Techniques of continuous arteriovenous hemofiltration and hemodialysis. Renal replacement in the ICU for hypervolemic, uremic patients.

Continuous arteriovenous hemofiltration (CAVH) and continuous arteriovenous hemodialysis (CAVHD) are extracorporeal ultrafiltration techniques that permit ongoing removal of plasma water and uremic toxins. Both techniques are performed in the ICU with a minimum amount of equipment and achieve overall fluid balance more readily than intermittent hemodialysis. CAVH is used to manage hypervolemia, electrolyte imbalance, and/or mild uremia. CAVHD is used in hypercatabolic patients with acute renal failure who are hypervolemic and uremic; a dialysate fluid is used for more efficient solute removal. The most serious complications of CAVH and CAVHD relate to bleeding associated with cannulation or anticoagulation. Excess fluid and electrolyte losses may also occur.