title: Efficacy of ultrasound-guided radial artery catheterization: a systematic review and meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  Ultrasound guidance has emerged as an adjunct for central vein catheterization in both adults and children. However, the use of ultrasound guidance for radial arterial catheterization has not been well established. We conducted a systematic review and meta-analysis to evaluate the efficacy of ultrasound guidance for radial artery catheterization.
  
  
  METHODS
  PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched. Randomized controlled trials (RCTs) comparing ultrasound guidance with other techniques (palpation or Doppler) in adult or pediatric patients requiring radial artery catheterization were included. The primary outcome was first-attempt success.
  
  
  RESULTS
  Seven RCTs enrolling 546 patients met the inclusion criteria, and all the selected trials were considered as at high risk of bias. Ultrasound-guided radial artery catheterization was associated with an increased first-attempt success (relative risk (RR) 1.55, 95% confidence interval (CI) 1.02 to 2.35). There was significant heterogeneity among the studies (I2 = 74%). Ultrasound-guided radial artery catheterization in small children and infants also provided an increased chance for first-attempt success (RR 1.94, 95% CI 1.31 to 2.88). Ultrasound guidance further significantly reduced mean attempts to success (weighted mean difference (WMD) -1.13, 95% CI -1.58 to -0.69), mean time to success (WMD -72.97 seconds, 95% CI -134.41 to -11.52), and incidence of the complication of hematoma (RR 0.17, 95% CI 0.07 to 0.41).
  
  
  CONCLUSIONS
  Ultrasound guidance is an effective and safe technique for radial artery catheterization, even in small children and infants. However, the results should be interpreted cautiously due to the heterogeneity among the studies.
authors.forename: Wan-Jie
authors.initials: WJ
authors.lastname: Gu
authors.forename: Hong-Tao
authors.initials: HT
authors.lastname: Tie
authors.forename: Jing-Chen
authors.initials: JC
authors.lastname: Liu
authors.forename: Xian-Tao
authors.initials: XT
authors.lastname: Zeng
mesh_terms: D002405:Catheterization, Central Venous / Q000379:methods*; D006801:Humans; D017534:Radial Artery / Q000000981:diagnostic imaging*; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional / Q000379:methods*