title: Ultrasonic locating devices for central venous cannulation: meta-analysis.
abstract: OBJECTIVE
  To assess the evidence for the clinical effectiveness of ultrasound guided central venous cannulation.
  
  
  METHODS
  15 electronic bibliographic databases, covering biomedical, science, social science, health economics, and grey literature.
  
  
  METHODS
  Systematic review and meta-analysis of randomised controlled trials. Populations Patients scheduled for central venous access. INTERVENTION REVIEWED: Guidance using real time two dimensional ultrasonography or Doppler needles and probes compared with the anatomical landmark method of cannulation.
  
  
  METHODS
  Risk of failed catheter placement (primary outcome), risk of complications from placement, risk of failure on first attempt at placement, number of attempts to successful catheterisation, and time (seconds) to successful catheterisation.
  
  
  RESULTS
  18 trials (1646 participants) were identified. Compared with the landmark method, real time two dimensional ultrasound guidance for cannulating the internal jugular vein in adults was associated with a significantly lower failure rate both overall (relative risk 0.14, 95% confidence interval 0.06 to 0.33) and on the first attempt (0.59, 0.39 to 0.88). Limited evidence favoured two dimensional ultrasound guidance for subclavian vein and femoral vein procedures in adults (0.14, 0.04 to 0.57 and 0.29, 0.07 to 1.21, respectively). Three studies in infants confirmed a higher success rate with two dimensional ultrasonography for internal jugular procedures (0.15, 0.03 to 0.64). Doppler guided cannulation of the internal jugular vein in adults was more successful than the landmark method (0.39, 0.17 to 0.92), but the landmark method was more successful for subclavian vein procedures (1.48, 1.03 to 2.14). No significant difference was found between these techniques for cannulation of the internal jugular vein in infants. An indirect comparison of relative risks suggested that two dimensional ultrasonography would be more successful than Doppler guidance for subclavian vein procedures in adults (0.09, 0.02 to 0.38).
  
  
  CONCLUSIONS
  Evidence supports the use of two dimensional ultrasonography for central venous cannulation.
authors.affiliation: School of Health and Related Research, Regent Court, Sheffield S1 4DA. d.hind@shef.ac.uk
authors.forename: Daniel
authors.initials: D
authors.lastname: Hind
authors.forename: Neill
authors.initials: N
authors.lastname: Calvert
authors.forename: Richard
authors.initials: R
authors.lastname: McWilliams
authors.forename: Andrew
authors.initials: A
authors.lastname: Davidson
authors.forename: Suzy
authors.initials: S
authors.lastname: Paisley
authors.forename: Catherine
authors.initials: C
authors.lastname: Beverley
authors.forename: Steven
authors.initials: S
authors.lastname: Thomas
mesh_terms: D000328:Adult; D002405:Catheterization, Central Venous / Q000009:adverse effects / Q000379:methods*; D005268:Femoral Vein; D006801:Humans; D007223:Infant; D007601:Jugular Veins; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D013350:Subclavian Vein; D018608:Ultrasonography, Doppler; D018084:Ultrasonography, Interventional / Q000379:methods*