title: Optimal head rotation and puncture site for internal jugular vein cannulation after laryngeal mask airway insertion.
abstract: BACKGROUND
  We studied the effect of head rotation on the relative position of the right common carotid artery (CCA) and the right internal jugular vein (IJV) in patients with laryngeal mask airway (LMA) insertion to evaluate the accuracy of anatomical landmarks for right IJV cannulation.
  
  
  METHODS
  We simulated needle insertion to the right IJV on sonograms via the central landmark approach and an approach using the external jugular vein, in patients with LMA insertion (n = 50) or endotracheal intubation (E-tube, n = 50). Overlap index and successful simulation rates were measured according to the different degrees of head rotation.
  
  
  RESULTS
  The overlap index between the right CCA and the right IJV increased with greater degrees of head rotation. It was significantly greater in the LMA insertion group than in the E-tube group in the following head rotation positions: neutral, 15° and 45°. The success rate of the simulation was lower in the LMA insertion group than in the E-tube group. In the LMA insertion group, the success rate of the simulation was highest (62%) with the central landmark approach and in the 15° head rotation position.
  
  
  CONCLUSIONS
  In the LMA insertion group, the overlap index increased incrementally with greater head rotation degrees (from neutral to 45°). The central landmark approach and 15° head rotation position appear to be the optimal puncture site and degree of head rotation for right IJV cannulation in patients with LMA insertion.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea.
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Mi Sook
authors.initials: MS
authors.lastname: Gwak
authors.affiliation: Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Soo Joo
authors.initials: SJ
authors.lastname: Choi
authors.affiliation: Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Song
authors.affiliation: Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Myung Hee
authors.initials: MH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000768:Anesthesia, General / Q000379:methods; D017536:Carotid Artery, Common / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D002405:Catheterization, Central Venous / Q000379:methods; D003198:Computer Simulation; D005260:Female; D006257:Head / Q000000981:diagnostic imaging / Q000502:physiology; D006801:Humans; D007601:Jugular Veins / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D017214:Laryngeal Masks; D008297:Male; D008875:Middle Aged; D009339:Needles; D056888:Patient Positioning / Q000379:methods*; D011446:Prospective Studies; D011677:Punctures; D012399:Rotation; D014463:Ultrasonography
keywords: central venous cannulation; jugular veins; laryngeal mask airway; ultrasonography