Bedside estimates of dead space using end-tidal CO are independently associated with mortality in ARDS.

Purpose: In acute respiratory distress syndrome (ARDS), dead space fraction has been independently associated with mortality. We hypothesized that early measurement of the difference between arterial and end-tidal CO (arterial-ET difference), a surrogate for dead space fraction, would predict mortality in mechanically ventilated patients with ARDS.

Methods: We performed two separate exploratory analyses.