Background: Umbilical venous catheters (UVCs) are associated with thrombus formation. Most studies on thrombosis in infants with UVCs focus on only one part of the route, and none assessed a control group of infants without UVCs.
Objective: To determine the incidence and location of thrombi in infants after umbilical catheterisation and compare this with a control group of infants without umbilical catheters.
Design: Prospective observational study with serial ultrasonography of the UVC route from the umbilico-portal confluence to the heart. Ultrasonography was performed until day 14 after catheterisation in cases and day 14 after birth in controls.
Results: Thrombi in the UVC route were detected in 75% (30/40) of infants with UVCs in the study group, whereas no thrombi were detected in the control group of infants without UVCs (0/20) (p<0.001). Six thrombi (20%) were located in the right atrium. Most of these were also partly present in the ductus venosus. Six thrombi (20%) were located in the ductus venosus only, and in 12 infants (40%), the thrombus was at least partly located in the umbilico-portal confluence. Thrombi persisted after UVC removal in 25/30 cases. Two infants with thrombotic events were treated with low-molecular-weight heparin and resolution was found. In the other 23 infants managed expectantly, 2 died due to necrotising enterocolitis, 1 was lost to follow-up and in 20 spontaneous regression was seen.
Conclusions: Thrombotic events occur frequently in infants after umbilical catheterisation. Most thrombi were asymptomatic and regressed spontaneously with expectant management. Routine screening for thrombi in UVCs is therefore not advised.
Keywords: clinical procedures; neonatology.
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