title: Perioperative complications in patients on low-molecular-weight heparin bridging therapy.
abstract: BACKGROUND
  Patients taking warfarin are often given interim anticoagulation in the perioperative period. Institutional guidelines that use low-molecular-weight heparin (LMWH) 'bridging' while the international normalized ratio (INR) is sub-therapeutic are often based on the American College of Chest Physicians Anticoagulation Guidelines.
  
  
  OBJECTIVE
  This study aims to identify if patients at a tertiary referral hospital were anticoagulated in line with these guidelines, and the incidence and nature of bleeding and thromboembolic complications.
  
  
  METHODS
  A retrospective review of the Alfred Hospital General Surgical and 'Hospital at Home' databases was conducted, identifying patients who underwent elective general surgical procedures and received bridging anticoagulation with enoxaparin. Demographics, indication for anticoagulation, bleeding and thromboembolism rates were recorded. Thromboembolic risk was estimated.
  
  
  RESULTS
  The study identified 108 patients. Three-quarters of all patients were anticoagulated with LMWH doses in accordance with the guidelines. Thirty of the 108 patients suffered bleeding complications. This group was younger, weighed less, received higher doses of enoxaparin and were at higher predicted risk of thromboembolism than non-bleeding patients. Wound haematoma, rectal bleeding and intra-abdominal bleeding were the most frequent complications. The peak time of bleeding was 3.5 days after surgery. Twelve patients returned to theatre, 13 were readmitted and 3 received blood transfusion. One patient suffered pulmonary emboli on the first post-operative day.
  
  
  CONCLUSIONS
  LMWH bridging therapy when prescribed appropriately is associated with low rates of inpatient thromboembolism in elective general surgical patients within our institution, but an unexpectedly high rate of bleeding complications.
authors: Department of Surgery, The Alfred Hospital, Melbourne, Victoria, Australia.
authors: Daniel T
authors: DT
authors: Breen
authors: Department of Surgery, The Alfred Hospital, Melbourne, Victoria, Australia.
authors: Nuttaya
authors: N
authors: Chavalertsakul
authors: Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.
authors: Eldho
authors: E
authors: Paul
authors: Department of Surgery, The Alfred Hospital, Melbourne, Victoria, Australia.
authors: Russell L
authors: RL
authors: Gruen
authors: Department of Surgery, The Alfred Hospital, Melbourne, Victoria, Australia.
authors: Jonathan
authors: J
authors: Serpell
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D006470:Hemorrhage / Q000453:epidemiology; D006495:Heparin, Low-Molecular-Weight / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D059035:Perioperative Period; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology; D017410:Practice Guidelines as Topic; D012189:Retrospective Studies; D012307:Risk Factors; D013514:Surgical Procedures, Operative / Q000009:adverse effects* / Q000379:methods* / Q000706:statistics & numerical data; D062606:Tertiary Care Centers; D013923:Thromboembolism / Q000453:epidemiology
chemical_list: D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight
keywords: blood loss; elective; heparin; low-molecular-weight; surgical; surgical procedure; thromboembolism; warfarin