title: Intra-articular injection of warmed lidocaine improves intraoperative anaesthetic and postoperative analgesic conditions.
abstract: BACKGROUND
  Although local anaesthesia for knee arthroscopy is a well-documented procedure, arthroscopy under local anaesthesia is often interrupted because of intolerable discomfort and pain. Warming local anaesthetic solutions may increase its anaesthetic effect. We tested whether intra-articular injection of warmed lidocaine solution could improve intraoperative anaesthetic and postoperative analgesic conditions.
  
  
  METHODS
  Patients in the warmed group received 20 ml warmed (40 degrees C) lidocaine 1% intra-articularly 20 min before surgery. The patients in the control group received 20 ml room-temperature (25 degrees C) lidocaine 1% intra-articularly 20 min before surgery. During surgery, the patients reported pain on a visual analogue scale (VAS).
  
  
  RESULTS
  The median VAS pain score was 1.5 (range, 0.0-3.0) in the warmed lidocaine group and 5.0 (4.0-8.0) in the control group (P<0.001). The median intra- and postoperative analgesic requirements in the control group were significantly greater than that in the warmed group.
  
  
  CONCLUSIONS
  Warmed lidocaine injected intra-articularly provides improved intraoperative anaesthetic and postoperative analgesic conditions for patients undergoing knee arthroscopy.
authors.affiliation: Department of Anaesthesiology, Kochi Medical School, Oko-Cho, Nankoku City, Kochi, Japan. arainon@aichi-med-u.ac.jp
authors.forename: Y-C P
authors.initials: YC
authors.lastname: Arai
authors.forename: M
authors.initials: M
authors.lastname: Ikeuchi
authors.forename: K
authors.initials: K
authors.lastname: Fukunaga
authors.forename: W
authors.initials: W
authors.lastname: Ueda
authors.forename: T
authors.initials: T
authors.lastname: Kimura
authors.forename: T
authors.initials: T
authors.lastname: Komatsu
mesh_terms: D000328:Adult; D000368:Aged; D000772:Anesthesia, Local / Q000379:methods; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001182:Arthroscopy; D005260:Female; D006358:Hot Temperature; D006801:Humans; D007270:Injections, Intra-Articular; D007719:Knee Joint / Q000601:surgery; D008012:Lidocaine / Q000008:administration & dosage*; D008297:Male; D008592:Menisci, Tibial / Q000601:surgery; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods; D010149:Postoperative Pain / Q000517:prevention & control*
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine