A mortality score for acute respiratory distress syndrome: predicting the future without a crystall ball.

Prognostic scores, such as APACHE III, SAPS 3 and MPM III0, can provide estimates of the probability of death for individual patients in the ICU. However, there are controversies regarding the use of these scores for predicting outcome in patients with ARDS. Some studies have developed scores to predict mortality at bedside in this patient population (10,11,23,24); however, all had limitations such as the use of non-protective mechanical ventilation strategies and small sample sizes. Villar et al. designed an outcome score (APPS) that combines variables that are readily and routinely obtained at bedside 24 h after ARDS diagnosis (age, PaO2/FiO2, and plateau pressure). They reported that the APPS can be useful for predicting patients at high risk of fatal outcome, selecting patients with ARDS in clinical studies, and guiding ventilator management. Certainly, further multicenter studies should be performed for external validation of this score in other clinical management settings and countries.