title: Effect of brachial plexus block-driven vascular access planning on primary distal arteriovenous fistula recruitment and outcomes.
abstract: OBJECTIVE
  Hemodialysis vascular accesses (VAs) are traditionally planned based on the nondominant upper extremity preoperative physical and sonographic vascular findings. Clinical guidelines advocate the use of the most suitably distended vein in the most distal location. Brachial plexus block (BPB), through its sympathectomy-like effect, promotes vasodilation and can thus further optimize vein recruitment and operative strategy. However, studies on its role in driving primary distal autogenous arteriovenous fistula (AVF) placement are limited. We therefore evaluated a traditional approach of clinic-based VA planning against an on-table sonography-guided strategy under BPB.
  
  
  METHODS
  This was a prospective observational study involving 110 consecutive end-stage renal disease multiethnic Asian patients referred for primary VA creation under BPB after preoperative venous mapping. Cases were grouped according to whether there was a preset operative plan for radial cephalic (RC) or brachial cephalic (BC) AVF creation based on artery and vein >2 mm and >2.5 mm size criteria respectively (group A) or vein size or length were suboptimal (2-2.5 mm and <5 cm respectively), thus precluding any operative plan till after BPB (group B). Group B also included cases with a preset VA plan but that subsequently underwent an on-table change in operative plan as a result of more favorable distal vein dilation post-BPB. RC AVF recruitment, maturation, and patency rates were compared in the two groups over a 1-year follow up.
  
  
  RESULTS
  One hundred RC and BC AVF were available for analysis after excluding brachial AVFs and grafts: 41 in group A and 59 in group B. Twenty one (51%) primary RC AVFs were created according to a preset preoperative plan compared with 37 (63%) based upon on-table planning or plan modification (P > .05). Satisfactory post-BPB forearm vasodilation resulted in 44% of 36 plans for BC being changed to RC AVFs. RC AVF 6-week hemodynamic maturation and 3-month functional maturation in group A vs B were 48% vs 60% and 69% vs 57%, respectively (P > .05). One-year primary and secondary patency rates were 57% vs 50% and 73% vs 87%, respectively (log rank >.05). Outcomes of RC AVFs in group B were not inferior to those of BC AVFs.
  
  
  CONCLUSIONS
  On-table BPB-driven VA planning and plan modification strategy contribute to considerable AVF recruitment but do not lead to significantly better distal AVF prevalence or outcomes over the traditional approach. An adequately powered randomized controlled study is, however, warranted to better assess the long-term clinical and cost benefits of such a strategy.
authors.affiliation: Division of Nephrology, Department of General Medicine, Khoo Teck Puat Hospital, Alexandra Health, Singapore. Electronic address: claude.jeffrey.renaud@alexandrahealth.com.sg.
authors.forename: Claude J
authors.initials: CJ
authors.lastname: Renaud
authors.affiliation: Division of Vascular Surgery, Department of General Surgery, Khoo Teck Puat Hospital, Alexandra Health, Singapore.
authors.forename: Chuo Ren
authors.initials: CR
authors.lastname: Leong
authors.affiliation: Department of Anesthesia, Khoo Teck Puat Hospital, Alexandra Health, Singapore.
authors.forename: Hsien Wern
authors.initials: HW
authors.lastname: Bin
authors.affiliation: Division of Vascular Surgery, Department of General Surgery, Khoo Teck Puat Hospital, Alexandra Health, Singapore.
authors.forename: Julian Chi Leung
authors.initials: JC
authors.lastname: Wong
mesh_terms: D000368:Aged; D001166:Arteriovenous Shunt, Surgical / Q000009:adverse effects; D044466:Asian People; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D065527:Brachial Plexus Block / Q000009:adverse effects; D004108:Dilatation, Pathologic; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000175:diagnosis / Q000208:ethnology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D017534:Radial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D006435:Renal Dialysis; D012846:Singapore / Q000453:epidemiology; D013997:Time Factors; D016896:Treatment Outcome; D018616:Ultrasonography, Doppler, Duplex; D018084:Ultrasonography, Interventional; D034941:Upper Extremity / Q000098:blood supply*; D014654:Vascular Patency; D014680:Veins / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*