CT predictors of mortality in pathology confirmed ARDS

To identify CT findings that predict mortality in acute respiratory distress syndrome (ARDS) and to identify CT findings that differentiate diffuse alveolar damage (DAD) from DAD with prominent histopathological features of organizing pneumonia (DAD-OP). Twenty-eight patients with ARDS (corroborated by open biopsy) and chest CT within 2 weeks of biopsy were included in our study. Differences in CT findings in patients with survivors versus nonsurvivors as well as for DAD versus DAD-OP were compared using Fisher's exact test. Lung involvement of greater than 80%, RA/LA ratio > 1, and varicoid traction bronchiectasis were statistically more common in nonsurvivors than in survivors (respective p values of 0.001, 0.008, and 0.038). PA dilation greater than 3 cm and RV/LV ratio greater than 0.9 were also more common in nonsurvivors than in survivors but these factors did not achieve significance. CT findings did not differentiate DAD from DAD-OP. Our study suggests that > 80% of lung involvement, RA/LA ratio > 1, and varicoid bronchiectasis predict mortality in patients with ARDS/DAD. Signs of right-sided heart failure (PA dilation greater than 3 cm and RV/LV ratio greater than 0.9) approached significance. CT findings did not differentiate DAD from DAD-OP.