Behaviour of platelets and β-thromboglobulin

Platelet count, platelet aggregation responses, and plasma β-thromboglobulin were assessed before and at intervals during each study dialysis. As expected, modest thrombocytopenia was observed following treatment with all dialysers, but Filtral showed the least effect. Concordantly, modest increases in plasma β-thromboglobulin were observed with all devices except Filtral (caveat: the device also seems to adsorb β-thromboglobulin). Interpatient variability was more striking for platelet aggregation responses, and made it difficult to discern patterns; however, aggregation in response to ADP was augmented during haemodialysis with the Filtral device, and blunted when the G120 M was employed. Differences between hollow-fibre and parallel plate devices with the same membrane material suggest that membrane geometry, manufacturing residues, membrane support, or potting materials may also contribute to platelet activation.