Purpose: The Dialysis Outcome Quality Initiative (DOQI) guidelines recommend that arteriovenous fistulas (AVF) be constructed in at least 50% of hemodialysis access procedures. Preoperative duplex ultrasound (US) scanning and venography may increase options for AVF with identification of veins that are not clinically evident. However, maturation of autogenous fistulas created on the basis of findings at duplex US scanning and venography has not been carefully examined.
Methods: From January 1999 to July 2002, 256 new hemodialysis access procedures were performed in 202 patients in an academic tertiary care center. If physical examination failed to disclose adequate vessels for hemodialysis access, patients underwent duplex US scanning mapping. Venography was performed when no usable vein or only a basilic vein was identified at duplex US scanning. Functional maturation rate and mean maturation time (time from fistula creation to initiation of hemodialysis) were determined. This experience was compared with that in a group of 128 patients in whom 148 hemodialysis access fistulas were created before we implemented liberal use of preoperative duplex US scanning and venography (January 1997-December 1998).
Results: From January 1999 to July 2002, preoperative duplex US scanning was performed in 68% of patients, and venography in 32% of patients. Autogenous fistula creation rate increased from 61% to 73% in all patients with hemodialysis access fistulas (P =.15) and from 66% to 83% in patients undergoing a first access procedure (P <.05). The use of basilic vein transposition also increased, from 3% in the earlier period to 13% in the later period (P <.05). Mean maturation time for arteriovenous fistulas was 70 days. Functional maturation rate decreased from 73% to 57% (P <.05) after implementation of preoperative imaging and more aggressive vein use.
Conclusion: Implementation of preoperative duplex US scanning and venography as a component of a more aggressive protocol to create native fistulas was pivotal in exceeding DOQI guidelines for hemodialysis access. However, this approach resulted in the unintended sequela of decreased fistula maturation rate. Our experience suggests that improved selection criteria based on findings at preoperative imaging are needed to further refine and optimize arteriovenous access surgery.