title: Viscoelastic blood coagulation measurement with Sonoclot predicts postoperative bleeding in cardiac surgery after heparin reversal.
abstract: OBJECTIVE
  The aim of the study was to determine if Sonoclot with its sensitive glass bead-activated, viscoelastic test can predict postoperative bleeding in patients undergoing cardiac surgery at predefined time points.
  
  
  METHODS
  A prospective, observational clinical study.
  
  
  METHODS
  A teaching hospital, single center.
  
  
  METHODS
  Consecutive patients undergoing cardiac surgery (N = 300).
  
  
  METHODS
  Besides routine laboratory coagulation studies and heparin management with standard (kaolin) activated clotting time, additional native blood samples were analyzed on a Sonoclot using glass bead-activated tests. Glass bead-activated clotting time, clot rate, and platelet function were recorded immediately before anesthesia induction and at the end of surgery after heparin reversal but before chest closure.
  
  
  RESULTS
  Primary outcome was postoperative blood loss (chest tube drainage at 4, 8, and 12 hours postoperatively). Secondary outcome parameters were transfusion requirements, need for surgical re-exploration, time of mechanical ventilation, length of intensive care unit and hospital stay, and hospital morbidity and mortality. Patients were categorized into "bleeders" and "nonbleeders." Patient characteristics, operations, preoperative standard laboratory parameters, and procedural times were comparable between bleeders and nonbleeders except for sex and age. Bleeders had higher rates of transfusions, surgical re-explorations, and complications. Only glass bead measurements by Sonoclot after heparin reversal before chest closure but not preoperatively were predictive for increased postoperative bleeding.
  
  
  CONCLUSIONS
  Sonoclot with its glass bead-activated tests may predict the risk for postoperative bleeding in patients undergoing cardiac surgery at the end of surgery after heparin reversal but before chest closure.
authors: Department of Anesthesiology, Institute of Anesthesiology and Intensive Care Medicine, Triemli City Hospital, Zurich, Switzerland.
authors: Dominique B
authors: DB
authors: Bischof
authors: Institute of Anesthesiology and Pain Medicine, Kantonsspital Winterthur, Winterthur, Switzerland.
authors: Michael T
authors: MT
authors: Ganter
authors: Department of Anesthesiology, Hofstra Northshore-LIJ School of Medicine, New Hyde Park, NY.
authors: Linda
authors: L
authors: Shore-Lesserson
authors: Section of Epidemiology, Vetsuisse Faculty, University of Zurich, Switzerland.
authors: Sonja
authors: S
authors: Hartnack
authors: Department of Psychiatry and Psychotherapy University Hospital, Zurich, Switzerland.
authors: Richard
authors: R
authors: Klaghofer
authors: Clinic for Cardiac Surgery, Triemli City Hospital, Zurich, Switzerland.
authors: Kirk
authors: K
authors: Graves
authors: Clinic for Cardiac Surgery, Triemli City Hospital, Zurich, Switzerland.
authors: Michele
authors: M
authors: Genoni
authors: Department of Anesthesiology, Institute of Anesthesiology and Intensive Care Medicine, Triemli City Hospital, Zurich, Switzerland. Electronic address: christoph.hofer@triemli.stzh.ch.
authors: Christoph K
authors: CK
authors: Hofer
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects / Q000627:therapeutic use*; D001777:Blood Coagulation / Q000187:drug effects* / Q000502:physiology; D001780:Blood Coagulation Tests / Q000379:methods; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D005260:Female; D006493:Heparin / Q000009:adverse effects / Q000627:therapeutic use*; D006494:Heparin Antagonists / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019106:Postoperative Hemorrhage / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D011237:Predictive Value of Tests; D011446:Prospective Studies
chemical_list: D000925:Anticoagulants; D006494:Heparin Antagonists; D006493:Heparin
keywords: anticoagulants; blood coagulation; blood coagulation tests; blood transfusion; cardiac surgical procedures; hemostasis; heparin; point-of-care systems; postoperative hemorrhage