Caliber of the deep veins of the arm in infants and neonates: The VEEIN study (Vascular Echography Evaluation in Infants and Neonates)

Purpose: Ultrasound-guided peripherally inserted central catheters (PICCs) are increasingly used in children, though their insertion may be limited by the small caliber of the deep veins of the arm. Previous studies have suggested to use age or weight as a guide to the feasibility of PICC insertion. We have planned an observational study with the purpose of identifying the actual feasibility of PICC insertion based on the ultrasound evaluation of the deep veins of the arm in groups of children of different weight range. Methods: We have studied 252 children weighing between 2.5 and 20 kg, divided in five different groups (group 1: 2.5-4 kg; group 2: 4.1-7 kg; group 3: 7.1-10 kg; group 4: 10.1-15 kg; group 5: 15.1-20 kg): the caliber of brachial vein, basilic vein, and cephalic vein at mid-upper arm + the caliber of the axillary vein at the axilla were measured by ultrasound scan. Results: Veins of caliber >3 mm (appropriate for insertion of a 3 Fr non-tunneled PICC) were found at mid-upper arm in no child of group 1 or 2, in 13% of group 3, in 28% of group 4, and in 54% of group 5. An axillary vein >3 mm (appropriate for insertion of a 3 Fr tunneled PICC) were found in 5.8% of group 1, 30.6% of group 2, 67% of group 3, 82% of group 4, and 94% of group 5. Conclusions: The age and the weight of the child have a small role in predicting the caliber of the veins of the arm. Veins should be measured case by case through a proper and systematic ultrasound evaluation; however, the clinician can expect that insertion of a 3 Fr PICC may be feasible in one third of children weighing between 4 and 7 kg, and in most children weighing more than 7 kg, especially if adopting the tunneling technique.