Latest Updates in the Management of ARDS

Abstract

• The term ARDS was first used in 1967, it is not a new disease. it had several names over the years, including shock lung, Da Nang lung (from the Vietnam war), stiff-lung syndrome, leaky capillary pulmonary edema, noncardiogenic pulmonary edema, acute lung injury, adult respiratory distress syndrome, and most recently, acute respiratory distress syndrome, or ARDS. • As of June 2012, the clinical definition ALI and ARDS has changed. This new definition addresses some of the limitations of the previous classification (AECC, 1994) There are 4 components of the new Berlin Classification of ARDS. - Timing: development of ARDS within 1 week of a known clinical insult or appearance of new or worsening of previous respiratory symptoms. - Chest imaging: bilateral opacities not fully explained by effusions, lobar/lung collapse, or nodules. - Origin of pulmonary edema: the pulmonary artery wedge pressure criterion < 18 mm Hg was removed from the definition. If there is no risk factor identifiable for ARDS, an objective evaluation with echocardiogram is required to assist in elimination of a possible hydrostatic edema. - Oxygenation: ARDS has three categories based on severity of hypoxemia. - Mild ARDS: 200 mm Hg < Pao/Fi02 < 300 mm Hg. - Moderate ARDS: 100 mm Hg < Pao/Fi02 < 200 mm Hg. - Severe ARDS: < 100 mm Hg Pao/Fi02. • ARDS has an estimated annual incidence in the United States of approximately 79 cases per 1 00,000 person-years. • ARDS may be caused by conditions eliciting lung injury directly (gastric aspiration, pulmonary contusion, pneumonia, )and those that induce lung injury indirectly like (sepsis, trauma)