In most critically ill unstable patients, continuous arteriovenous hemofiltration (CAVH) and continuous arteriovenous hemofiltration with dialysis (CAVHD) offer significant advantages over dialysis and ultrafiltration. Improvements in CAVH methodology have occurred since its introduction, but an ideal vascular access has yet to be designed. Scribner shunts may result in loss of a future access site, while femoral artery and vein catheterization render the patient immobilized. We have developed a percutaneous external arteriovenous femoral shunt to overcome this difficulty. The catheter consists of two single-lumen flexible polyurethane catheters with a subcutaneous Dacron cuff. A percutaneous Seldinger technique is used with a peel-away sheath to insert one catheter in the artery and one in the vein. To minimize infection and ensure durability, a 10-cm tunnel is created so that the exit of the catheters on the upper thigh is away from the groin. Like the Scribner shunt, a connecting tube is used between the catheters to maintain the patency when the shunt is not in use. Our experience with this technique is limited to seven treatments in seven patients (five CAVH, two CAVHD). Good blood flow (average, 80 mL/min), ultrafiltration rate (7 mL/min), and biochemical studies demonstrated the efficiency of the access. The average treatment was 10 days and patients were allowed to do moderate movement without resulting thrombosis or infection of the access. The major advantages of this new and efficient access for CAVH and CAVHD include simple introduction by a nephrologist, lack of potential serious complications, avoidance of sacrifice of major vessels, early ambulation and movement without compromising function, and a design for prolonged usage. © 1990, National Kidney Foundation Inc.. All rights reserved.
