title: Free oscillation rheometry detects changes in clot properties in pregnancy and thrombocytopenia.
abstract: Improved methods are needed to identify patients at risk for thrombotic or bleeding events. Free oscillation rheometry (FOR) is a technique that offers information on coagulation, based on contributions of all blood components, by measurement of clotting time and changes in clot elasticity. This is the first study that evaluates FOR parameters in subjects likely to represent hypercoagulability (pregnant women) and hypocoagulability (thrombocytopenic patients). Clotting time and blood clot elasticity were measured by FOR in blood samples obtained from women in different pregnancy trimesters (n = 58), in thrombocytopenic patients before and after a platelet transfusion (n = 20) and in healthy blood donors (n = 60). The clotting time was shorter and the clot elasticity higher in pregnant women compared to the non-pregnant female blood donors. The elasticity was higher in late pregnancy compared to early pregnancy. Compared to the blood donors, the thrombocytopenic patients had lower elasticity, which was increased by a platelet transfusion, but there was no difference in clotting time. The results suggest that FOR can provide new information on the haemostatic status of patients at risk of thrombotic or bleeding events as well as information on the haemostatic effect of a platelet transfusion.
authors.affiliation: Department of Clinical Immunology & Transfusion Medicine, University Hospital, Linkoping, Sweden.
authors.forename: Nahreen
authors.initials: N
authors.lastname: Tynngård
authors.forename: Tomas L
authors.initials: TL
authors.lastname: Lindahl
authors.forename: Sofia
authors.initials: S
authors.lastname: Ramström
authors.forename: Tuulia
authors.initials: T
authors.lastname: Räf
authors.forename: Olof
authors.initials: O
authors.lastname: Rugarn
authors.forename: Gösta
authors.initials: G
authors.lastname: Berlin
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use; D001780:Blood Coagulation Tests / Q000295:instrumentation / Q000379:methods*; D001809:Blood Viscosity; D003018:Clot Retraction; D003131:Combined Modality Therapy; D004548:Elasticity; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D018056:Hemorheology / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007938:Leukemia / Q000097:blood / Q000150:complications / Q000188:drug therapy / Q000601:surgery; D008223:Lymphoma / Q000097:blood / Q000150:complications / Q000188:drug therapy / Q000601:surgery; D008297:Male; D008875:Middle Aged; D017713:Platelet Transfusion; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000097:blood* / Q000628:therapy; D011264:Pregnancy Trimesters / Q000097:blood; D012306:Risk; D013921:Thrombocytopenia / Q000097:blood* / Q000209:etiology / Q000628:therapy; D019851:Thrombophilia / Q000097:blood*