Microsurgery – AVF, Pierre Bourquelot 11/04/2006

Distal arteriovenous fistula creation involves dissection and suture of small calibre vessels, on which surgical traumatism must be reduced as much as possible so as to prevent early and late thrombosis. No-touch microsurgical technique is mandatory to reduce vessels injury. Preventive hemostasis using a pneumatic tourniquet makes extensive arterial dissection for clamping unnecessary: arterial spasm and lesions induced by arterial dissection are avoided. When hemostasis is incomplete, atraumatic micro-clamps are placed on the artery after minimal dissection. Side to end arteriovenous anastomosis (limiting venous dissection and facilitating the proximal part of the anastomosis) is used by most surgeons, since the first description of side to side fistula by Brescia et al. Operating microscope is routinely used, not only for children. The major rule for “no-touch” microsurgical suturing is that forceps must never grasp the intima. The thinnest possible needles are used (8.0 to 11.0 monofilament sutures). Intraluminal heparinized saline injection and any vessels dilation are prohibited. Systemic anticoagulation is necessary in hypercoagulation conditions (nephrotic syndrome mainly). These recommendations allow for good postoperative and long-term results even in small calibre vessels (Figure I). In adults we observe frequently distal arteriovenous fistulas which remained patent for more than 25 years.

Figure 1