Platelets perform a vital role in the haemostatic procedure as a way to seal affected blood vessels. The platelets form a platelet plug at the weakened area and avoid blood loss. After the injury to the vessel wall has been taken care of, the platelets withdraw the coagulum, enabling the blood circulation freely in the vessel. Free oscillation rheometry (FOR) may be utilized for evaluation of coagulation as calculated by clotting time and changes in clot elasticity (G’). Clot G’ offers info on the fibrin network in the coagulum and the platelets’ capability to retract the coagulum. Free oscillation rheometry Free oscillation rheometry FOR analysis is conducted making use of the ReoRox® 4 instrument. The blood sample is added to a cylindrical sample cup, that is set into free oscillation. The frequency and damping of the oscillation is documented over time as the blood coagulates. The change in G’ is calculated from the frequency and damping recorded. Patients with malignant haematological diseases in many cases are thrombocytopaenic and need platelet transfusions to avoid or stop bleeding. To make sure good haemostatic function in the recipient it is essential that the quality of the platelets utilized for transfusion is well maintained. The purpose of this project report was to figure out the quality of platelet concentrates (PCs), during storage, using various in vitro methods, including Free oscillation rheometry FOR, and also to look into how different preparation processes impact the quality. We also researched whether or not Free oscillation rheometry FOR may be applied to assess the haemostatic status in subjects vulnerable to thrombosis or bleeding in addition to how the haemostatic status was impacted by a platelet transfusion. We demonstrate that FOR can offer information on the coagulation properties in subjects vulnerable to thrombosis (pregnant women) or bleeding (thrombocytopaenic patients).
Contents: Free oscillation rheometry in the assessment of platelet quality
INTRODUCTION
HISTORY OF BLOOD TRANSFUSION
PLATELETS
Integrins
GPIb
GPVI
P-selectin
G-protein coupled receptors
HAEMOSTASIS
Primary haemostasis
Secondary haemostasis
Clot retraction
Fibrinolysis
PLATELET TRANSFUSIONS
Preparation and storage of platelet concentrates
Platelet metabolism
TRANSFUSION REACTIONS
Febrile nonhaemolytic
Haemolytic
Alloimmunisation
Transfusion-related acute lung injury
Transfusion-associated graft-versus-host disease (TA-GVHD)
Transfusion-transmitted bacteraemia/sepsis
QUALITY TESTING OF PLATELET CONCENTRATES
Bleeding time
Blood gases
Metabolic parameters
Swirling
Hypotonic shock response (HSR)
Platelet activation
Aggregation
AIMS OF THE THESIS
METHODOLOGY
FREE OSCILLATION RHEOMETRY (FOR)
Comparison of FOR and thromboelastography
FLOW CYTOMETRY
ANALYTICAL PROCEDURES
FOR ANALYSIS…
Free oscillation rheometry in the assessment of platelet quality Downloads
Source: Linköping University
Download URL 2: Visit Now