Exploring Neonatal Length, Weight, Post-Menstrual Age, and Peripherally Inserted Central Catheter Depth

Peripherally inserted central catheters (PICCs) have become universal in the care of neonatal patients. The use of an infant's length, weight, or post-menstrual age (PMA) may be an alternative method for measuring the depth of a PICC.

The purpose of this study was to explore the relationships among neonatal length, weight, PMA, and PICC depth.

Inpatient neonates admitted to a Nationwide Children's Hospital's Newborn Intensive Care Unit requiring placement of PICC were enrolled between January 2022 and April 2024. Standard PICC procedures were maintained. The research group corroborated appropriate PICC tip position of enrolled infants. Multivariable linear regression with robust standard errors was used to evaluate linear relationships between PICC insertion depth and current weight, current length, and PICC insertion site.

Birth demographics of enrolled infants had gestational ages of 22 to 41 weeks, weights of 450to 4160 g, and lengths of 25.5 to 54.6 cm. Of the 182 infants enrolled, 72 underwent antecubital, 71 ankle, and 39 knee insertions. Three models were analyzed: current length, current weight, and PMA, demonstrating a significant association with PICC depth (P < .0001). Infant length proved to be the strongest predictor of PICC depth.

This investigation provides an alternative method of measurement for estimating centimeter length of neonatal PICC depth. Further examination into the data by stratifying an infant's weight and length and/or gestational age may prove to be a more appropriate prediction model.