title: The use of pneumatic tourniquets is safe in Asians undergoing total knee arthroplasty without anticoagulation.
abstract: BACKGROUND
  There has always been controversy surrounding the use of pneumatic tourniquets in total knee arthroplasty (TKA) as they have been implicated in venous thromboembolic events (VTE). We aimed to evaluate the incidence of clinically significant VTE in Asians who underwent conventional TKA under tourniquet throughout the duration of surgery, without post-operative chemical VTE prophylaxis, but using post-operative pneumatic compression devices.
  
  
  METHODS
  Five hundred and thirty-one patients of a single surgeon who underwent elective total knee arthroplasty were retrospectively reviewed. All patients had a tourniquet applied to the operated limb. None of the patients received chemoprophylaxis against VTE. Post-operatively, only symptomatic patients were referred for ultrasonography. The patients were then stratified according to the tourniquet time: <60, 61 to 90, 91 to 120, and >120 min. The overall incidence as well as the incidence of venous thromboembolic events for each group was then calculated.
  
  
  RESULTS
  Of the 531 patients reviewed, 3 patients suffered from deep venous thrombosis (DVT) while 1 patient developed a fatal pulmonary embolism (PE). Hence, the overall incidence of clinically significant VTE was 0.75%. The 3 patients with DVT had tourniquet time of 61 to 90 min while the patient with PE had a tourniquet time of more than 120 min.
  
  
  CONCLUSIONS
  With a low overall incidence of VTE, the use of tourniquet in Asians during conventional total knee arthroplasty appears safe when post-operative pneumatic compression devices are used instead of chemical VTE prophylaxis. However, the risk of VTE seems to increase with a tourniquet time of more than 60 min.
  
  
  METHODS
  Therapeutic studies, level III.
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, Outram Road, 169608, Singapore. Electronic address: hamidrazak@gmail.com.
authors.forename: Hamid Rahmatullah
authors.initials: HR
authors.lastname: Bin Abd Razak
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, Outram Road, 169608, Singapore.
authors.forename: Hwee Chye Andrew
authors.initials: HC
authors.lastname: Tan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D044466:Asian People; D015992:Body Mass Index; D005260:Female; D006801:Humans; D048228:Intermittent Pneumatic Compression Devices; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D011183:Postoperative Complications / Q000517:prevention & control; D011655:Pulmonary Embolism / Q000209:etiology*; D012189:Retrospective Studies; D013997:Time Factors; D014111:Tourniquets / Q000009:adverse effects*; D020246:Venous Thrombosis / Q000209:etiology*
keywords: Total knee arthroplasty; Tourniquet; Venous thromboembolism