Background: Acute kidney injury (AKI) in critically ill patients is associated with high mortality rates. Few studies have
evaluated the epidemiology of AKI in critically ill trauma patients.
Material and Method: Between January 2007 and December 2008, 265 patients who admitted in trauma ICU of the level 1
trauma center were included in this study. Demographic data, mechanism of injury, admission vital signs, GCS, ISS, TRISS,
APACHE II scores, ICU mortality, 28-day mortality, ICU length of stay (LOS), hospital LOS, need for dialysis, and mode of
dialysis were collected. The AKI patients were classified by RIFLE and AKIN criteria.
Results: 101 of 265 patients (38.1%) had AKI according to RIFLE criteria and 132 of 265 patients (49.8%) according to
AKIN criteria. The mortality rate of patients with AKI was 40.2%. The patients with AKI were increased 28-day mortality (OR 12.8, 95% CI 4.88 to 33.56, p<0.001) and ICU mortality (OR 15.61, 95% CI 5.97 to 40.77, p<0.001). Higher grading of AKI according to RIFLE or AKIN classifications was associated with higher mortality (p<0.001).
Conclusion: 50% of trauma ICU patients in Thailand develop AKI according to RIFLE and AKIN criteria. AKI in critically ill trauma patients was associated with ICU LOS, hospital LOS and mortality.

Keywords: Acute kidney injury, AKI, Critically ill trauma patient