Incidence and risk factors of subclinical umbilical catheter-related thrombosis in neonates.

INTRODUCTION

This study aimed to determine the risk factors for subclinical umbilical catheter-related thrombosis (UCRT) and its association with clinical morbidities.

MATERIALS AND METHODS

In infants without any symptoms associated with umbilical catheterization, the presence of thrombosis was monitored using abdominal ultrasonography within 1 week after umbilical catheter removal. The association between UCRT and the clinical variables was analyzed by comparing the groups with and without UCRT.

RESULTS

UCRT occurred in 26 (19.0%) of 137 infants. The relative incidence rate of thrombosis was 12.3% at the umbilical artery and 21.7% at the umbilical vein. However, the type of umbilical vessels with a catheter was not associated with thrombosis (P = 0.095). Subclinical UCRT was associated with high serum calcium concentration in the multivariate analysis (95% confidence interval, 1.26-15.32; P = 0.020). UCRT was resolved within 3 weeks in 13 infants (50.0%), although the thrombosis persisted for up to 2 months in 2 infants (7.7%). We found no significant association between the subclinical UCRT and the neonatal morbidities in preterm infants.

CONCLUSIONS

Though a rare cause of thrombosis, hypercalcemia should be considered in the assessment of infants with subclinical UCRT, and calcium levels should be routinely checked in infants with umbilical catheters.