[Catheter-induced thromboses--duplex ultrasound studies of incidence and extent].

The aim of the study was to detect the frequency and the extension of thrombosis caused by central venous catheters by means of Doppler-duplex ultrasound. 36 patients were examined. The visualization rate of catheters in jugular (91%) and femoral (62%) veins was excellent. In contrast, catheters in the subclavian vein could be detected only in 33 per cent of all cases. As a result the overall patency rate of catheters was only 37 per cent after a period between 8 hours and 60 days (12.2 +/- 11.3 days) following the introduction. There was no significant relation between the type of catheter, the management with central venous catheters and the rate of thrombosis.