Mortality in patients with respiratory distress syndrome

Mortality in Acute Respiratory Distress Syndrome (ARDS) is decreasing, although its prognosis after hospital discharge and the prognostic accuracy of Berlin's new ARDS stratification are uncertain.

We did a restrospective analysis of hospital and 6 month mortality of patients with ARDS admitted to the Intensive Care Unit of a Univeristy Hospital in Buenos Aires, between January 2008 and June 2011. ARDS was defined by PaO2/FiO2 lower than 200 mmHg under ventilation with at least 10 cm H2O of PEEP and a FiO2 higher or equal than 0.5. and the presence of bilateral infiltrates in chest radiography, in the absence of cardiogenic acute pulmonary edema, during the first 72 hs of mechanical ventilation. Mortality associated risk factors, the use of rescue therapies and Berlin's stratification for moderate and severe ARDS patients were considered.

Ninety eight patients were included; mean age was 59±19 years old, 42,9% had mayor co-morbidities; APACHE II at admission was 22±7; SOFA at day 1 was 8±3. Prone position ventilation was applied in 20,4% and rescue measures in 12,2% (12 patients with nitric oxide and 1 with extracorporeal membrane oxygenation). Hospital and 6 months mortality were 37.7 and 43.8% respectively. After logistic regression analysis, only age, the presence of septic shock at admission, Ppl >30 cmH2O, and major co-morbidities were independently associated with hospital outcome. There was no difference between moderate and severe groups (41,2 and 36,8% respectively; p=0,25).

In this cohort, including patients with severe hypoxemia and high percentage of mayor co-morbidities, ARDS associated mortality was lower than some previous studies. There was no increase in mortality after hospital discharge. There was no difference in mortality between moderate and severe groups according to Berlin's definition.