Plasma creatinine was collected daily for 7 days and adjusted for cumulative fluid balance at the time of measurement as described by Macedo and colleagues [13]. Baseline creatinine was selected as: the pre-ICU creatinine within 7 to 365 days; or, if unavailable, the last post-discharge creatinine within 90 days; or, if unavailable, the on-admission creatinine. AKI based on plasma creatinine (AKICr) was defined as either an increase of >26.5 μmol/l within 48 hours or 50% within 7 days of admission [4]. AKI based on 6-hour urine output (AKIUO) was defined as urine output