In adults and children, current guidelines recommend measuring the diameter of the vein before the insertion of central catheters, in order to match vein diameter with catheter caliber and thus reduce the risk of venous thrombosis.
In the neonatal intensive care unit, central catheters are often used but the vein diameter is usually not considered.
In this study, the authors assessed the diameter of the most relevant deep veins in 100 newborns ( mean gestational age of studied infants was 32 weeks and mean weight was 1,690 g. ), using a strict protocol of ultrasound evaluation.
The results in this study are: The mean diameter of the brachiocephalic vein was consistently ≥3 mm, with no significant difference between the right and the left side. The femoral vein diameter, on the other hand, was considerably smaller than 3 mm for infants with a weight <2.000g. Interobserver repeatability was found to be very high.

Their conclusion is : Preprocedural ultrasound scan of veins is feasible and easy, also in newborns, and it should be recommended for optimizing central venous catheterization.

Authors : Giovanni Baronea Vito D’Andreaa Giovanni Ventoa Mauro Pittirutib
a Neonatal Intensive Care Unit, Fondazione Policlinico A. Gemelli IRCSS, Rome, Italy;
b Department of Surgery, Fondazione Policlinico A. Gemelli IRCSS, Rome, Italy

Neonatology 2019;115:335–340