title: Tourniquet time affects postoperative complications after knee arthroplasty.
abstract: OBJECTIVE
  Pneumatic tourniquets are frequently used in knee arthroplasty surgery. However, there is a lack of evidence to define safe tourniquet time in lower limb surgery. The primary aim of this study was to investigate whether tourniquet time influences the risk of postoperative complications after primary and secondary knee arthroplasty.
  
  
  METHODS
  This study was a prospective register study. Since we wanted dispersion in tourniquet time, we included a consecutive series of 577 primary knee arthroplasties, 46 revision knee arthroplasties, and 18 patellar supplementing knee arthroplasties from a clinical audit database over a period of five years. The following postoperative complications were recorded: superficial wound infections, deep wound infections, deep vein thrombosis, pulmonary embolism, nerve injuries, compartment syndrome, cuff pressure injuries, and bandage injuries.
  
  
  RESULTS
  Tourniquet time over 100 minutes was associated with an increased risk of complications after knee arthroplasty surgery (OR 2.2, CI 1.5-3.1). This increase in risk remained after adjusting for cuff pressure, sex, age, American Society of Anesthesiologists (ASA) classification, smoking, diabetes, and surgery indication (OR 2.4, CI 1.6-3.6).
  
  
  CONCLUSIONS
  Tourniquet time over 100 minutes increases the risk of complications after knee arthroplasty surgery and special attention is advocated to reduce the tourniquet time.
authors: Section of Orthopedics, Department of Clinical Science and Education, Södersjukhuset Karolinska Institutet, Stockholm, Sweden. charlotta.olivecrona@sodersjukhuset.se
authors: Charlotta
authors: C
authors: Olivecrona
authors: Lasse J
authors: LJ
authors: Lapidus
authors: Lina
authors: L
authors: Benson
authors: Richard
authors: R
authors: Blomfeldt
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D011183:Postoperative Complications / Q000209:etiology*; D011446:Prospective Studies; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014111:Tourniquets / Q000009:adverse effects*