CRRT includes a variety of modalities that use ultrafiltration and may use convection, diffusion, or both. Treatment is 24 hours per day with a blood flow of 100-200 ml/min, and a dialysate flow of 17-34 ml/min in the case of diffusive technologies. The advantages of CRRT stem from its continuous nature: both fluid and solutes shift more slowly, allowing for better hemodynamic stability and more precise solute concentrationcontrol. The gradual nature of solute removal in CRRT makes it less likely to cause cerebral edema.19 In addition, CRRT has greater cumulative solute removal than IHD due to the longer treatment time.(although I've seen other blood and dialysate flow rates commonly used) And the reasons to use CRRT over intermittent hemodialysis (IHD):
Overall, these studies suggest a lack of survival improvement with CRRT versus IHD, with a possibility of improvement with CRRT in the most severely ill ARF patients. While studies have failed to show a survival advantage for any of the modalities, there are specific conditions where a particular RRT method is preferred over another. CRRT is recommended in patients with cerebral edema or liver failure, while IHD is more appropriate in patients with an increased risk of bleeding and life-threatening hyperkalemia.Although a bit dated, the article is a great resource if you want an overview of ARF treatments, including CRRT.