Survival and renal recovery after acute kidney injury requiring dialysis outside of intensive care units

Background The incidence of acute kidney injury requiring dialysis (AKI-D) is increasing globally and it is usually associated to chronic kidney disease (CKD) and high mortality. Literature is lacking in short- and intermediate-term data on recovery of renal function after acute kidney injury (AKI). Objectives The objective was to evaluate the overall survival and renal recovery after an episode of AKI requiring dialysis out of intensive care units (ICUs). Materials and methods Retrospective study including patients admitted in two nephrology units along a period of 2 years. Patients admitted to ICUs and renal transplant patients were excluded. Baseline renal function, mortality and glomerular filtration rate (GFR) improvement were evaluated. Results 151 consecutive adult patients with AKI requiring renal replacement therapy (RRT) were included. Mean age was 70.5 ± 15.2 years, 60.3% were males. Median baseline creatinine (bCr) and baseline GFR (bGFR) were 1.4 mg/dL and 46 mL/min/1.73 m 2 , respectively. After 1 year of follow-up, we completed the monitoring of 94 patients: 64.9% had died, 10.6% were alive on dialysis and 24.5% were alive without need for RRT. Patients with bGFR > 60 mL/min/1.73 m 2 prior to AKI episode had a slower but sustained GFR improvement through the follow-up in comparison with patients with bGFR < 60 mL/min/1.73 m 2 whose recovery was incomplete. Conclusions Patients with AKI requiring RRT have high short- and intermediate-term mortality and some require maintenance dialysis. Patients with GFR > 60 mL/min/1.73 m 2 prior to AKI had a renal recovery closer to the basal renal function than in patients with a previously diminished GFR.