Abstract
Thrombocytopenia is not uncommonly seen in patients undergoing peripheral blood stem cell collection. It is most likely secondary to the administration of chemotherapy and G-CSF, as well as the apheresis process itself. Peripheral blood stem cell collection causes a variable loss of platelets, which are collected along with the mononuclear cells. The ensuing thrombocytopenia can be at times severe, but the bleeding risk in this setting is unclear, as is the need to administer platelets prophylactically when the central catheter used for collection is removed. In this study we retrospectively analyzed data on 40 patients who had a central venous line removed immediately after their last autologous stem cell collection and had a platelet count of less than 50000/μL before the apheresis procedure. Patients were divided into two groups, according to whether or not they had received a platelet transfusion. The expected pre-catheter removal platelet count was calculated, according to the patient’s blood volume, the number of platelets in the stem cell product and the amount of platelets transfused in random donor platelet units (RDP) equivalents. Each chart was reviewed for the occurrence of catheter removal-associated bleeding. The results are shown in table 1. Post-apheresis platelet measurement is not routinely performed, due to its inconvenience to the patient and delay in catheter removal. Most clinicians use the pre-apheresis value as a guide to transfuse platelets before taking out the central line. As shown in table 1, in spite of significantly lower measured platelet counts before the harvest procedure in the transfused group, the calculated final counts were similar, due to the transfusion of allogeneic platelets. The patients’ weight was significantly lower in the transfused group, and this might actually have contributed to their lower platelet counts after repeated peripheral stem cell collections. There was no bleeding associated with catheter removal in either group. One patient had persistent oozing at the catheter insertion site, likely secondary to an unusually large incision. Removal was uneventful however. In this study, removing the central venous catheter was performed safely without platelet transfusion in patients who had a pre-apheresis platelet count above 30000/μL. It might be safer to administer prophylactic platelet transfusions to patients with lower counts.
Table 1 Untransfused group Transfused group P N 34 6 Patient weight in kg (median, range) 93 (52–125) 76 (63–89) 0.03 Measured platelet count pre-apheresis X 1000/μL (median, range) 40 (28–49) 24 (19–30) <0.01 Number of platelets removed X 1011 (median, range) 0.51 (0.05–1.44) 0.48 (0.14–2.34) 0.58 Number of transfused RDP equivalents per patient (median, range) 0 5 (4–6) - Calculated platelet count post-apheresis (median, range) 32 (19–44) 39 (8–45) 0.56 Number of bleeding episodes 0 0 -
CD34-POSITIVE CELL COLLECTION EFFICIENCY IN PERIPHERAL BLOOD STEM CELL HARVEST USING A SINGLE DOUBLE-LUMEN CENTRAL VENOUS CATHETER
