Fluid Balance, Diuretic Use, and Mortality in Acute Kidney Injury

Background and objectives Management of volume status in patients with acute kidney injury (AKI) is com-plex, and the role of diuretics is controversial. The primary objective was to elucidate the association be-tween fluid balance, diuretic use, and short-term mortality after AKI in critically ill patients. Design, setting, participants, & measurements Using data from the Fluid and Catheter Treatment Trial (FACTT), a multicenter, randomized controlled trial evaluating a conservative versus liberal fluid-manage-ment strategy in 1000 patients with acute lung injury (ALI), we evaluated the association of post-renal in-jury fluid balance and diuretic use with 60-day mortality in patients who developed AKI, as defined by the AKI Network criteria. Results 306 patients developed AKI in the first 2 study days and were included in our analysis. There were 137 in the fluid-liberal arm and 169 in the fluid-conservative arm (P 0.04). Baseline characteristics were similar between groups. Post-AKI fluid balance was significantly associated with mortality in both crude and adjusted analysis. Higher post-AKI furosemide doses had a protective effect on mortality but no signif-icant effect after adjustment for post-AKI fluid balance. There was no threshold dose of furosemide above which mortality increased. Conclusions A positive fluid balance after AKI was strongly associated with mortality. Post-AKI diuretic therapy was associated with 60-day patient survival in FACTT patients with ALI; this effect may be medi-ated by fluid balance