Pre-analytical effects of pneumatic tube system transport on routine haematology and coagulation tests, global coagulation assays and platelet function assays

Individual thrombin generation and spontaneous bleeding rate during personalized prophylaxis with Nuwiq®(human‐cl rhFVIII) in previously treated patients with severe haemophilia A

“…In addition, the International Society on Thrombosis and Haemostasis (ISTH) Subcommittee on FVIII, FIX, and Rare Coagulation Disorders recently proposed standardized conditions for presampling and measurement of thrombin generation in patients with haemophilia . Factors noted to cause variability prior to the assay being performed included use of different types of tubes for blood collection, prevention of prolonged stasis with long application (>60 s) of a tourniquet, use of corn trypsin inhibitor, transport of blood samples by hand versus pneumatic tube transport, and inappropriate preparation and storage of plasma samples . Analytical variables that should be controlled include the source and concentration of both tissue factor and phospholipids used, and assay temperature, with preheating of plates cited as an important source of variability …”

Thrombin Generation and Cirrhosis: State of the Art and Perspectives

“…Most studies reported a time interval between blood sampling and centrifugation below 2 hours, which is probably sufficiently quick to avoid any effect of prolonged storage. 23 The transportation type from the blood sampling site to the laboratory (e.g., pneumatic tube system or manual transport) can also modify the amount of thrombin generated, 24 potentially due to preactivation events, release of procoagulant PL and microvesicles by platelets, and release of TF by leucocytes, but it is not usually reported. Plasma preparation can include a single or a double centrifugation.…”

“…Although the tube type and citrate concentration are usually specified, how samples are transported to the laboratory (pneumatic tube system or hand-carrier) should also be reported because of the influence of the pneumatic tube systems on TGA. 24 Furthermore, the use (or not) of a contact phase inhibitor should be clearly mentioned, although it seems that CTI could be avoided for the TF concentrations used in studies on patients with cirrhosis. 18,21,22 The interval between sampling and centrifugation should also be specified (ideally less than 1 hour to enable the greatest sample integrity and preventing loss of labile factors such as FV and FVIII).…”

Proposal for standardized preanalytical and analytical conditions for measuring thrombin generation in hemophilia: communication from the SSC of the ISTH

“…Sensitivity of the assay to low TF concentrations (i.e. ≤ 1 pM) is increased in plasmas prepared from blood collected into contact pathway inhibitors [10][11][12][13][14][15][16][17][18][19][20][21]. Use of a low TF concentration (≤ 1 pM) can detect hypocoagulability induced by factor VIII or IX deficiency and monitor hemostatic therapies in hemophilia patients [18,22,23].…”