Incidence of ARDS Following Cardiac Surgery:12-years longitudinal study

Introduction:
Lung injury with consequent development of acute respiratory distress syndrome (ARDS) is a serious complication. The first aim of our study was to determine the incidence, risk factors, and mortality of ARDS following cardiac surgery according to American-European Consensus Conference (AECC) definition. The second aim was comparing these parameters between AECC definition and the newly published, Berlin definition of ARDS.

Methods: A study was performed in cardiac surgical department in the large tertiary center. We retrospectively analyzed prospectively collected data during 12 years, between 01.2004 and 10.2016. In addition, in the period between 09.2012 and 09.2016 we compare incidence, risk factors, and mortality according to AECC definition versus Berlin definition of ARDS.

Results:
During the study period, between 01.2004 and 10.2016, 9405 patients underwent cardiac surgery. From them, at 111 patients (1.18%) developed ARDS/ALI according to the AECC definition. The mortality was 35.1% (39 patients). From the 3346 patients who underwent cardiac surgery in the period between 09.2012 and 10.2016, 37 patients (1.11%) developed ARDS/ALI according to the AECC definition, and 39 patients (1.17%) developed ARDS according to the Berlin definition. The mortality was 32.4% and 30.8% respectively (12 patients). Multivariate regression analysis identified prior cardiac surgery, complex cardiac surgery, sepsis and > 3 packed red blood cells transfusions as predictors for ARDS.

CONCLUSIONS: The development of ARDS in patients after cardiac surgery is a rare, but serious complication, associated with significant mortality. Previous cardiac surgery, complex cardiac surgery, sepsis and transfusions of >3 PRBC were significant independent predictors for developing ARDS. The significant variation in the incidence and mortality of ARDS after cardiac surgery is attributed to disparities in the definition of ARDS and the differences in the study populations. Incidence, mortality and risk factors were very similar according to AECC and Berlin definitions.