Outcomes of post-operative duplex ultrasound following arteriovenous fistula formation: A pragmatic single-centre experience.

Background: Duplex ultrasound surveillance with pre-emptive treatment of an identified stenosis is increasingly being utilised to help maintain arteriovenous fistula patency. This study aims to determine whether post-operative duplex ultrasound surveillance can improve fistula patency at 12 months and improve the proportion of 'pre-haemodialysis' patients commencing haemodialysis via a usable fistula.

Methods: All arteriovenous fistulae formed between 1st January 2015 and 31st August 2017 in a single, tertiary vascular centre were included. Primary and secondary patency at 12 months, along with the proportion of pre-haemodialysis patients commencing haemodialysis via a usable arteriovenous fistula, were compared between the fistulae undergoing duplex ultrasound surveillance and 'standard practice'.

Results: Two hundred forty-one arteriovenous fistulae were created in 216 patients. A higher proportion of brachiobasilic transposition arteriovenous fistula and patients undergoing arteriovenous fistula creation following a previously failed access were identified in the duplex ultrasound surveillance group. Primary patency at 12 months (hazard ratio = 0.43, 95% confidence interval = 0.30-0.61, p < .001) was significantly lower in the duplex ultrasound surveillance group compared with the 'standard practice' group. Despite this, no difference was identified in secondary patency at 12 months (hazard ratio = 1.82, 95% confidence interval = 0.87-3.80, p = .112). No difference was also identified in the proportion of pre-haemodialysis patients starting haemodialysis with a usable arteriovenous fistula (duplex ultrasound surveillance = 65.0% vs standard practice = 77.8%; odds ratio = 0.53, 95% confidence interval 0.58-1.19, p = .279).

Conclusion: Post-operative duplex ultrasound surveillance following arteriovenous fistula formation is associated with higher rates of post-operative intervention; however, this does not translate into improved secondary patency or the proportion of pre-haemodialysis patients commencing HD via their fistula.