Abstract:
To assess the feasibility and performance of ultrasound-guided midline catheters in term and preterm neonates requiring prolonged intravenous therapy without an indication for central access, and to generate hypotheses on factors influencing catheter outcomes. Single-center prospective observational cohort: 70 consecutive neonates received 2-Fr polyurethane midline catheters in a level IV NICU (March 2024-November 2025). Data were analyzed descriptively; complication-free survival was estimated by Kaplan-Meier, and exploratory subgroup comparisons used Fisher’s exact test. Mean weight at insertion was 2582 g (range 700-4920), including very low-birth-weight infants. Median dwell time was 9 days (range 0-176), corresponding to 1144 catheter-days. The primary composite outcome (complication-free dwell ≥ 7 days or elective removal before day 7) was met in 94.3% of devices. Kaplan-Meier complication-free survival was 98.6% at 3 days and 81.2% at 14 days. Device-related complications occurred in 21.4%, predominantly minor and resolving after removal. Bloodstream infection and thrombosis rates were 2.62 and 0.87 per 1000 catheter-days; no thrombophlebitis occurred. Complication rates did not differ by vein diameter < 2 mm or weight < 1500 g, although the study was underpowered for these comparisons.
Conclusion: In this pilot study, ultrasound-guided midline catheters were feasible in neonates, including very low-birth-weight infants and those with small-caliber veins, with predominantly minor complications. These hypothesis-generating findings require confirmation in adequately powered; comparative studies before midlines can be recommended as an alternative to central access or repeated peripheral cannulation.
What is known: Midline catheters may offer an intermediate option between peripheral and central venous access, but neonatal experience, particularly in preterm infants, is limited. Data on the feasibility and performance of midline catheters in the NICU are scarce.
What is new: In this single-center pilot cohort of 70 neonates, ultrasound-guided midline catheters achieved a high rate of complication-free dwell time, with predominantly minor, self-limiting complications. Complication rates did not appear to increase in infants < 1500 g or with veins < 2 mm; these hypothesis-generating observations require confirmation in adequately powered studies.
Reference:Zanetto L, Zamunaro A, Nardo D, Divisic A, Della Torre F, Salvadori S, Baraldi E, Bonadies L. Ultrasound-guided midline catheters in the neonatal intensive care unit: a single-center pilot study. Eur J Pediatr. 2026 Jul 2;185(7):547. doi: 10.1007/s00431-026-07218-5. PMID: 42390693.
