Final answer:
Continuous venovenous hemofiltration is a renal replacement therapy used for patients with acute renal failure, employing convection, ultrafiltration, and dialysis to remove fluids, solutes, and plasma water from the blood.
Step-by-step explanation:
Continuous venovenous hemofiltration (CVVH) is a renal replacement therapy primarily used in the intensive care setting for patients with acute renal failure. It is specifically designed to remove fluids and solutes through the process of convection (1), help with volume overload conditions by removing plasma water (2), and also facilitate the removal of plasma water and solutes by incorporating dialysate into the process (3). Unlike standard hemodialysis, CVVH involves slow, continuous removal of fluids and solutes, which can be more appropriate for hemodynamically unstable patients. The combination of ultrafiltration, convection, and dialysis (4) is what enables CVVH to effectively cleanse the blood, similar to how a healthy kidney would operate.
Given the provided options, CVVH employs all these mechanisms; it removes fluids and solutes by convection, treats volume overload by extracting plasma water, uses dialysate to remove solutes, and indeed combines ultrafiltration, convection, and dialysis.