Effects of head rotation on the right internal jugular vein in infants and young children.

We investigated the effects of head rotation on the cross-sectional area of the right internal jugular vein and its relative position to the carotid artery. Eighty-eight subjects were divided into infants and children groups. The cross-sectional area of the right internal jugular vein and the degree of the carotid artery overlap were measured at 0 degrees (neutral), 40 degrees and 80 degrees of head rotation. The cross-sectional area of the right internal jugular vein was significantly larger at 40 degrees and 80 degrees head rotation compared with the neutral position in both infants and children (p < 0.001). As the head was rotated, the percentage overlap of the carotid artery increased significantly (p < 0.001). We suggest that 40 degrees head rotation appears to be optimal for right internal jugular vein cannulation in paediatric patients.