Estimating Umbilical Venous Catheter Insertion Depth in Newborns Using Weight or Body Measurements: A Multicenter Randomized Clinical Trial

Introduction The current methods for estimating umbilical venous catheter (UVC) insertion depth, including the umbilical to nipple (Gupta) and the birth weight-based (modified Shukla) formula, have varying accuracy rates. Objectives To compare the accuracy of UVC insertion length using the birth weight-based formula versus the surface measurement formula in determining the optimal UVC tip position. Methods A multicenter randomized clinical trial was conducted across three centers, including level III neonatal intensive care units (NICUs) in the Second Cluster in Riyadh (Al-Yamama Hospital and King Fahad Medical City), as well as King Salman Armed Forces Hospital in Tabuk City, Northwestern Region, Saudi Arabia. Neonates requiring UVC insertion during their NICU admission were randomly assigned to one of two formulas: (1) the umbilicus to nipple distance in centimeters minus 1 (UN - 1) or (2) the modified Shukla weight-based formula in centimeters (3×birth weight in kg+9, divided by 2) to estimate the pre-insertion UVC depth and to determine the UVC tip position anteroposterior and lateral thoracoabdominal radiographs were taken and reviewed by a neonatologist, who was blinded to the group assignments. Data analysis was conducted using appropriate statistical methods, ensuring adherence to ethical standards. Results A total of 158 infants were analyzed, with 88 in the Gupta group and 70 in the modified Shukla group. The majority of UVC insertions (n=156, 98.7%) were performed for intravenous fluids, total parenteral nutrition (TPN), and antibiotics, while only two cases (n=2, 1.3%) involved blood exchange transfusion. The demographic and clinical data of the two groups were comparable. The Gupta method demonstrated a significantly higher rate of correct catheter placements (n=55, 62.5%) compared to the modified Shukla method (n=32, 45.7%; p=0.02). The Gupta method was particularly effective in the SGA group, with 70.0% (n=21) correct placements, compared to 42.9% (n=9) in the modified Shukla group (p=0.04). No significant differences in catheter advancement rates or fix-on measurements were observed between the two methods (p=0.59 and p=0.45, respectively). The modified Shukla group had a significantly abnormal catheter low tip position (n=23, 32.9%) compared to the Gupta group (n=13, 14.8%; p=0.02). Conclusions The Gupta method provides more accurate UVC placement, especially in SGA neonates, compared to the modified Shukla method. Both methods showed similar catheter advancement success and insertion depth, suggesting that the Gupta method may be a more reliable approach for UVC insertion in neonates. Further studies with larger sample sizes and advanced imaging techniques are needed to confirm these findings and assess long-term outcomes.