Thrombus calcification after removing peripherally inserted central catheters in extremely preterm infants

Abstract

Pericatheter thrombus calcification is a complication that arises due to central venous catheter insertion and is particularly rare in peripherally inserted central catheters (PICCs). In this case report, we reviewed the clinical course of two neonates experiencing thrombus calcification. The first case involved a male neonate weighing 445 g. His PICC dwelt in the superior vena cava for over 49 days. Although a radiograph after removal did not show any silhouette, subsequent radiographs and CT depicted a catheter-like outline. Percutaneous intravascular retrieval was performed to salvage the object. Pathological examination revealed it to be a calcified cast. The calcified thrombosis was successfully dissolved with 6 months of warfarin therapy. The second case involved a male neonate weighing 534 g. After PICC removal, a catheter-like structure was shown on ultrasonograms. It was determined that invasive procedures were unnecessary for diagnosing the calcified thrombosis based on experience with the first case.

Keywords: Neonatal and paediatric intensive care; Pathology; Radiology; Unwanted effects / adverse reactions; Venous thromboembolism.

Figure 1

Cropped radiographs of the right chest. (A) The plain radiograph shows the presence of a peripherally inserted central catheter (PICC) (black arrows) in the right subclavian vein (SCV) and superior vena cava (SVC). (B) The radiograph 4 days after uneventful PICC removal does not show a linear opacity in the right SCV and SVC. (C) The radiograph 36 days after PICC removal describes a catheter-like structure (black arrows) in the right SCV and SVC, but its silhouette is slightly coarser than the catheter seen on figure 1A.

Figure 2

Plain CT of the thorax 36 days after peripherally inserted central catheter removal. Selected soft tissue window coronal slice demonstrates a linear radiopaque density (black arrows) located in the right subclavian vein and superior vena cava, which corresponds to the finding on figure 1C.

Figure 3

Transthoracic ultrasonogram with a linear 12 MHz transducer. The ultrasonogram on the right subclavian area reveals a hyperechoic, slightly crooked linear structure in the longitudinal view of superior vena cava (white arrows).

Figure 4

Pathological examination of the linear object obtained by endovascular retrieval. (A) Low-power field HE stain. B High-power field HE stain. The obtained specimen shows a lump of red blood cells (RBCs) covered with a layer composed of calcification (Cal) and fibrinous materials (Fib). The retained structure was diagnosed as thrombus calcification based on the pathological findings.

Figure 5

Cropped radiographs of the chest. (A) The radiograph shows a peripherally inserted central catheter (PICC) placed in the innominate vein and the left subclavian vein (SCV) (black arrows). (B) The radiograph after PICC replacement demonstrates a new PICC inserted in the right SCV and superior vena cava (SVC) (white arrows). Meanwhile, radiographic opacification cannot be seen in the place where the used PICC was placed (innominate vein and left SCV).

Figure 6

Transthoracic ultrasonogram with a linear 18 MHz transducer. (A) The ultrasonogram on the left peri-clavicle area delinates a linear hyperechoic density with slightly coarse surface (black arrow) in the longitudinal view of innominate vein, suggesting a calcified cast. (B) The ultrasonogram on the right subclavian area shows a linear hyperechoic density with smooth surface (white arrow) in the longitudinal view of the right subclavian vein, describing an indwelling peripherally inserted central catheter.