title: Transient ulnar artery compression facilitates transradial access.
abstract: BACKGROUND
  Unsuccessful radial artery puncture is one of the important causes of transradial procedure failure. Ulnar artery compression made the radial artery pulse stronger. Whether it would make transradial access easier, however, is uncertain.
  
  
  METHODS
  A prospective randomized controlled trial was conducted among 446 patients who planned for transradial cardiac catheterization. Patients were randomized to receiving either transient ulnar artery compression (UC) or standard treatment (standard) for half an hour prior to needle insertion (217 UC, 229 standard). The diameters of right radial artery and ulnar artery were measured by ultrasound on admission and before artery puncture. Primary endpoints included the number of attempts to access, the rate of first-pass success, and time for a successful access. Secondary endpoints were the number of difficult procedures, and the incidence of puncture failure.
  
  
  RESULTS
  The diameters of radial artery were larger after half an hour's ulnar artery compression, but there were no obvious changes in that of ulnar artery. As compared with standard group, the number of attempts was significantly decreased (1.42 ± 1.10 vs 2.97 ± 2.38, P <0.001), and the rate of first-pass success was greatly enhanced (73.27% vs 57.64%, P <0.001) in UC group. Meanwhile, the time for access was decreased (59 ± 15 seconds vs 71 ± 18 seconds, P <0.001) with UC. In addition, the proportion of difficult procedures of UC group was less than that of standard group (4.61% vs 10.92%, P = 0.013). No significant differences were found in failure rates of sheath insertion and puncture between the 2 groups.
  
  
  CONCLUSIONS
  Transient ulnar artery compression enhances the efficacy and feasibility of radial artery intubatton in transradial catheterization.
authors.affiliation: Department of Cardiology, Beijing An Zhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Disease, The Key Laboratory of Remodeling-related Cardiovascular Disease, Ministry of Education, Beijing, China.
authors.forename: Zhi-Ming
authors.initials: ZM
authors.lastname: Zhou
authors.forename: Zhen-Xian
authors.initials: ZX
authors.lastname: Yan
authors.forename: Bin
authors.initials: B
authors.lastname: Nie
authors.forename: Yong-He
authors.initials: YH
authors.lastname: Guo
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Zhou
mesh_terms: D006328:Cardiac Catheterization; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011312:Pressure; D011446:Prospective Studies; D011677:Punctures; D017534:Radial Artery / Q000601:surgery*; D017535:Ulnar Artery