Placement of umbilical venous catheters with use of bedside real-time ultrasonography.

Real-time ultrasonography was used to assess the position of umbilical venous catheters tips in 79 newborn infants (birth weight range, 400 to 4200 gm). The position of the umbilical venous catheters determined by ultrasonography was compared with the projection of the catheter tip on the closest vertebral body shown on a standard chest radiograph. Of the catheters initially placed with radiographic guidance, 56% were repositioned because of unsatisfactory location. Ultrasonography is more precise than radiography because it allows direct visualization of the catheter tips in relation to internal vascular structures. When ultrasonography is unavailable, placement at the ninth thoracic vertebral body ensures safe positioning.