Macro- and microscopic changes in veins with short-term central venous catheters: an observational autopsy study

Abstract

Background: Centrally inserted central catheters (CICCs) are indispensable in modern healthcare, but unfortunately, come with complications. Catheter-related thrombosis is a well-known complication reported to occur in 5-30% of patients with CICC. There is a paucity of studies that report the incidence of catheter-related thrombosis after the introduction of real-time ultrasound insertion guidance as clinical practice. This study aimed to demonstrate any pathological macro- or microscopic changes in the vein wall associated with CICCs.

Methods: The study was approved by the Swedish Ethical Review Authority and was conducted at a large university hospital. The study included 12 patients with a short-term CICC who were subject to autopsies. Vessels with inserted catheters were macroscopically and microscopically examined.

Results: In total, seven female and five male patients with a median age of 70 (interquartile range 63-76) were included. With one exception, all patients received routine thromboprophylaxis throughout the period with CICC. Most inserted CICCs were 9.5 French (54%) and were inserted in the internal jugular vein (92%). The median time with CICC was seven days (interquartile range 1.8-20). At autopsy, thrombi were observed in all cases (100%), macroscopically and microscopically, attached to the distal portion of the CICC and/or the adjacent vessel wall. Inflammatory changes in the vessel walls were seen in all cases, and varying degrees of fibrosis were demonstrated in eight cases (67%).

Conclusions: This autopsy study demonstrated that catheter-related thrombus formation with adjacent inflammatory and fibrotic vessel wall thickening was very common, despite a limited period of catheter use. The consequences of these findings are important, as thrombi may cause pulmonary embolism and possibly lead to catheter-related infections, and since inflammatory and fibrotic vessel wall thickening may evolve into chronic venous stenosis. Furthermore, the findings are a cause of concern, as CICCs are indispensable in modern healthcare and complications may be masked by the general disease that was the indication for CICC insertion.

Keywords: Central venous catheter thrombosis; Central venous catheterization; Complications; Vascular Endothelium; Vascular injury.

Fig. 1

Macroscopically, thrombi attached to the centrally inserted central catheter (*) and to the adjacent vessel wall (**) were observed in all cases (100%). Photographs were taken before and after formalin fixation

Fig. 2

Microscopical changes observed at autopsy in the vein wall after central venous catheterization. Panels A and B show a large microscopic thrombus (*) adherent to the vessel wall. Marked inflammation (grade 3) with cellular infiltration and oedema reaching throughout the vessel wall can be observed (**). Panel C represents a normal vessel wall, which can be compared with Panel D, demonstrating a severe degree of fibrosis with extreme thickening of the intima (***) and a marked increase in mucosal collagen (**) subjacent to the adherent thrombus (*) and a severe degree of inflammation with transmural infiltration of inflammatory cells (****)