Early initiation of dialysis: mortality and renal function recovery in acute kidney injury patients.

INTRODUCTION The decision of when to start dialysis in Acute Kidney Injury (AKI) patients with overt uremia is strongly established, however, when blood urea nitrogen (BUN) levels is < 100 mg/dL the timing of initiation of dialysis remains uncertain. PURPOSE The aim of this study was to assess mortality and renal function recovery AKI patients started on dialysis at different BUN levels. METHODS This was a retrospective study performed at Medical School Hospital, São Paulo, Brazil, enrolling 86 patients underwent to dialysis. RESULTS Dialysis was started when BUN < 75 mg/dl in 23 patients (Group I) and BUN > 75 mg/dl in 63 patients (Group II). Hypervolemia and mortality were higher in Group I than in Group II (65.2% vs. 14.3% - p < 0.05, 39.1% vs. 68.9%- p < 0.05, respectively). Among survivors, the rate of renal function recovery was higher in Group I (71.4% and 36.8%, respectively--p < 0.05). Multivariate analysis showed that sepsis, age > 60 years, peritoneal dialysis and BUN > 75 mg/dl at dialysis initiation were independently related with mortality. CONCLUSIONS Lower mortality and higher renal function recovery rates were associated with early dialysis initiated at lower BUN levels in AKI patients.