title: Valsalva and gravitational variability of the internal jugular vein and common femoral vein: ultrasound assessment.
abstract: OBJECTIVE
  Central venous cannulation via the common femoral vein is an important starting point for many interventions. The purpose of this study was to determine the optimum conditions for cannulation of the femoral vein and to compare these with the relative changes in the internal jugular vein.
  
  
  METHODS
  High-resolution 2D ultrasound was utilised to determine variability of the calibre of the femoral and internal jugular veins in 10 healthy subjects. Venous diameter was assessed during the Valsalva manoeuvre and in different degrees of the Trendelenburg position.
  
  
  RESULTS
  The Valsalva manoeuvre significantly increased the size of the femoral and internal jugular veins. There was a relatively greater increase in femoral vein diameter when compared with the internal jugular vein of 40 and 29%, respectively. Changes in body inclination (Trendelenburg position) did not significantly alter the luminal diameter of the femoral vein. However, it significantly increased internal jugular vein diameter.
  
  
  CONCLUSIONS
  Femoral vein cannulation is augmented by the Valsalva manoeuvre but not significantly altered by the gravitational position of the subject.
authors.affiliation: Department of Radiology, The Adelaide and Meath Hospital, Tallaght, Dublin 24, Ireland. pbeddy@eircom.net
authors.forename: P
authors.initials: P
authors.lastname: Beddy
authors.forename: T
authors.initials: T
authors.lastname: Geoghegan
authors.forename: N
authors.initials: N
authors.lastname: Ramesh
authors.forename: O
authors.initials: O
authors.lastname: Buckley
authors.forename: J
authors.initials: J
authors.lastname: O'Brien
authors.forename: J
authors.initials: J
authors.lastname: Colville
authors.forename: W C
authors.initials: WC
authors.lastname: Torreggiani
mesh_terms: D000328:Adult; D002405:Catheterization, Central Venous / Q000379:methods; D005260:Female; D005268:Femoral Vein / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D006112:Gravitation; D018475:Head-Down Tilt / Q000502:physiology*; D006801:Humans; D007601:Jugular Veins / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008297:Male; D012016:Reference Values; D018608:Ultrasonography, Doppler / Q000379:methods; D014636:Valsalva Maneuver / Q000502:physiology*; D014664:Vasodilation / Q000502:physiology