Tuesday November 25, 2008
Acute kidney injury in ICU patients: a comparison between the RIFLE and the Acute Kidney Injury Network classifications


AKIN=Acute Kidney Injury Network (AKIN) criteria
RIFLE=Risk, Injury, Failure, Loss of Kidney Function, End-stage Kidney Disease criteria


This study evaluated the incidence of acute kidney injury and compared the ability of the maximum RIFLE and of the maximum AKIN within intensive care unit hospitalization in predicting inhospital mortality of critically ill patients.

Methods: Patients were retrospectively evaluated. Chronic kidney disease patients undergoing dialysis or renal transplant patients were excluded from the analysis.

Results: In total, 662 patients (mean age, 58.6 ± 19.2 years; 392 males) were evaluated.

• AKIN criteria allowed the identification of more patients as having acute kidney injury (50.4% versus 43.8%,) and classified more patients with Stage 1 (risk in RIFLE) (21.1% versus 14.7%), but no differences were observed for Stage 2 (injury in RIFLE) (10.1% versus 11%) and for Stage 3 (failure in RIFLE) (19.2% versus 18.1%).
• Mortality was significantly higher for acute kidney injury defined by any of the RIFLE criteria (41.3% versus 11%) or of the AKIN criteria (39.8% versus 8.5%).
• There were no statistical differences in mortality by the acute kidney injury definition/classification criteria.

Conclusions: Although AKIN criteria could improve the sensitivity of the acute kidney injury diagnosis, it does not seem to improve on the ability of the RIFLE criteria in predicting inhospital mortality of critically ill patients.

Above pearl is contributed by:

Tony Halat, MD - Clinical Instructor in Medicine, Department of Medicine, The Methodist Hospital, Weill Medical College, Cornell University

Reference: Click to get article

Acute kidney injury in intensive care unit patients: a comparison between the RIFLE and the Acute Kidney Injury Network classifications- Critical Care 2008, 12:R110