title: Laboratory evaluation of hemostasis before cardiac operations.
abstract: BACKGROUND
  Several opinions prevail on the necessity and on the choice of laboratory coagulation tests to perform before cardiac operations. This review aims at providing simple and clinically relevant recommendations.
  
  
  METHODS
  The literature on preoperative coagulation testing was reexamined, taking into account the low prevalence of unknown and unsuspected hemorrhagic disease, and the risk of false positive results.
  
  
  RESULTS
  Carefully controlled, randomized trials are lacking but it seems appropriate to perform a few inexpensive tests (platelet count, activated partial thromboplastin time, and prothrombin time), mainly to obtain baseline values for patients who are about to undergo a major hemostatic challenge. A more complete coagulation profile (eg. bleeding time, fibrinogen concentration, thrombin time) should be considered in patients who present with a history of bleeding.
  
  
  CONCLUSIONS
  A careful medical history is the key element to detect a bleeding disorder. Only a very limited coagulation profile should be obtained in asymptomatic patients before cardiac operations.
authors.affiliation: Department of Medicine, University Hospital, Geneva, Switzerland.
authors.forename: P
authors.initials: P
authors.lastname: de Moerloose
mesh_terms: D001780:Blood Coagulation Tests; D006348:Cardiac Surgical Procedures; D006474:Hemorrhagic Disorders / Q000175:diagnosis; D006801:Humans