title: A quantitative analysis of the relation between the clavicular tilt angle and subclavian central venous catheter misplacement.
abstract: OBJECTIVE
  The aim of the present study was to investigate the relation between shoulder position and subclavian central venous (SCV) catheter misplacement. The shoulder position was estimated using clavicular tilt angle (CTA) values observed on anteroposterior chest X-ray images.
  
  
  METHODS
  A retrospective case-control study was conducted on all adult patients who underwent SCV catheterization in the emergency department during a 12-month period. Collected data included patient age, sex, diagnosis, catheterization side, catheter misplacement, and physician's level of experience in catheterization. The CTA and other radiological variables such as the ipsilateral transverse length of the thorax and thickness of the clavicle were investigated.
  
  
  RESULTS
  Among all central venous catheterizations (n=1,599), the subclavian route was used 981 times (61.4%). There were 51 misplacements of SCV catheters (5.2%) during the study period. There were no differences in the sex, age, blood pressure, and diagnosis between the two groups. The CTA values were 28.5°±7.3° and 22.6°±6.3° in the misplacement group and control group, respectively (95% confidence interval, 3.6 to 8.1; P<0.001).
  
  
  CONCLUSIONS
  In this study, the CTA was found to be 5.9° larger in the misplacement group than in the control group. Assuming that CTA indicates the shoulder position, our findings suggest that the chance of SCV catheter misplacement may be reduced by avoiding the shoulder elevated.
authors.affiliation: Department of Emergency Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Hoe-Hwan
authors.initials: HH
authors.lastname: Jeong
authors.affiliation: Department of Emergency Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Jung-Hoon
authors.initials: JH
authors.lastname: Yoon
authors.affiliation: Daegu Research Center for Medical Device and Green Energy, Korea Institute of Machinery & Materials, Daegu, Korea.
authors.forename: Sungho
authors.initials: S
authors.lastname: Oh
authors.affiliation: Department of Radiology, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Je Hwan
authors.initials: JH
authors.lastname: Won
authors.affiliation: Department of Emergency Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Young-Gi
authors.initials: YG
authors.lastname: Min
authors.affiliation: Department of Anesthesiology, University of Florida College of Medicine, Gainesville, FL, USA.
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Gravenstein
authors.affiliation: Department of Emergency Medicine, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Sang-Cheon
authors.initials: SC
authors.lastname: Choi
keywords: Catheterization; Clavicle; Radiography; Subclavian vein; Treatment failure