title: A simple method for calculating component dilution during fluid resuscitation: the Leuven approach.
abstract: OBJECTIVE
  To test the reliability of the Leuven approach, a balance between oversimplified empiric rules and more complex calculations requiring the use of nomograms or computers, to determine blood component dilution during large transfusions. To present schemes for blood component dilution and stabilization, as well as four examples showing the practicability of the method.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Orthopedic operating rooms at a university hospital.
  
  
  METHODS
  108 patients undergoing total hip replacement with expected large blood loss.
  
  
  METHODS
  Component concentrations were measured after patient arrival in the recovery room. Blood loss was followed clinically.
  
  
  RESULTS
  Preset target component concentrations [hematocrit (Hct) 31%; total serum protein (TSP) 5.0 g/dl; prothrombin time (PT) 50%; blood platelets (BLPL) 50,000/microliters)] were compared with concentrations measured on arrival in recovery after dilution and stabilization, according to the transfusion scheme. Average blood loss was 3,226 +/- 1,600 ml (mean +/- SD). End component concentrations were Hct, 33.4% +/- 3.3%; TSP, 5.2 +/- 0.5 g/dl; PT, 52% +/- 12%; BLPL, 97,000/microliters. Hct and TSP showed significant (p < 0.05) but clinically unimportant differences from target concentrations. Possible reasons for variability in end concentrations are discussed.
  
  
  CONCLUSIONS
  The Leuven approach produces reliable blood component concentrations after extensive transfusions. It allows the clinician to decide for himself or herself, in accordance with general consensus and the patient's individual needs, when to stabilize blood components.
authors.affiliation: Department of Anesthesiology, University Hospitals, Katholieke Universiteit Leuven, Belgium.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Mortelmans
authors.forename: G A
authors.initials: GA
authors.lastname: Vermaut
authors.forename: H
authors.initials: H
authors.lastname: Van Aken
mesh_terms: D001769:Blood; D001779:Blood Coagulation Factors / Q000008:administration & dosage; D016063:Blood Loss, Surgical; D001798:Blood Proteins / Q000008:administration & dosage / Q000032:analysis; D001803:Blood Transfusion; D001810:Blood Volume; D005440:Fluid Therapy; D006400:Hematocrit; D006438:Hemodilution; D006622:Hip Prosthesis; D006801:Humans; D007430:Intraoperative Care; D008954:Models, Biological; D010976:Platelet Count; D017713:Platelet Transfusion; D011446:Prospective Studies; D011517:Prothrombin Time; D012769:Shock / Q000097:blood / Q000628:therapy
chemical_list: D001779:Blood Coagulation Factors; D001798:Blood Proteins