Epidemiology of Acute Kidney Injury in Intensive Care Septic Patients Based on the KDIGO Guidelines

Background: Acute kidney injury (AKI) is a common complication of sepsis, which is associated with higher risks of adverse outcomes. Recently, kidney disease: improving global outcomes (KDIGO) recommended a new guideline for AKI, including a little modification on the AKI staging criteria.

Methods: This retrospective study included 211 septic patients admitted to the intensive care unit (ICU) at Xiangya Hospital, Central South University from January 2008 to January 2011. AKI was diagnosed and classified according to the KDIGO or acute kidney injury network (AKIN) criteria. Differences between the AKI and non-AKI groups for baseline characteristics, laboratory examinations, etiology, outcomes, as well as the risk factors for AKI and 28-day mortality were analyzed. The reliability of the KDIGO criteria was also evaluated by comparing it with the AKIN criteria.

Results: The overall incidence of AKI in septic patients was 47.9%, and the 28-day mortality was 32.7%. The incidence of AKI was significantly higher in patients with more severe sepsis. Indicators of hepatic and respiratory function were significantly worse in the AKI group. Furthermore, a higher proportion of patients were infected with Enterobacter cloacae in the AKI group. The independent risk factors for AKI were shock, the number of organ failures, blood urea nitrogen (BUN) levels, and the use of vasopressors. The independent risk factors for mortality were BUN and creatine kinase-MB (CK-MB) levels. Both the KDIGO criteria and the AKIN criteria were significantly associated with 28-day mortality.

Conclusions: The incidence and 28-day mortality of AKI were very high in ICU septic patients. Greater attention should be paid to AKI-induced hepatic and respiratory dysfunction in clinical practice. Patients with an intra-abdominal source of infection were more likely to develop AKI. KDIGO criteria are reliable in AKI staging.