The role of regional vs general anesthesia on arteriovenous fistula and graft outcomes: a single institution experience and literature review

Abstract Introduction Multiple studies have demonstrated the benefits of creating arteriovenous fistulas (AVFs) under regional anesthesia. This is most likely due to the avoidance of hemodynamic instability and stress response of general anesthesia as well as the sympathectomy associated with brachial plexus blockade. Since vein diameter is the major limiting factor for primary AVFs creation and maturation, our aim is to investigate if the vasodilation that accompanies regional anesthesia leads to improved patency and maturation rate of autologous AVF and graft (AVG) patency compared to those placed under general anesthesia. Methods This retrospective study was approved by the Institutional Review Board. 238 patients that had either an AVF or an arteriovenous graft placed at Mayo Clinic Florida between 2012 and 2017 were analyzed. Demographics, access type, preoperative vein diameter, anesthesia type, change of plan after regional vs general anesthesia, and outcomes were assessed. All statistical tests were two-sided with the alpha level set at 0.05 for statistical significance. Results Among 238 patients, 120 (50.4%) patients underwent regional anesthesia. Difference between the two groups in risk factors, and 30-day or long-term outcomes (failure, abandonment, or reoperation) were not statistically significant. 58.5% of accesses placed under general anesthesia were abandoned compared to 45.2% of those placed under regional anesthesia. 25.8% of accesses placed under general anesthesia were abandoned due to loss of patency compared to 19.2% of those placed under regional anesthesia. Two-month failure was higher in the general anesthesia group compared to the regional anesthesia group (p=0.076). Following preoperative vein mapping, 22 patients were originally intended to have an arteriovenous graft placed under regional anesthesia. Following brachial plexus blockade, 9 of these patients (9/22: 41%) were successfully switched to AVF, while the other 13 followed the original surgical plan and received an AVG. Of these, 0 failed and 0 were abandoned due to loss of patency. Conclusions This study showed possible improvement in failure rates for vascular accesses placed under regional anesthesia compared to those placed under general anesthesia. Additionally, we showed an impact of regional anesthesia on the surgical plan by transitioning from a planned AVG to an AVF, intraoperatively. Giving patients with originally inadequate vein diameter the chance to have the preferred hemodialysis access method by simply switching anesthesia type could reduce the number of grafts placed in favor of fistulas.