Tierärztliche Hochschule Hannover Vergleichende Studie zur

Publikation 3
blood flow 15 caused by the indwelling catheter. In a murine model, using real-time in
vivo imaging, thrombus formation was demonstrated 15-20 seconds after laserinduced
endothelial injury 17 . In hamsters, thrombi were detected 8 ± 1.1 min after a
trauma was set to the carotid artery by crushing the exposed vessel with a clamp.
The formed thrombi gradually embolized and disintegrated 15 ± 2.1 min after
traumatization 18 . As the onset of neurological symptoms in this case was within
minutes of the puncture, the detachment of thrombemboli must have occurred very
shortly after the procedure. Therefore, even if taking into account inter-species
variances in hemostasis, it appears unlikely that a thrombembolus originating from
endothelial damage contralaterally to the puncture site disintegrated that rapidly and
consequentially led to the infarction of the spinal vessels.
Cutaneous, subcutaneous or muscular material accumulated in the lumen of
the needle may have been introduced into the abdominal aorta whilst threading the
catheter into the vessel. Emboli may have travelled with the aortic bloodstream into
arterial branches supplying the vertebrae. The occurrence of skin tissue emboli
originating from needle punctures 19,20 or catheter fragment embolization have been
reported in studies in man 21,22 . Even though the temporal sequence would support
these explanations, skin tissue or a polyurethrane fragment would have been
detected macroscopically or histologically. Moreover, it appears unlikely that these
emboli would cause multiple arterial embolization.
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