Validity of low-efficacy continuous renal replacement therapy in critically ill patients

The 1980s saw the use of continuous arteriovenous hemofiltration whose intensity hemofiltration rate was only 3 or 4 mL kg⁻¹ h⁻¹. With the installation of a blood pump, this dose went up to 8 or 10 mL kg⁻¹ h⁻1, and continued to increase, reaching about 20 mL kg⁻¹ h⁻¹ by the year 2000. Some studies found that a higher dose could be beneficial, and the world rapidly followed the trend, increasing the dose up to 35 mL kg⁻¹ h⁻¹. Then, two randomized control trials, namely the VA/NIH Acute Renal Failure Trial Network study and the RENAL study, came along in succession which changed the Kidney Disease: Improving Global Outcomes (KDIGO) recommendation to 20 to 25 mL kg⁻¹ h⁻¹. However, no good evidence exists to support this. Our recent multicenter retrospective studies from the JSEPTIC CRRT database show that the Japanese continuous renal replacement therapy dose of (14.3 mL kg⁻¹ h⁻¹) does not seem to have worse outcomes when compared with a higher dose.