Variability in anesthetic considerations for arteriovenous fistula creation

Anesthetic options for arteriovenous fistula (AVF) creation include regional anesthesia (RA), general anesthesia (GA) and local anesthetic for select cases. In addition to the benefits of avoiding GA in high-risk patients, recent studies suggest that RA may increase perioperative venous dilation and improve maturation. Our objective was to assess perioperative outcomes of AVF creation with respect to anesthetic modality and identify patient-level factors associated with variation in contemporary anesthetic selection.

National Surgical Quality Improvement Project (NSQIP) data (2007-2010) were accessed to identify patients undergoing AVF creation. Univariate analysis and multivariate logistic regression were performed to assess the relationships among patient characteristics, anesthesia modality and outcome.

Of 1,540 patients undergoing new upper extremity AVF creation, 52% were male and 81% were younger than 75 years. Anesthesia distribution was GA in 85.2%, local/monitored anesthetic care (MAC) in 2.9% and RA in 11.9% of cases. By multivariate analysis, independent predictors of RA were dyspnea at rest (hazard ratio [HR] 2.3, 95% confidence interval [CI] 1.1-4.9), age >75 (HR 1.6, 95% CI 1.1-2.3) and teaching hospital status as indicated by housestaff involvement (HR 3.7, 95% CI 2.5-5.5). RA was associated with higher total operative time, duration of anesthesia, length of time in operating room and duration of anesthesia start until surgery start (p<0.01). There were no differences between perioperative complications or mortality among anesthetic modalities, although all deaths occurred in the GA group.

Despite recent reports highlighting potential benefits of RA for AVF creation, GA was surprisingly used in the vast majority of cases in the United States. The only comorbidities associated with preferential RA use were advanced age and dyspnea at rest. Practice environment may influence anesthetic selection for these cases, as a nonteaching environment was associated with GA use. The trend seen here toward higher mortality in GA and the potential perioperative benefits of RA for the access should encourage more widespread use of RA in practice for this high-risk patient population.