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In this study, boys comprised the majority of participants, which aligns with previous studies demonstrating male predominance in NICU admissions and interventions. This pattern may reflect sex-related differences in pediatric morbidity and increased vulnerability to critical illnesses among male infants [19,20]. However, evidence on sex differences in catheter duration and complications remains limited, and our findings suggest that while catheter duration tended to be longer in males, this difference was not statistically significant, aligning with prior reports indicating that sex alone does not significantly influence catheter-related outcomes [21,22].
Age and weight are important factors considered when planning vascular access in pediatrics. Our findings illustrated that most pediatric children were aged ≤ 12 months and 60 months, and weighed < 4.5 kg. A study by Wu et al. [23] found that lower gestational age and birth weight were associated with increased risk of hepatic complications following UVC use. Previous studies reported that catheter dwell time does not depend solely on neonatal age or body weight; rather, careful technique and monitoring, rather than patient size, may be more critical determinants of catheter longevity [24–26]. Importantly, the predominance of older and heavier infants in our study may have biased the observed complication rates downward, since these infants have more mature immune systems, larger vessels, and lower vulnerability compared to preterm pediatric children, a population heavily represented in previous studies reporting high complication rates. This difference in population structure is a key source of potential outcome misclassification when comparing our findings to the other studies.
We observed no major catheter-related complications, including infection, thrombosis, hematoma, pneumothorax, or hemothorax, and only two cases of minor local swelling were documented, which were not associated with deep vein thrombosis. A study by Torkaman et al. reported a 33.3% incidence of CVC-related infection in neonates, with significant associations among infection, catheter duration, and low birth weight, and noted that sepsis and hemothorax contributed to catheter-related mortality [17]. Another study by Liu et al. on central- and peripheral-line-associated bloodstream infections in 581 Victorian neonatal intensive care units reported that infections were most common in neonates ≤750 g [27]. 
The small sample size in this study may likely contribute to the markedly lower complication rate observed in this study. The absence of infection in the current study may reflect shorter catheter durations, strict adherence to aseptic insertion and maintenance protocols, and careful patient monitoring. More recently, Gibson et al. [28] demonstrated that prolonged indwelling time remained a significant risk factor for complications associated with umbilical vascular catheters. In contrast, despite relatively long dwell times (with 60% of catheters remaining in place ≥10 days), our findings demonstrated no infections. This discrepancy may be partially explained by differences in catheter type, insertion site distribution, and institutional practice patterns.
Another study by Hojsak et al. illustrated that in a 21-year cohort study of pediatric patients receiving prolonged parenteral nutrition, there were 36 episodes of catheter-related sepsis and 11 catheter removals due to infection, despite rigorous hospital protocols. They observed a significantly lower incidence of sepsis in patients receiving parenteral nutrition at home [29], highlighting the role of controlled care practices and environmental factors in infection prevention. The mean duration of catheterization in our study was longer than previously reported ones [23,30]. Buttera et al. described median dwell times of only four to five days following efforts to minimize umbilical venous catheters (UVCs) use [30], while Wu et al. [23] reported a median of around eight days.
In the current study, a mean of approximately 11 days suggests that prolonged catheter use can be achieved safely under well-controlled conditions. However, when comparing vein-specific outcomes, our results differ from those of Yang et al. [31], who found cubital and axillary veins to have longer dwell times. This may reflect differences in population age, catheter type, or institutional expertise, underscoring the importance of contextualizing findings rather than assuming universal applicability. A study by Mashhadi et al. reported that in 18 neonates with prior internal jugular catheterization, Doppler ultrasound 29 months later showed significant rates of stenosis and occlusion [32]. Because we did not perform routine post-removal ultrasonography, subclinical thrombosis or delayed complications may have been missed, further contributing to potential outcome ascertainment bias.
While other studies highlight the risks of infection and thrombosis with prolonged catheter use [11,33], our results demonstrated none. Evidence emphasized that staff training, sterile technique, and standardized catheter care bundles are strongly associated with lower complication rates [34,35]. In this study, while two cases of swelling were evaluated with ultrasound, routine imaging was not used for all patients, which raises the possibility that some subclinical complications could have gone undetected. Thus, both under-ascertainment of outcomes and the inclusion of infants and older pediatrics beyond the strict neonatal period should be considered when interpreting our unexpectedly low complication rates
As a limitation of this study, a single-center design and retrospective cross-sectional nature warrant caution in generalizing our findings. Although we found no complications related to CVC, this cannot be generalized due to the small sample size. Future studies should differentiate strictly between age groups in pediatrics to minimize population misclassification and should incorporate systematic imaging-based surveillance to reduce outcome ascertainment bias. Larger, multicenter studies with systematic complication surveillance are needed to better define the safety profile of longer catheter dwell times and evaluate how insertion site, patient characteristics, and catheter care practices interact to influence outcomes.
Our findings demonstrated that the right femoral vein was the most frequently used site for CVC insertion, followed by the right jugular vein. Importantly, no major catheter-related complications were observed, apart from two cases of local swelling without evidence of DVT. However, future studies with a larger sample size are required to confirm the safety of using CVC in pediatric patients.

Conflict of Interest
The authors declare that they have no competing interests.

Declaration of Generative Artificial Intelligence in Scientific Writing
We used AI's tools to improve the manuscript's language and grammar.