title: Intraoperative Hydroxyethyl Starch and its Effects on Different Fibrinogen Measurements.
abstract: BACKGROUND
  Intravenous fluids with synthetic colloids such as hydroxyethyl starch (HES) are known to interfere with plasma fibrinogen concentration measurements. The aim of this study was to evaluate the effects of an HES solution on fibrinogen measurements in a clinical setting.
  
  
  METHODS
  The study was performed in patients who received at least 1 L of HES during intracranial tumor resection surgery. Blood samples were drawn before the start of surgery (baseline), after infusion of 1 L of HES, and at later time points. The fibrinogen concentration was measured using 3 different methods: (a) enzyme-linked immunosorbent assay (ELISA), (b) Clauss method with a photometric readout, and (c) Clauss method with an electromechanical readout. In addition, the fibrin-based clot quality was evaluated with the thromboelastometric FIBTEM test.
  
  
  RESULTS
  Forty patients were enrolled, and 25 patients were included in the analysis. The fibrinogen concentrations at baseline were 2.2, 2.3, and 2.6 g/L and after 1 L of HES 1.6, 1.7, and 1.9 g/L as measured by ELISA, the photometric test, and the electromechanical test, respectively. The electromechanical Clauss test measured significantly higher concentrations at these time points. The relative decrease, however, was comparable between methods (31%, 29%, and 25%, respectively) but significantly lower than the 44% relative decrease with FIBTEM maximum clot firmness.
  
  
  CONCLUSIONS
  Despite providing different fibrinogen concentration values at baseline, the relative decrease in fibrinogen concentration after HES infusion was comparable among the 3 tests. In contrast, fibrin-based clot quality was more affected than fibrinogen concentration tests by HES infusion.
authors.affiliation: Department of Anaesthesia and Intensive Care, Skåne University Hospital Lund, Lund, Sweden Division of Anaesthesia and Intensive Care, Department of Clinical Sciences, Lund University, Lund, Sweden dag.winstedt@med.lu.se.
authors.forename: Dag
authors.initials: D
authors.lastname: Winstedt
authors.affiliation: Department of Anaesthesiology, Perioperative Medicine and General Intensive Care, Paracelsus Medical University, Salzburg, Austria CSL Behring, Marburg, Germany Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Centre, Vienna, Austria.
authors.forename: Cristina
authors.initials: C
authors.lastname: Solomon
authors.affiliation: Division of Anaesthesia and Intensive Care, Department of Clinical Sciences, Lund University, Lund, Sweden Clinical Chemistry and Transfusion Medicine, Halland County Hospital, Sweden.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hillarp
authors.affiliation: Division of Anaesthesia and Intensive Care, Department of Clinical Sciences, Lund University, Lund, Sweden Clinical Chemistry and Transfusion Medicine, Halland County Hospital, Sweden.
authors.forename: Tom
authors.initials: T
authors.lastname: Lundahl
authors.affiliation: Department of Anaesthesia and Intensive Care, Skåne University Hospital Lund, Lund, Sweden Division of Anaesthesia and Intensive Care, Department of Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: Ulf
authors.initials: U
authors.lastname: Schött
mesh_terms: D003430:Cross-Sectional Studies; D005260:Female; D005340:Fibrinogen / Q000494:pharmacology*; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology*; D007430:Intraoperative Care; D008297:Male; D008875:Middle Aged; D013916:Thrombelastography / Q000379:methods*
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D005340:Fibrinogen
keywords: clauss method; fibrinogen; hydroxyethyl starch derivatives; thrombelastography