Nursing management of continuous arteriovenous hemodialysis

Intermittent hemodialysis in critically ill patients is often accompanied by circulatory instability and hypotension. Slow continuous ultrafiltration and continuous arteriovenous hemofiltration were developed to manage fluid balance and electrolyte abnormalities without circulatory side effects. To improve urea clearance a dialysate was added to the extracorporeal circuit. This technique is called continuous arteriovenous hemodialysis (CAVHD) or, when large amounts of ultrafiltrate are removed together with the use of a substitution fluid, continuous arteriovenous hemodiafiltration. We have used CAVHD since 1987 in a medical intensive care unit. Intermittent hemodialysis is no longer used because urea clearance is adequate even in patients with severe catabolism. An initial dialysate rate of 1600 ml/hr is used. Electrolyte and glucose levels should be monitored frequently. Bleeding complications (10%) and catheter-related infection (5%) occur infrequently. An overview of the CAVHD technique is presented as well as guidelines regarding technical and nursing observations for patients receiving CAVHD treatment.