Abstract P-310: DIAGNOSIS AND INCIDENCE OF ACUTE KIDNEY INJURY (AKI) IN A MIXED PAEDIATRIC INTENSIVE CARE UNIT (PICU): A RETROSPECTIVE ANALYSIS OF 2005 AND 2015

Aims & Objectives: To investigate the validity of creatinine and oliguria criteria in diagnosing AKI in PICU, and to compare AKI incidence by these criteria in two one-year cohorts ten years apart. Methods Medical records for all admissions in 2005 and 2015 were reviewed for elevated plasma creatinine and oliguria. Creatinine was categorised as the ratio of peak to patient’s baseline or upper normal limit (ratio subgroups: Mild >1.5, Intermediate >2, Severe >3). Oliguria was defined as urine output <0.5 ml/kg/hr for >8 hours (subgroups: Mild >8 hours, Intermediate >16 hours, Severe >24 hours). Plasma urea was also examined. Results There were 957 admissions in 2005 and 1246 in 2015. In 2005, 257 admissions (26.8%) had AKI by creatinine criterion (9.5% Mild, 9.7% Intermediate, 7.6% Severe). Of these, 77 (30%) met oliguria >8 hours criterion, but only 6 had oliguria within two days prior to creatinine rise. 27 admissions had oliguria without associated creatinine elevation. In 2015, 264 admissions (21.0%) had AKI by creatinine criterion (10.1% Mild, 6.9% Intermediate, 4.0% Severe). Of these, 70 (26.5%) met the oliguria criterion, with 36 occurring within two days before creatinine rise. 84 admissions had oliguria without creatinine elevation. 50% of AKI patients had uraemia >8 mmol/L, but uraemia >8 mmol/L occurred in 6% of non-AKI admissions. Conclusions Creatinine criterion best defines AKI, the incidence being high, 26.8% and 21% in the two years. Oliguria poorly defines AKI, occurring in only 28%, and in only 8% did it precede creatinine rise. Uraemia is also a poor predictor.