Platelets

This study aims to compare Neutrophil to Lymphocyte and Platelet Ratio, Procalcitonin, and Total Leucocyte Count as indicators of prognostic outcome in septic patients in the intensive care unit.

The Auto-PLTS Study is a single-centre trial performed at Toronto General Hospital (TGH) that uses a randomized, patient preference design. The recent introduction of cold-stored platelets with a shelf-life of 14 days into clinical practice has made it possible to offer autologous apheresis platelet predonation to patients undergoing elective cardiac (and other high-blood-loss) surgeries while allowing sufficient time to recover platelet count before surgery. The Auto-PLTS Study is designed to assess whether replacing allogeneic platelets with autologous platelets will improve patient outcomes and benefit the healthcare system by reducing the burden on allogeneic platelet supply. The study is also designed to determine whether patients are willing to donate autologous platelets 7-10 days prior to surgery.

The investigators would like to analyze platelet/leukoplak activation, quantify and morphologically characterize these aggregates using in vitro analysis, directly on whole blood from adult patients with suspected HIT. This would enable to better describe the in vivo pathophysiology of the HIT-suspect patient, and eliminate the need for platelet donors to perform the usual confirmatory techniques, whose inter- and intra-individual variability is very high. What's more, the SRA test, evaluated as the reference test, requires the use of radioisotopes and is therefore only carried out in a few biological expertise centers, resulting in a very long delay in the delivery of results. It should also be noted that, in practice, HÉPARINE is immediately stopped in patients with suspected HIT, and they are put on an expensive anticoagulant (DANAPAROIDE SODIQUE or ARGATROBAN) in curative doses until the results of the confirmatory tests are back. In this serious, life-threatening condition, it is essential to have a sensitive, specific test to confirm HIT as quickly as possible. Each patient with suspected HIT (rapid \>30% reduction in platelet count after initiation of heparin therapy) should have 4 tubes of 3.2% citrated whole blood (2.7ml) collected at the time of suspected HIT (D0) and before any therapeutic switch (or 24 h max after switch). A new sample (4 citrated tubes) will be taken at D4, D7 and D14 during hospitalization, in patients who test positive for anti-PF4/H Ac. All patients with suspected HIT will follow the standard diagnostic pathway, i.e. a screening test (immunological test for anti-PF4/heparin antibodies, total Ig, ACL TOP, Werfen) followed by a confirmatory test (platelet aggregation on TA-8V, STAGO and/or SRA). Doppler ultrasonography of the lower limbs will be performed in HIT-suspect patients with a positive anti-PF4/H antibody test, as currently performed as part of routine care.

Cardiac surgery is a bleeding-risk surgery and frequently requires blood transfusion. Intraoperative autotransfusion devices are used to aspirate, process and retransfuse patients' blood. These devices are effective in recovering red blood cells and limiting the need for transfusion of packed red blood cells. Some devices, such as I-SEP's SAME®, can also be used to recover platelets, but their effectiveness has not yet been evaluated in real-life situations. The aim of this study is therefore to investigate the evolution of platelet counts following the use of an intraoperative recovery device in adult patients undergoing standard cardiac surgery