title: Protamine overdose and its impact on coagulation, bleeding, and transfusions after cardiopulmonary bypass: results of a randomized double-blind controlled pilot study.
abstract: BACKGROUND
  We assessed the effects of protamine overdosing on thrombelastometry, bleeding, and transfusions in patients after cardiopulmonary bypass (CPB).
  
  
  METHODS
  In group 1 (n = 15), representing the clinical standard, the protamine dose was based on the initial heparin dose, and group 2 (n = 15) received protamine based on the heparin concentration measured after CPB. Primary end points were thromboelastometric parameters. Secondary end points were perioperative blood loss and utilization of blood products.
  
  
  RESULTS
  During CPB, heparin concentrations decreased by 40%, resulting in overdosing of protamine in group 1. Thromboelastometry revealed longer clotting time (CT) in group 1 (P values < .05). Four patients in group 1 but none in group 2 had excessive prolonged CT values (>360 seconds) and concomitant microvascular bleeding, requiring substantial replacement of coagulation factors.
  
  
  CONCLUSIONS
  Heparin dose-based protamine management leads to protamine overdosing with inhibition of the coagulation process. Protamine management guided by heparin concentration avoids these complications.
authors.affiliation: 1Institute for Anaesthesiology, Heart and Diabetes Centre North Rhine-Westphalia, Ruhr-University Bochum, Bad Oeynhausen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Koster
authors.forename: Jochen
authors.initials: J
authors.lastname: Börgermann
authors.forename: Jan
authors.initials: J
authors.lastname: Gummert
authors.forename: Markus
authors.initials: M
authors.lastname: Rudloff
authors.forename: Armin
authors.initials: A
authors.lastname: Zittermann
authors.forename: Uwe
authors.initials: U
authors.lastname: Schirmer
mesh_terms: D000368:Aged; D001777:Blood Coagulation / Q000187:drug effects*; D001780:Blood Coagulation Tests; D002315:Cardiopulmonary Bypass / Q000379:methods*; D004311:Double-Blind Method; D005260:Female; D006494:Heparin Antagonists / Q000506:poisoning*; D006801:Humans; D008297:Male; D010865:Pilot Projects; D011479:Protamines / Q000506:poisoning*
chemical_list: D006494:Heparin Antagonists; D011479:Protamines
keywords: anticoagulants; bleeding; blood coagulation factors; hemostasis; heparins