title: Influence of caudal traction of ipsilateral arm on ultrasound image for supraclavicular central venous catheterization.
abstract: BACKGROUND
  The first step for successful ultrasound (US)-guided subclavian vein (SCV) catheterization using a supraclavicular approach is to obtain a good longitudinal image of SCV for in-plane needle placement. We evaluated the efficacy of caudal traction of ipsilateral arm on the exposure of the SCV.
  
  
  METHODS
  We enrolled 20 infants, 20 children, and 20 adults undergoing general anesthesia. After tracheal intubation, US probe was applied as the supraclavicular approach, and the longitudinal US image of SCV was obtained in 3 different ipsilateral arm positions: neutral, caudal traction, and abduction. The length of puncturable SCV, the diameter of SCV, and the available angle for needle insertion in 3 different arm positions were analyzed.
  
  
  RESULTS
  In all patients, the length of puncturable SCV and the available angle for needle insertion were significantly increased after caudal traction (35.6% ± 27.1% and 25.0% ± 19.3%, respectively) and decreased after the abduction (36.6% ± 22.9% and 29.5% ± 23.8%, respectively) compared to neutral position. The diameter of SCV was not changed after applying the caudal traction in infants and children. However, in adults, the caudal traction slightly increased the diameter of SCV (P = .012).
  
  
  CONCLUSIONS
  The caudal traction of ipsilateral arm toward to the knee improves the longitudinal US view of SCV for the supraclavicular approach, without reducing its size. Proper caudal traction of the arm might ensure the high success rate with safe needle insertion technique. Abduction should be avoided during US-guided supraclavicular SCV catheterization.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Eun-Hee
authors.initials: EH
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: In-Kyung
authors.initials: IK
authors.lastname: Song
authors.affiliation: Department of Anesthesiology and Pain Medicine, Keimyung University Dongsan Medical Center, Daegu, Republic of Korea.
authors.forename: Hyun-Chang
authors.initials: HC
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Hee-Soo
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Republic of Korea. Electronic address: jintae73@snu.ac.kr.
authors.forename: Jin-Tae
authors.initials: JT
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D001132:Arm; D002405:Catheterization, Central Venous / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D056888:Patient Positioning / Q000379:methods*; D011446:Prospective Studies; D013350:Subclavian Vein / Q000000981:diagnostic imaging*; D014143:Traction; D018084:Ultrasonography, Interventional / Q000379:methods*