title: Testing of a new pneumatic device to cause pain in humans.
abstract: BACKGROUND
  Surgical pain typically combines superficial and deep pain. We wished to generate pain that resembled surgical pain, reliably and reproducibly, in volunteers.
  
  
  METHODS
  We constructed a computer-controlled pneumatic device to apply pressure to the anterior tibia. The reproducibility of the pain was tested by rating the pressure that caused pain rated 4-5 on a visual analogue scale (VAS) on days 0, 7, and 24 in 10 volunteers. The effect of remifentanil (0.025, 0.05, 0.075, and 0.1 microg kg-1 min-1) on pain tolerance in another set of volunteers (n=11) was used as an indirect measure of the reliability of pain production.
  
  
  RESULTS
  The pressure needed (0.7 (0.3) to 0.9 (0.4) atm (mean (SD)) to induce pain rated 4-5 (VAS) did not vary, showing long-term reproducibility of the method. When pressure was applied to cause increasing pain in volunteers (n=11) 0.05 microg kg-1 min-1 remifentanil increased pain tolerance by 50%. An approximate doubling of the dose (0.1 microg kg-1 min-1) increased pain tolerance significantly more. The linear logarithmic dose-effect relationship shows that the device causes pain reliably, and this can be reduced with opioid treatment.
  
  
  CONCLUSIONS
  This pneumatic device can apply pain reliably and reproducibly.
authors.affiliation: Department of Trauma Surgery and Sports Medicine, University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria. heinrich.schubert@uibk.ac.at
authors.forename: H M
authors.initials: HM
authors.lastname: Schubert
authors.forename: I H
authors.initials: IH
authors.lastname: Lorenz
authors.forename: F
authors.initials: F
authors.lastname: Zschiegner
authors.forename: C
authors.initials: C
authors.lastname: Kremser
authors.forename: M
authors.initials: M
authors.lastname: Hohlrieder
authors.forename: M
authors.initials: M
authors.lastname: Biebl
authors.forename: C
authors.initials: C
authors.lastname: Kolbitsch
authors.forename: P L
authors.initials: PL
authors.lastname: Moser
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D004867:Equipment Design; D006801:Humans; D007262:Infusions, Intravenous; D008279:Magnetic Resonance Imaging; D008297:Male; D010146:Pain / Q000503:physiopathology*; D017288:Pain Threshold; D010880:Piperidines / Q000008:administration & dosage; D011312:Pressure; D000077208:Remifentanil; D015203:Reproducibility of Results; D013977:Tibia
chemical_list: D000701:Analgesics, Opioid; D010880:Piperidines; D000077208:Remifentanil