The effect of lying position on the location depth and cross-sectional area of internal jugular vein

Objective To investigate the effects of the site for access to internal jugular vein (lateral versus anterior),lying position of patients (supine versus Trendelenburg),and head rotation (0°,20°,and maximum) during central venous catheterization on the location depth and cross-sectional area (CSA) of the right internal jugular vein (IJV).Methods Fifteen healthy volunteers were recruited in this prospective observational study from September 2008 to October 2008.Healthy volunteers were placed in flat supine position and 15°.Trendelenburg position separately.In each position,IJV were measured ultrasonographically from lateral site and anterior site with the head oriented at 0°,20°,and maximum rotation separately.Data of measured CSA and location depth of internal jugular vein in different positions were compared.Results The largest CSA (2.16 ±0.89) cm2 and location depth [(1.38 ± 0.43)cm] were occurred at the lateral approach in Trendelenburg position with head oriented at maximum rotation.The CSA in Trendelenburg position was larger than that in flat supine position.Only at the maximum head rotation,lateral approach got statistically larger CSA.The effects of head rotation varied with different degrees of rotation.Conclusions Site of approach,lying position and head rotation had noticeable effects on internal jugular vein cross-sectional area.Trendelenburg position increased the CSA of IJV. Key words: Jugular veins;  Posture;  Ultrasonography ;  Trendelenburg position;  Supine Position; Area;  Human volunteers;  Central venous catheterization