title: Bedside monitoring of coagulation activation after challenging healthy volunteers with intravenous endotoxin.
abstract: BACKGROUND
  In the intensive care, many patients are at risk of developing procoagulant changes leading to severe coagulopathy and disseminated intravascular coagulation (DIC). Close monitoring of the coagulation is therefore crucial. In this study, we assess a novel bedside instrument based on free oscillating rheometry, measuring the degree of coagulation activity as clotting onset time, COT. COT measurements are conducted in whole blood, and thus reflect the overall hemostasis.
  
  
  METHODS
  Nine healthy volunteers were subjected to intravenous injection of 2 ng/kg endotoxin. To quantify the activation of the coagulation system, COT was assessed along with prothrombin fragment 1 + 2 (F1 + 2) and activated partial thromboplastin time (aPTT).
  
  
  RESULTS
  Baseline COT was 10.6 +/- 3.6 min. Three hours after endotoxin injection, maximal body temperature and heart rate were registered. At this time, an activation of the coagulation was observed as a significant decrease in COT to 8.0 +/- 1.0 min, a decrease in aPTT and increased levels of F1 + 2. COT levels, body temperature and heart rate subsequently normalized towards initial levels. F1 + 2 however continued to increase throughout the study.
  
  
  CONCLUSIONS
  COT is a rapid test, performed in less than 15 min. COT was superior to F1+ 2 in monitoring the endotoxin-induced activation of the coagulation, since COT covariated with clinical symptoms, whereas F1 + 2 did not. This is, to our knowledge, the first time an overall coagulation monitoring method has been assessed bedside to detect endotoxin-induced activation of the coagulation. The COT test shows promising results, but further studies are needed to reveal its potential in the intensive care monitoring arsenal.
authors.affiliation: Coagulation Research, Department of Surgical Sciences, Karolinska Hospital, Karolinska Institutet, S 171 76 Stockholm, Sweden. johanna.ungerstedt@mbb.ki.se
authors.forename: Johanna S
authors.initials: JS
authors.lastname: Ungerstedt
authors.forename: Anne
authors.initials: A
authors.lastname: Soop
authors.forename: Alf
authors.initials: A
authors.lastname: Sollevi
authors.forename: Margareta
authors.initials: M
authors.lastname: Blombäck
mesh_terms: D000328:Adult; D001780:Blood Coagulation Tests; D004211:Disseminated Intravascular Coagulation / Q000097:blood*; D004731:Endotoxins / Q000008:administration & dosage*; D004926:Escherichia coli; D005069:Evaluation Studies as Topic; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods*; D010314:Partial Thromboplastin Time; D010446:Peptide Fragments / Q000378:metabolism; D011516:Prothrombin / Q000378:metabolism; D011517:Prothrombin Time
chemical_list: D004731:Endotoxins; D010446:Peptide Fragments; C045879:prothrombin fragment 1.2; C044101:endotoxin, Escherichia coli; D011516:Prothrombin