title: Effects of fibrinogen and platelet supplementation on clot formation and platelet aggregation in blood samples from cardiac surgery patients.
abstract: BACKGROUND
  Bleeding after cardiac surgery may be caused by surgical factors, impaired haemostasis, or a combination of both. Transfusion of blood products is used to improve haemostasis, but little is known about what combination is optimal. We hypothesized that addition of both fibrinogen and platelets to blood samples from cardiac surgery patients would improve clot formation and platelet aggregation to a greater extent than if the components were added separately.
  
  
  METHODS
  Increasing doses of fibrinogen concentrate (+0.5, 1.0, and 1.5 g · l(-1)) and/or platelet concentrate (+46, 92, and 138 × 10(9) platelets l(-1)) were added to postoperative blood samples from 15 cardiac surgery patients. Clot formation was assessed with rotational thromboelastometry and platelet aggregation was assessed with multiple-electrode aggregometry before and after addition of the blood products. The effects of the different additives were compared.
  
  
  CONCLUSIONS
  Ex vivo supplementation with fibrinogen or platelet concentrate resulted in significantly shortened clotting time and improved clot strength in a dose-dependent manner. Combination of fibrinogen and platelets further improved the clotting time and strength. Platelet supplementation enhanced platelet aggregation in a dose-dependent manner while fibrinogen had no or reducing effect. Combining fibrinogen and platelets improved platelet aggregation less than the use of platelets alone. In conclusion, combined platelet and fibrinogen supplementation of blood samples from cardiac surgery patients had an additive effect on clot formation compared to the individual components, but it resulted in less platelet aggregation than with platelet supplementation alone. These results may have implications for clinical transfusion protocols.
authors.affiliation: Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, SE-413 45 Gothenburg, Sweden. Electronic address: caroline.hakimi@gmail.com.
authors.forename: Caroline
authors.initials: C
authors.lastname: Shams Hakimi
authors.affiliation: Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden. Electronic address: inger.fagerberg.blixter@vgregion.se.
authors.forename: Inger
authors.initials: I
authors.lastname: Fagerberg Blixter
authors.affiliation: Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, SE-413 45 Gothenburg, Sweden. Electronic address: emma.hansson@vgregion.se.
authors.forename: Emma C
authors.initials: EC
authors.lastname: Hansson
authors.affiliation: Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden. Electronic address: camilla.hesse@biomedlab.gu.se.
authors.forename: Camilla
authors.initials: C
authors.lastname: Hesse
authors.affiliation: Karolinska Institute, Department of Clinical Sciences, Danderyd Hospital, SE-182 88 Stockholm, Sweden. Electronic address: hakan.wallen@ds.se.
authors.forename: Håkan
authors.initials: H
authors.lastname: Wallén
authors.affiliation: Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, SE-413 45 Gothenburg, Sweden; Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden(3). Electronic address: anders.jeppsson@vgregion.se.
authors.forename: Anders
authors.initials: A
authors.lastname: Jeppsson
mesh_terms: D000368:Aged; D001777:Blood Coagulation; D001780:Blood Coagulation Tests; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D005340:Fibrinogen / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D010974:Platelet Aggregation; D010979:Platelet Function Tests; D017713:Platelet Transfusion; D019106:Postoperative Hemorrhage / Q000097:blood / Q000209:etiology / Q000628:therapy*; D013916:Thrombelastography
chemical_list: D005340:Fibrinogen
keywords: Aggregometry; Cardiac surgery; Clot formation; Fibrinogen; Platelets