Long TE, et al. - In this retrospective study, researchers analyzed various definitions of renal recovery following postoperative acute kidney injury (AKI) and how those definitions relate to chronic kidney disease (CKD) survival and development and progression. Between 1998 and 2015, study participants included patients who had abdominal, cardiothoracic, vascular, or orthopedic surgery at a single university hospital. A total of 2,520 patients with AKI have been assessed for renal recovery. Findings suggested that risk of incident and progressive CKD within 5 years was significantly increased if patients failed to achieve a decrease in serum creatinine (SCr) to < 1.5 × baseline and if renal recovery was limited to a reduction in SCr to 1.25–1.5 × baseline within 30 days. A reduction in SCr to < 1.5 × baseline within 30 days was the definition of renal recovery that best predicted survival. Investigators observed that the one-year survival of patients whose SCr reduced to < 1.5 × baseline within 30 days was significantly better than that of a propensity score-matched control group that did not achieve renal recovery. When a consensus definition of renal recovery after AKI is established, these results should be considered.