated in an ARDS network established by the National Institutes of Health and has studied the disease for 15 years.

'White lung'

Vietnam casualties presented with lungs that were white on X-rays, and an early name for ARDS was "white lung." As many as 8 in every 10 patients died with the disease. In the 1980s a consensus conference was convened to clinically define ARDS and the research network began. New understandings about managing the disease have cut the mortality rate by more than half.

"We are learning that even though patients are surviving ARDS there are long-term consequences," Dr. Anzueto said. "Generalized weakness, emotional abnormalities and post-traumatic stress disorder are among these."

Data for review

University Hospital, a level one trauma center in San Antonio and teaching hospital of the Health Science Center, is a leading hospital for treatment of the disease. Dr. Anzueto's group contributed data to the revised definition from patients managed in the South Texas Veterans Health Care System and University Hospital.

"This is evidence-based; it is not our opinion sitting at a table smoking cigars," Dr. Anzueto said.

Factors hinder care

ARDS continues to be difficult to treat, he said, in part because conditions such as diabetes, obesity and heart disease are impacting the disease in many patients.

The JAMA article coincides with the panel's presentation of the Berlin Definition on May 23 at the American Thoracic Society 2012 Conference in San Francisco.