ORIGINAL ARTICLE Revised formula to determine the insertion length of umbilical vein catheters Gerdina H. Verheij & Arjan B. te Pas & Vivianne E. H. J. Smits-Wintjens & Alexandr Šràmek & Frans J. Walther & Enrico Lopriore Received: 20 December 2012 / Accepted: 20 February 2013 / Published online: 16 March 2013 # Springer-Verlag Berlin Heidelberg 2013 Abstract The method of Shukla is commonly used to predict the insertion length of umbilical vein catheters (UVCs) but often leads to over-insertion. Malposition of UVCs can lead to com- plications. In this study, we compared the formula of Shukla, i.e., 3 Â birth weight in kg þ 9 ð Þ 2 = þ 1cm with a revised for- mula, i.e., 3 Â birthweight in kg þ 9 ð Þ 2cm = in determining the insertion length of UVCs. A cohort where the revised formula was used for UVC placement (revised group) was compared with a historical cohort using the conventional formula (Shukla group). We evaluated the position of UVCs stated as the corre- sponding vertebra level with a radiograph of the infant’ s chest and abdomen immediately after insertion in both groups. Posi- tioning of the catheter tip above the ninth or below the tenth thoracic vertebra was considered too high or too low, respec- tively. Median position of 93 UVCs placed according to Shukla was lower (seventh thoracic vertebra, interquartile range (IQR) 6–9) when compared to 92 UVCs placed according to the revised formula (eighth thoracic vertebra (IQR 7–9)). UVCs were more often over-inserted using the Shukla formula (73 %) when compared to the revised formula (54 %). One UVC in the Shukla group (1 %) and two UVCs in the revised group (2 %) were placed too low (p =NS). Conclusion: The revised formula reduces the rate of over-insertion of UVCs without increasing the rate of inadequate lower positioning. Keywords Umbilical catheter . Central venous catheter . Neonate . Infant Introduction Umbilical vein catheters (UVCs) are frequently required in the management of ill neonates for intravenous administration of parenteral nutrition, hypertonic solutions, blood products, and medication. However, the advantages of UVCs must be care- fully balanced against the potential risks. Several life- threatening complications have been associated with the use of UVCs including catheter-related infections, thrombosis, intestinal perforation, hepatic necrosis, cardiac arrhythmias, myocardial perforation, and pericardial effusion [2–5, 13, 25]. Complications associated with umbilical catheterization often result from inappropriate positioning of the catheter [2, 11, 17]. Accurate prediction of the insertion length of the catheter is therefore paramount, as well as confirmation of the position after insertion by chest X-ray or with ultrasound [14, 16, 24]. Several formulas and graphs using various body measure- ments have been proposed to predict the correct position of umbilical catheters [3, 8, 22]. One of the most common used methods is the formula of Shukla [22]. This method uses equations based on the birth weight of the neonate. In a recent study, we found that the Shukla method was frequently asso- ciated with over-insertion of UVCs [26]. This prompted us to revise the formula and stopped adding 1 cm to the equation as suggested by Anderson et al. (see video) [3]. The aim of this study is to investigate whether this revised formula led to a reduction in over-inserted UVCs. Patients and methods In this prospective observational study, we compared the posi- tion of UVCs before and after implementation of the method with the revised formula in July 2011. In the first study period, from October 2007 to April 2008, the policy used to determine the insertion length of umbilical catheters was based on the G. H. Verheij (*) : A. B. te Pas : V. E. H. J. Smits-Wintjens : F. J. Walther : E. Lopriore Division of Neonatology, Department of Paediatrics, J6-S, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands e-mail: g.h.verheij@lumc.nl A. Šràmek Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands Eur J Pediatr (2013) 172:1011–1015 DOI 10.1007/s00431-013-1981-z