title: Activation of blood coagulation in patients undergoing postoperative blood salvage and re-infusion of unwashed whole blood after total knee arthroplasty.
abstract: BACKGROUND
  Perioperative blood salvage is commonly used in cardiovascular surgery and has been more recently introduced in major orthopedic surgery. Limited information is available on the influence of re-infused whole blood on the hemostatic system in orthopedic patients.
  
  
  METHODS
  The aim of this study was to assess whether perioperative salvage and re-infusion of unwashed whole blood is associated with an activation of blood coagulation in patients undergoing total knee replacement. Consecutive patients receiving re-infusion were included in the study (n=13). Patients undergoing total knee replacement without perioperative blood salvage and re-infusion served as controls (n=6). In patients receiving re-infusion thrombin-antithrombin complexes (TAT), plasmin-antiplasmin complexes (PAP) and fibrinogen were assayed at the following times: before surgery (baseline), immediately before re-infusion (T0), immediately (T1), 2 h (T2) and 24 h (T3) after the end of re-infusion. In control patients blood samples were drawn at the average times corresponding to each of the sampling time in the patients receiving re-infusion. The first post-surgery LMWH dose was given within 12 h after surgery.
  
  
  RESULTS
  TAT and PAP increased after surgery both in patients receiving re-infusion and controls. An increase of TAT and PAP was observed immediately after re-infusion with respect to baseline (TAT 513.1 +/- 259.1 microg/l vs. 5.3 +/- 4.9, p<0.0001; PAP 7408.0 +/- 1892.1 microg/l vs. 461.4 +/- 217.1, p<0.0001) and to controls (TAT 60.4 +/- 26.9 microg/l, p=0.002; PAP 2208.3 +/- 1446.4 microg/l, p<0.001). The levels of TAT and PAP in patients receiving re-infusion remained high at 2 h after re-infusion compared to those of the controls (TAT 124.1 +/- 38.3 microg/l vs. 38.08 +/- 18.9, p=0.016; PAP 5690.7 +/- 1435.5 microg/l vs. 1613.9 +/- 706.0, p<0.001) and decreased 24 h thereafter. Fibrinogen level was lower in patients receiving re-infusion compared to controls.
  
  
  CONCLUSIONS
  Whole blood re-infusion is associated with an activation of blood coagulation in patients undergoing total knee replacement. The clinical relevance of this activation has to be tested in prospective studies with adequate sample size.
authors.affiliation: Centro Ortopedico Umbro, Perugia, Italy.
authors.forename: Dino
authors.initials: D
authors.lastname: Biagini
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Filippucci
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Agnelli
authors.forename: Sergio
authors.initials: S
authors.lastname: Pagliaricci
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use; D000990:Antithrombin III / Q000032:analysis / Q000378:metabolism; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D001777:Blood Coagulation; D001804:Blood Transfusion, Autologous; D017984:Enoxaparin / Q000627:therapeutic use; D005260:Female; D005340:Fibrinogen / Q000032:analysis / Q000378:metabolism; D005341:Fibrinolysin / Q000032:analysis / Q000378:metabolism; D005343:Fibrinolytic Agents / Q000032:analysis / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D010447:Peptide Hydrolases / Q000032:analysis / Q000378:metabolism; D011184:Postoperative Period; D013997:Time Factors; D000979:alpha-2-Antiplasmin / Q000032:analysis / Q000378:metabolism
chemical_list: D000925:Anticoagulants; D017984:Enoxaparin; D005343:Fibrinolytic Agents; D000979:alpha-2-Antiplasmin; C046193:antithrombin III-protease complex; D000990:Antithrombin III; D005340:Fibrinogen; D010447:Peptide Hydrolases; D005341:Fibrinolysin