title: Massive transfusion and coagulopathy: pathophysiology and implications for clinical management.
abstract: OBJECTIVE
  To review the pathophysiology of coagulopathy in massively transfused, adult and previously hemostatically competent patients in both elective surgical and trauma settings, and to recommend the most appropriate treatment strategies.
  
  
  METHODS
  Medline was searched for articles on "massive transfusion," "transfusion," "trauma," "surgery," "coagulopathy" and "hemostatic defects." A group of experts reviewed the findings.
  
  
  RESULTS
  Coagulopathy will result from hemodilution, hypothermia, the use of fractionated blood products and disseminated intravascular coagulation. The clinical significance of the effects of hydroxyethyl starch solutions on hemostasis remains unclear. Maintaining a normal body temperature is a first-line, effective strategy to improve hemostasis during massive transfusion. Red cells play an important role in coagulation and hematocrits higher than 30% may be required to sustain hemostasis. In elective surgery patients, a decrease in fibrinogen concentration is observed initially while thrombocytopenia is a late occurrence. In trauma patients, tissue trauma, shock, tissue anoxia and hypothermia contribute to the development of disseminated intravascular coagulation and microvascular bleeding. The use of platelets and/or fresh frozen plasma should depend on clinical judgment as well as the results of coagulation testing and should be used mainly to treat a clinical coagulopathy.
  
  
  CONCLUSIONS
  Coagulopathy associated with massive transfusion remains an important clinical problem. It is an intricate, multifactorial and multicellular event. Treatment strategies include the maintenance of adequate tissue perfusion, the correction of hypothermia and anemia, and the use of hemostatic blood products to correct microvascular bleeding.
authors.affiliation: Department of Anesthesiology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montréal, Québec, Canada. jean-francois.hardy@umontreal.ca
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Hardy
authors.forename: Philippe
authors.initials: P
authors.lastname: De Moerloose
authors.forename: Marc
authors.initials: M
authors.lastname: Samama
mesh_terms: D000328:Adult; D001778:Blood Coagulation Disorders / Q000209:etiology* / Q000628:therapy*; D001803:Blood Transfusion / Q000379:methods*; D006801:Humans; D065227:Transfusion Reaction