[High-volume hemofiltrations]

Area of Science:

• Nephrology
• Critical Care Medicine
• Renal Replacement Therapy

Context:

• Evolving standards in hemofiltration (HF) from low ultrafiltration (UF) rates to high-volume approaches.
• Emergence of high-volume hemofiltration (HVHF) with continuous and intermittent techniques.
• Growing emphasis on evidence-based medicine in intensive care unit (ICU) protocols.

Purpose:

• To review the evolution and application of high-volume hemofiltration (HVHF) in acute renal failure (ARF).
• To highlight the impact of increased ultrafiltration rates on patient survival.
• To discuss the challenges and requirements for implementing HVHF in routine clinical practice.

Summary:

• Early hemofiltration used low ultrafiltration (UF) rates (<2 L/hr).
• Studies demonstrated that increasing UF rates to 35 ml/kg/hr in acute renal failure (ARF) improves outcomes.
• High-volume hemofiltration (HVHF) encompasses continuous (50-70 ml/kg/hr) and intermittent (100-120 ml/kg/hr) methods, with evidence suggesting a 20% survival increase in critically ill ARF patients at 35 ml/kg/hr.

Impact:

• Evidence supports higher doses of continuous veno-venous hemofiltration (CVVHF) at 35 ml/kg/hr, potentially increasing survival by 20% in critically ill ARF patients.
• These findings may lead to Stage A recommendations for CVVHF use in ICUs.
• Practical implementation faces challenges related to vascular access, blood flow, dilution procedures, membranes, fluids, and potential need for concomitant dialysis, requiring collaborative efforts between physicians and nurses.