title: The platelet-rich plasma clot: a standardized in-vitro clot formation protocol for investigations of sonothrombolysis under physiological flows.
abstract: No agreement exists about which protocol for in-vitro clot formation is suitable for sonothrombolysis investigations. Lysis rates vary considerably because of different clotting processes and cannot be compared. We aim to establish a new protocol for in-vitro coagulation to permit standardized sonothrombolysis investigations. The proposed procedure is based upon clots prepared from platelet-rich plasma (PRP). This clot material (group A) was compared with the two most commonly used procedures, namely, recalcification of citrate-anticoagulated whole venous blood (group B) and spontaneous clotting of nonanticoagulated venous blood (group C). Histological examinations were performed and clot stability was tested under physiological flow conditions in vitro for all groups (each n = 10). Lysis rates measured by mass loss were compared using buffered plasma and recombinant tissue plasminogen activator (60 kU/ml), or buffered plasma alone. PRP clots displayed a high degree of similarity to emboli specimens in histological examinations and remained stable under pulsatile flow conditions. B and C clots were mechanically unstable and did not resist physiological flow and pressure. Measuring the lysis rate by weighing seems to be inaccurate, with lowest variability in PRP clots. PRP clots appeared more resistant to lysis. PRP clots should be used for standardized sonothrombolysis investigations.
authors.affiliation: Department of Neurology, Universitätsklinikum Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, Lübeck, Germany. florian.roessler@neuro.uni-luebeck.de
authors.forename: Florian C
authors.initials: FC
authors.lastname: Roessler
authors.forename: Marcus
authors.initials: M
authors.lastname: Ohlrich
authors.forename: Jan H
authors.initials: JH
authors.lastname: Marxsen
authors.forename: Florian
authors.initials: F
authors.lastname: Stellmacher
authors.forename: Andreas
authors.initials: A
authors.lastname: Sprenger
authors.forename: Carl-Erik
authors.initials: CE
authors.lastname: Dempfle
authors.forename: Günter
authors.initials: G
authors.lastname: Seidel
mesh_terms: D001777:Blood Coagulation; D006801:Humans; D007700:Kinetics; D008954:Models, Biological; D010477:Perfusion / Q000379:methods; D053657:Platelet-Rich Plasma / Q000502:physiology*; D012015:Reference Standards; D012107:Research Design / Q000592:standards*; D015912:Thrombolytic Therapy / Q000379:methods* / Q000592:standards