Correlation between the severity of acute kidney injury and mortality in intensive care unit according to RIFLE and AKIN criteria

Acute renal failure, which is defined as an abrupt and progressive deterioration, is an important factor of increase in hospital mortality and morbidity, especially in intensive care units. Recently, as local and relatively limited damages in renal tissue can cause dramatic functional effects, the term ?acute kidney injury (AKI)? is recommended to be more descriptive.The reported AKI-related mortality rates in intensive care units are quite variable. Lack of a uniform definiton for AKI is the main reason of this variability. As AKI is a reversible process, it is necessary to have a standart definition to manage it better. Based on this opinion, several consensus reports including AKI staging criterias were published. AKIN and RIFLE criterias are two widely used staging systems among these. The studies showed that there is a stepwise increase in mortality with increasing severity of AKI.The aim of this study is to evalute the relationship between mortality rate and the severity of AKI according to RIFLE and AKIN criterias in patients, who were followed in intensive care unit.In this study, we eveluated 155 patients retrospectively, who was diagnosed with AKI during their follow-up in the Intensive Care Unit of Internal Medicine Department of Dokuz Eylul University Medical Faculty Hospital. Both of RIFLE and AKIN criterias are used to determine the severity of AKI for each patient. Serum creatinin levels and urine output were used in staging.When RIFLE criterias were used, the rates of patients in risk, injury and failure were found as 9 %, 25.2 % and 65%, respectively. When AKIN criterias were used, the rates of patients in stage 1, 2 and 3 were found as 21.3 %, 31% and 45.2 %, respectively. The mean follow-up period was 12.7 ± 12 days and the mortality rate was 76.8%.There was no significant difference between the mortality rates of AKI stages in both staging systems. The rate of patients with sepsis or SIRS was 59.7%. The rates of patients undergoing invasive mechanical ventilation, vasoppresor and hemodyalisis were 92.3 %, 95.5 % and 33.8 %, respectively. The mean SAPS II and APACHE II scores were 24.6 ±8.2 and 55.8±19.6, respectively.Applying the staging systems, which ignore the ethiology of AKI, in clinical practice is quite difficult, especially in septic AKI and critically ill patients. Modifications of existing staging systems in this direction can improve their effectiveness in different circumstances.