Prophylaxis of port system-associated thromboses in advanced oncology patients using heparin flushing.
Ключови думи
Резюме
OBJECTIVE
Thromboses occur in connection with the use of venous port systems. Valid data on the instillation of heparin-based solutions in the lumen of the port system are lacking.
METHODS
One hundred and seventy-three patients with malignancy from 19 centres who had participated in an observation study of subcutaneous thromboprophylaxis with dalteparin-Na (Fragmin P/-Forte) were analysed with a view to flushing the port systems and investigating any related influence on the occurrence of catheter-associated thromboses.
RESULTS
All catheter-associated thromboses were seen in centres which used either no UFH, or UFH concentrations of up to 250 IU/ml (8/108; 7.4%). The rate of thrombosis rose to 10% (6/60) if no high-risk dose of dalteparin was applied subcutaneously. On the other hand, the rate of catheter-associated thromboses under the high-risk dose of dalteparin and/or a more highly concentrated instillation fluid, at 0.9% (1/113), was much lower. One haemorrhage from gastric ulcer occurred under the highest UFH concentration in the instillation fluid (2,500 IU UFH/ml).
CONCLUSIONS
The results indicate that a concentration between 500 IU UFH/ml and 1,000 IU UFH/ml in the instillation solution, at the same time as high-risk prophylaxis with subcutaneous dalteparin for prevention of catheter-associated thromboses, is effective in patients with manifest tumour disease. The instillation of LMWH-based solutions at a concentration of approx 500 anti-Xa units/ml should be discussed as a pending issue.
