Thrombocytopenia and altered platelet kinetics associated with prolonged pulmonary-artery catheterization in the dog

Effect of blood access on the platelets of azotemic patients initiating dialysis therapy

The effect of blood access on platelets and clotting factors was investigated in 46 azotemic patients. Arteriovenous fistula was used in 10 patients (AVF group), and polyurethane double-lumen catheters were inserted through the subclavian vein in 6 patients (PUS group) or through the femoral vein in 15 patients (PUF group). Indwelling urokinase-immobilized single-lumen catheters and double-lumen catheters were placed in the femoral vein of 5 patients (UKS group) and 10 patients (UKD group), respectively. Blood cell counts, beta-thromboglobulin (beta-TG), platelet factor 4 (PF4), prothrombin time, and activated partial thromboplastin time were measured before insertion while catheters were indwelling and after catheters were pulled out. Although the platelet count decreased to 83% of the initial value during indwelling in the PUF group and 89% in the PUS group, it did not decrease in the AVF, UKS, and UKD groups. There were no differences between the PUF and PUS groups nor between the UKS and UKD groups. Plasma beta-TG increased in the PUF and UKD groups with indwelling catheters but did not change with the AVF. From these results, we conclude that the AVF did not activate platelets, the urokinase-immobilized catheter activated platelets, and the polyurethane catheter activated and decreased platelets. This might be due to the different surface properties of each blood access. Thus, the urokinase-immobilized catheter seems to be more favorable than the polyurethane catheter for emergency blood access.