Finding the most suitable puncture site for intraosseous access in term and preterm neonates: an ultrasound-based anatomical pilot study

Abstract

The purpose of this prospective ultrasound-based pilot study was to identify the most suitable tibial puncture site for intraosseous (IO) access in term and preterm neonates, describe tibial dimensions at this site, and provide anatomical landmarks for rapid localization. We measured the tibial dimensions and distances to anatomical landmarks at puncture sites A (proximal: 10 mm distal to the tibial tuberosity; distal: 10 mm proximal to the malleolus medialis) and B (chosen by palpation of the pediatrician), in 40 newborns in four weight groups (< 1000 g; 1000-2000 g, 2000-3000 g, and 3000-4000 g). Sites were rejected if they fell short of the assumed safety distance to the tibial growth plate of 10 mm. If both A and B were rejected, puncture site C was determined sonographically at the maximum tibial diameter while maintaining the safety distance. Puncture site A violated the safety distance in 53% and 85% (proximally and distally, respectively) and puncture site B in 38% and 33%. In newborns weighing 3000-4000 g, at median (IQR), the most suitable puncture site at the proximal tibia was 13.0 mm (12.0-15.8) distal to the tuberosity and 6.0 mm (4.0-8.0) medial to the anterior rim of the tibia. The median (IQR) diameters at this site were 8.3 mm (7.9-9.1) (transverse) and 9.2 mm (8.9-9.8) (anterior-posterior). The diameters increased significantly with increasing weight. Conclusion: This study adds concise, practical information on the implementation of IO access in neonatal patients: the tibial dimensions in newborns in four different weight groups and initial data on anatomical landmarks to easily locate the IO puncture site. The results may help implement IO access in newborns more safely. What is Known: • Intraosseous access is a feasible option for emergency administration of vital drugs and fluids in newborns undergoing resuscitation when an umbilical venous catheter is impossible to place. • Severe complications of IO access due to malpositioned IO needles have been reported in neonates. What is New: • This study reports the most suitable tibial puncture sites for IO access and the tibial dimensions, in newborns of four weight groups. • The results can help to implement safe IO access in newborns.

Keywords: Anatomical landmarks; Intraosseous access; Neonatal resuscitation; Newborns; Puncture site; Tibial dimensions.

Fig. 1

Illustrative example of the ultrasound protocol and markings in a preterm neonate, gestational age 30 + 3, of weight group 1000–2000 g

Fig. 2

Illustrative example of ultrasound measurement in a term infant with a body weight of 3195 g at the a) proximal tibia and b) distal tibia

Fig. 3

Measured distances of A and B marks to the growth plate at the a) proximal tibia and b) distal tibia. Each dot represents one measurement. The lineplots represent means (± 1 se) per group and visualize the differences between age groups for suggested (A, black) and pediatrician-determined (B, grey) puncture sites. The scattered line represents the safety distance of 10 mm. Indications are in mm (standard deviation)

Fig. 4

Boxplot of tibial diameters at the optimal puncture sites for four weight groups at the a) proximal tibia and b) distal tibia. Significant pairwise differences are marked by asterisks (*p < 0.05; **p < 0.01; ***p < 0.001). Outliers are represented as dots with numeric values. Indication in mm