This document discusses different modalities of continuous renal replacement therapy (CRRT) for critically ill patients with acute kidney injury, including CVVH, CVVHDF and CVVHD. It summarizes evidence from randomized controlled trials and systematic reviews showing no significant differences in mortality or renal recovery rates between CRRT and intermittent hemodialysis. Slow low efficiency daily dialysis (SLED) is presented as a hybrid therapy that combines benefits of CRRT and economics of intermittent hemodialysis. A cost analysis shows CRRT is more expensive than SLED due to additional consumables and fluids required. The conclusion is that while CRRT may provide higher blood pressure, there is no evidence it improves survival over intermittent