title: Arteriovenous fistula cannulation by buttonhole technique using dull needle.
abstract: BACKGROUND
  Cannulation of arteriovenous fistula (AVF) may be performed by the following techniques: area puncture, rope ladder, or buttonhole. The ideal technique has not yet been established.
  
  
  OBJECTIVE
  To assess the complications and difficulties of introducing the buttonhole (BH) technique for cannulation of AVF created with a native vein in a dialysis unit.
  
  
  METHODS
  Sixteen patients (mean age, 57 ± 14 years) undergoing hemodialysis for 63 ± 38 months were changed to BH AVF cannulation. In the phase of track formation cannulations were performed with sharp needles and, in the maintenance phase, with blunt needles. In both phases, patients were assessed for pain intensity on a 0 to 10 scale.
  
  
  RESULTS
  The number of HD sessions required for the track formation was 9.5 ± 1.5 and the number of sessions during the maintenance phase was 29.7 ± 0.8 per patient. During the 152 HD for the track formation, no significant complications occurred. During the 475 HD sessions using the BH technique and a blunt needle, the complications were as follows: resistance to cannulation (7.6%); cannulation using a sharp needle due to cannulator choice (5.7%); change from a blunt to a sharp needle during cannulation (4.2%); and local bleeding (0.8%). One patient required antibiotic therapy. The median pain intensity reported by the patients was four during the track formation, and two during cannulation with a blunt needle. The Kt/V values before and after changing the cannulation technique did not differ (1.48 ± 0.27 and 1.48 ± 0.23).
  
  
  CONCLUSIONS
  The introduction of the BH technique with a blunt needle is technically easy, has few complications, reduces pain, and does not induce change in dialysis dose.
authors.affiliation: Instituto de Nefrologia de Taubaté, São Paulo, Brazil. dr.martinscastro@uol.com.br
authors.forename: Manuel Carlos Martins de
authors.initials: MC
authors.lastname: Castro
authors.forename: Celina de Fátima e
authors.initials: Cde F
authors.lastname: Silva
authors.forename: João Marcos Rodrigues de
authors.initials: JM
authors.lastname: Souza
authors.forename: Maria Cristina Silva Brotero de
authors.initials: MC
authors.lastname: Assis
authors.forename: Maria Valéria da Silva
authors.initials: MV
authors.lastname: Aoki
authors.forename: Magdaleni
authors.initials: M
authors.lastname: Xagoraris
authors.forename: Jerônimo Ruiz
authors.initials: JR
authors.lastname: Centeno
authors.forename: José Adilson Camargo de
authors.initials: JA
authors.lastname: Souza
mesh_terms: D001166:Arteriovenous Shunt, Surgical / Q000295:instrumentation / Q000379:methods*; D002404:Catheterization / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009339:Needles; D006435:Renal Dialysis