Increased use of brachiocephalic arteriovenous fistulas improves functional primary patency.

OBJECTIVE: As vascular surgeons strive to meet the Fistula First Initiative, some authors have observed a decrease in arteriovenous fistula (AVF) maturation rates in association with an increase in AVF creation. In May 2012, we adopted a practice change in an attempt to maintain the same high level of AVF creation while leading to a decrease in fistula failures. METHODS: A retrospective study was conducted of all dialysis access procedures performed by a single vascular surgeon before (period 1; before May 1, 2012) and after (period 2; after May 1, 2012) the change in practice pattern. The adopted change included favoring the brachiocephalic location unless the patient was an ideal anatomic candidate for a radiocephalic AVF, creating a larger and standardized arteriotomy, and using a large venous footplate whenever possible. The main outcome measure was primary functional patency at 1 year. Secondary outcome measures included primary patency at 1 year, time to maturation, type of fistula created, steal syndrome, and tunneled hemodialysis catheter infections. RESULTS: Of 213 vascular access procedures performed, 191 (90%) were AVFs. There was no difference in use of AVFs between period 1 (93% AVFs) and period 2 (88% AVFs; P = .2). Use of brachiocephalic AVFs increased from 38% in period 1 to 56% in period 2 (P = .01), with a corresponding trend toward a decrease in radiocephalic AVFs in period 2 (36% in period 1 to 27% in period 2; P = .2). Primary functional patency at 1 year was 47% in period 1 and 63% in period 2 (P = .03). Primary patency at 1 year was 51% in period 1 and 70% in period 2 (P = .001). Time to reach functional maturation was decreased in period 2 (median, 76 vs 82.5 days; P = .046). There was no difference in steal syndrome (P = 1.0), and the incidence of hemodialysis catheter infections was lower in period 2 (0 vs 7 [7%]; P = .006). CONCLUSIONS: Increasing brachiocephalic AVF creation and reducing our reliance on radiocephalic AVFs resulted in a significant increase in primary functional patency at 1 year. This was achieved while maintaining the same high percentage of fistulas, a lower rate of central catheter infections, and the same low incidence of steal syndrome.

Variation in the learning curves of general surgery residents performing arteriovenous fistulas.

BACKGROUND: An arteriovenous fistula (AVF), performed for hemodialysis access, provides one of the few remaining opportunities for general surgery residents to perform an open vascular anastomosis (VA). Limited data exist regarding the learning curve of residents performing this procedure. The objective of this study was to determine how residents improve in performance of VA by implementing real-time tracking of anastomosis time as well as technical errors. STUDY DESIGN: From April 2012 to January 2014, we conducted a prospective intraoperative assessment of 9 postgraduate year 3 general surgery residents during the performance of AVFs using a checklist of common errors in VA. Time for AVF anastomosis completion and number and types of technical errors during anastomosis were recorded. Primary end points were the change in anastomosis time and change in technical errors over time. RESULTS: A total of 86 AVFs were performed and assessed intraoperatively. Each resident performed a median of 10 AVFs (interquartile range [IQR]: 7-11). The mean anastomosis time was 18.1 minutes. The mean number of technical errors was 13.8 per case. Overall, for every additional AVF performed, mean anastomosis time decreased by 0.63 minutes (95% CI: 0.45-0.81, p < 0.0001) and the mean number of technical errors decreased by 1.0 (95% CI: 0.7-1.3, p < 0.0001). The greatest improvement in overall errors (mean difference = 7.9, p = 0.03) and time (mean difference = 4.7min, p = 0.03) occurred after the performance of 3 AVFs. However, when analyzed by individual resident, the R(2) value for anastomotic time by number of AVFs performed ranged from 0.01 to 0.69. Similarly, for technical errors, the R(2) value by number of AVFs performed ranged from 0.04 to 0.62. CONCLUSIONS: In novice surgical residents performing AVFs, improvement in VA skill can readily be tracked via anastomosis time and technical errors. Collectively, there is a strong association between number of cases performed and reduction in time and errors. However, individually, the number of cases completed did not correlate well with time and errors. These findings suggest that for VA skills, determining progression from novice to competence cannot rely on case volume but rather needs to be individualized.

A prospective randomized study assessing optimal method for teaching vascular anastomoses.

BACKGROUND: Laboratory skills training is now required for general surgery residents. The optimal method of teaching vascular anastomosis (VA) is not well defined. Teaching VA skills one-on-one with a faculty instructor will result in a more rapid accumulation of skills than teaching in a large group setting. METHODS: Residents were shown an instructional video on how to perform a VA using a standardized model (cadaver saphenous vein and porcine aorta). Each resident then performed a baseline VA. Sixteen first- and second-year surgical residents were then randomized to 2 VA teaching sessions that consisted of either 1) group teaching (GT, 8 residents in a room with 1 faculty instructor circulating) or 2) one-on-one teaching (1-on-1, faculty member focused on individual resident). After each of these sessions, residents performed a standardized VA. The anastomoses were video recorded. Performance was evaluated using a standardized scoring system by a separate expert who viewed the video recordings in a blinded fashion. Outcome measures included total errors, total time, global rating scale, and an anastomosis-specific end-product evaluation (leak and passage of coronary dilator). RESULTS: Overall, significant decreases in total errors (21 to 15, P=0.001) and time to complete anastomoses (42 to 38 min, P=0.02) and an increase in global rating scales (7 to 11, P=0.003) were noted in both groups from baseline after 2 VA teaching session. The 1-on-1 group demonstrated significantly greater improvement in terms of reduced anastomotic time (30 vs. 42 min, P=0.007) and in reduction of errors (13 vs. 19 errors, P=0.09) than the GT group. CONCLUSIONS: The high-fidelity VA model is a useful tool for junior general surgery residents. Both GT and 1-on-1 groups demonstrated significant improvement in total errors and time after only 2 sessions. Greater improvement was noted using the 1-on-1 model.