Long-term sequelae of acute kidney injury in the ICU

Purpose of review Acute kidney injury (AKI) in the ICU is associated with adverse outcomes. We review the long-term consequences of AKI in ICU patients. Recent findings Observational studies show associations between AKI and mortality, prolonged length of ICU stay, dependence on mechanical ventilation, the development and progression of chronic kidney disease (CKD), and need for permanent renal replacement therapy. Few studies evaluate ICU AKI outcomes specifically, and data on long-term outcomes of survivors from this population are sparse. Little information exists comparing AKI in ICU and non-ICU settings, and prospective study designs to address such questions are problematic. AKI in the ICU should be distinguished from AKI in other clinical settings, as the underlying pathophysiology, severity of illness, and risk for permanent sequelae may be different. AKI and CKD are not mutually exclusive, but are part of a clinical spectrum in which AKI can potentiate the risk for CKD and pre-existing CKD increases risks of AKI. Summary Further research is necessary to delineate the mechanisms by which AKI may lead to CKD, and to understand how CKD enhances the risk for developing AKI. Whereas restrospective observational studies of this population exist, prospective clinical studies and trials evaluating the long-term clinical outcomes of AKI specifically in ICU patients are needed.