title: The effect and duration of prophylactic platelet transfusions before insertion of a central venous catheter in patients with bone marrow failure evaluated with point-of-care methods and flow cytometry.
abstract: BACKGROUND
  Patients with bone marrow failure and severe thrombocytopenia are frequently given prophylactic platelet transfusion before interventions. The clinical effects of such transfusions, however, are poorly defined. We performed a prospective observational study on patients with bone marrow failure scheduled for prophylactic platelet transfusion before the insertion of a central venous catheter. The objectives were to evaluate the effect and duration of prophylactic platelet transfusions on central venous catheter insertion in thrombocytopenic patients with bone marrow failure.
  
  
  METHODS
  Thirty-nine adult patients with bone marrow failure and platelet counts below 50 × 10/L were consecutively enrolled before prophylactic platelet transfusion for subclavian central venous catheter insertion. Blood samples were drawn from the patients before platelet transfusion, 1 hour, and 4 hours after completion of the transfusion. The coagulation profile was assessed by conventional hematological tests, thromboelastometry (ROTEM) assays (EXTEM and FIBTEM), multiple electrode aggregometry (Multiplate) assays including adenosine diphosphate, collagen, and thrombin receptor agonist peptide, and by flow cytometry for the platelet expression of P-selectin (CD62P) and activated glycoprotein IIb-IIIa (PAC-1). Bleeding complications were classified with a 5-grade scale, according to the Common Terminology Criteria for Adverse Events.
  
  
  RESULTS
  Seventeen women and 22 men were included in the study. Platelet count was increased from 24 × 10/L (18-32) before to 42 × 10/L (31-50) 1 hour after transfusion (P < 0.0001) and was not significantly different 4 hours after transfusion (40 × 10/L (29-50), P = 0.047). Maximal clot firmness EXTEM was increased from 38 mm (32-45) before to 46 mm (41-52) 1 hour after transfusion (P < 0.0001) and did not change 4 hours after transfusion. Clotting time EXTEM was decreased from 58.5 seconds (50-78) beforehand to 53 seconds (45-61) 1 hour after transfusion (P = 0.0006) and was not significantly different 4 hours after transfusion (57 seconds (52-70, P = 0.025). FIBTEM results were all unchanged after transfusion. All Multiplate analyses were significantly increased after 1 hour and were not diminished 4 hours after transfusion. Four grade 1 bleeding episodes occurred, but no grade 2 to 5 bleeding could be detected. Flow cytometry analyses showed mixed results with no overall trend.
  
  
  CONCLUSIONS
  Prophylactic platelet transfusions in thrombocytopenic patients with bone marrow failure improve hemostatic parameters on ROTEM and Multiplate by increasing the number of platelets, and not through enhancement of platelet function. Improved clotting parameters on ROTEM and platelet aggregation on Multiplate appear to persist between 1 and 4 hours after transfusion.
authors.affiliation: From the Department of Intensive and Perioperative Care, Skåne University Hospital and Lund University, Lund, Sweden; Department of Anesthesiology, Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania; Clinical Chemistry, Malmö, Laboratory Medicine, Skåne, Sweden.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kander
authors.forename: Kenichi A
authors.initials: KA
authors.lastname: Tanaka
authors.forename: Eva
authors.initials: E
authors.lastname: Norström
authors.forename: Johan
authors.initials: J
authors.lastname: Persson
authors.forename: Ulf
authors.initials: U
authors.lastname: Schött
mesh_terms: D000328:Adult; D000368:Aged; D016026:Bone Marrow Transplantation / Q000379:methods / Q000592:standards*; D062905:Central Venous Catheters / Q000592:standards*; D005260:Female; D005434:Flow Cytometry / Q000379:methods / Q000592:standards*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010976:Platelet Count / Q000379:methods / Q000592:standards; D017713:Platelet Transfusion / Q000379:methods / Q000592:standards*; D019095:Point-of-Care Systems / Q000592:standards*; D013997:Time Factors; D017211:Treatment Failure; D016896:Treatment Outcome