title: Preoperative plasma fibrinogen concentration, factor XIII activity, perioperative bleeding, and transfusions in elective orthopaedic surgery: A prospective observational study.
abstract: BACKGROUND
  Major orthopaedic surgery involves a calculated risk of bleeding. In other groups of surgical patients, low preoperative plasma fibrinogen concentration and factor XIII (FXIII) activity have been associated with an elevated risk of bleeding. In the present study we investigated the association between preoperative fibrinogen plasma concentration and FXIII activity on bleeding and transfusion requirements in patients undergoing a spinal fusion procedure or hip or knee arthroplasty.
  
  
  METHODS
  Two hundred and forty-five adult patients undergoing spine fusion surgery (n=52), total unilateral primary hip arthroplasty (n=114), or total knee arthroplasty (n=79) were included in a prospective observational study. Blood samples were collected <24h before surgery and analysed for fibrinogen concentration and FXIII activity. Intraoperative and postoperative bleeding volume and transfusion requirements were recorded.
  
  
  RESULTS
  Spinal fusion surgery patients with a low preoperative fibrinogen concentration (≤2.5g/L) had a greater total perioperative median bleeding volume than patients with fibrinogen>2.5g/L (2430 (400-6560) mL vs. 1390 (400-7420) mL, p=0.029). No significant association between low fibrinogen levels and perioperative bleeding volume was observed for arthroplasty patients. There was no association between low fibrinogen levels and transfusion requirements in any of the groups. Low FXIII activity was not significantly associated with bleeding volume and transfusion requirements in any group.
  
  
  CONCLUSIONS
  Measurement of preoperative fibrinogen plasma concentration can identify spinal fusion patients with an increased risk of excessive perioperative bleeding. Measurement of FXIII activity cannot identify orthopaedic patients with elevated risk of bleeding.
authors.affiliation: Department of Orthopaedics, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Orthopaedics, Institute of Clinical Science, Sahlgrenska Academy University of Gothenburg, Gothenburg, Sweden. Electronic address: malin.carling@gmail.com.
authors.forename: Malin S
authors.initials: MS
authors.lastname: Carling
authors.affiliation: Department of Orthopaedics, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Orthopaedics, Institute of Clinical Science, Sahlgrenska Academy University of Gothenburg, Gothenburg, Sweden. Electronic address: josef.zarhoud@vgregion.se.
authors.forename: Josef
authors.initials: J
authors.lastname: Zarhoud
authors.affiliation: Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. Electronic address: anders.jeppsson@vgregion.se.
authors.forename: Anders
authors.initials: A
authors.lastname: Jeppsson
authors.affiliation: Department of Orthopaedics, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Orthopaedics, Institute of Clinical Science, Sahlgrenska Academy University of Gothenburg, Gothenburg, Sweden. Electronic address: b.eriksson@orthop.gu.se.
authors.forename: Bengt I
authors.initials: BI
authors.lastname: Eriksson
authors.affiliation: Department of Orthopaedics, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Orthopaedics, Institute of Clinical Science, Sahlgrenska Academy University of Gothenburg, Gothenburg, Sweden. Electronic address: helena.brisby@vgregion.se.
authors.forename: Helena
authors.initials: H
authors.lastname: Brisby
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects; D016063:Blood Loss, Surgical / Q000517:prevention & control*; D001803:Blood Transfusion; D017558:Elective Surgical Procedures / Q000009:adverse effects; D005176:Factor XIII / Q000032:analysis*; D005260:Female; D005340:Fibrinogen / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000009:adverse effects*; D059035:Perioperative Period; D011446:Prospective Studies; D013131:Spine / Q000002:abnormalities / Q000601:surgery
chemical_list: D005340:Fibrinogen; D005176:Factor XIII
keywords: Arthroplasty; Factor XIII; Fibrinogen; Haemorrhage; Orthopaedic surgery; Spinal fusion