High-volume hemofiltration for septic acute kidney injury: a systematic review and meta-analysis

INTRODUCTION: High-volume hemofiltration (HVHF) is an attractive therapy for the treatment of septic acute kidney injury (AKI). Small experimental and uncontrolled studies have suggested hemodynamic and survival benefits at higher doses of HVHF than those used for the high-intensity arms of the RENAL and ATN studies. Our aim was to evaluate the effects of high-volume hemofiltration (HVHF) compared with standard-volume hemofiltration (SVHF) for septic AKI. METHODS: A systematic review and meta-analysis of publications between 1966 and 2013 was performed. The review was limited to randomized-controlled trials that compared HVHF (effluent rate greater than 50 ml/kg per hour) versus SVHF in the treatment of sepsis and septic shock. The primary outcome assessed was 28-day mortality. Other outcomes assessed were recovery of kidney function, lengths of ICU and hospital stays, vasopressor dose reduction, and adverse events. RESULTS: Four trials, including 470 total participants, were included. Pooled analysis for 28-day mortality did not show any meaningful difference between HVHF compared with SVHF (OR, 0.76; 95% CI, 0.45 to 1.29). No included studies reported statistically significant differences between groups for any of the secondary outcomes. Adverse events, including hypophosphatemia and hypokalemia, were more commonly observed in HVHF-treated patients, although reporting was inconsistent across studies. CONCLUSIONS: Insufficient evidence exists of a therapeutic benefit for routine use of HVHF for septic AKI, other than on an experimental basis. Given the logistic challenges related to patient recruitment along with an incomplete understanding of the biologic mechanisms by which HVHF may modify outcomes, further trials should focus on alternative extracorporeal therapies as an adjuvant therapy for septic AKI rather than HVHF.