title: Propofol at conscious sedation doses produces mild analgesia to cold pressor-induced pain in healthy volunteers.
abstract: OBJECTIVE
  To determine whether subanesthetic doses of propofol have analgesic effects in healthy volunteers.
  
  
  METHODS
  Prospective, double-blind, placebo-controlled, randomized, crossover trial.
  
  
  METHODS
  Human psychomotor performance laboratory within our anesthesia and critical care department.
  
  
  METHODS
  12, non-drug abusing volunteers, aged 22 to 38 years.
  
  
  METHODS
  Five drug conditions were used in which a loading injection was followed by a 20-minute infusion period: placebo [saline (Intralipid)] injection, Intralipid infusion; propofol 0.125 mg/kg injection, propofol 12.5 mcg/kg/min infusion; propofol 0.25 mg/kg injection, propofol 25 mcg/kg/min infusion; propofol 0.5 mg/kg injection, propofol 50 mcg/kg/min infusion; fentanyl 1.4 mcg/kg injection (positive control), Intralipid infusion. Five minutes into the infusion period and 115 minutes after the infusion period was terminated, subjects immersed their forearms in ice-cold water for three minutes while pain assessments were recorded.
  
  
  RESULTS
  Propofol at the two higher doses during part of the first immersion produced a significant reduction (p < 0.05) in pain intensity and bothersomeness ratings. However, relative to fentanyl, the analgesia was mild. Propofol did not affect any ratings on the 15-item short-form McGill Pain Questionnaire, whereas fentanyl reduced 10 of the ratings.
  
  
  CONCLUSIONS
  Our laboratory results are consistent with the commonly accepted clinical practice of supplementing propofol with an opioid in conscious sedation procedures to provide a satisfactory level of pain relief.
authors.affiliation: Department of Anesthesia and Critical Care, University of Chicago 60637, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Zacny
authors.forename: D W
authors.initials: DW
authors.lastname: Coalson
authors.forename: C J
authors.initials: CJ
authors.lastname: Young
authors.forename: J M
authors.initials: JM
authors.lastname: Klafta
authors.forename: J L
authors.initials: JL
authors.lastname: Lichtor
authors.forename: G
authors.initials: G
authors.lastname: Rupani
authors.forename: P
authors.initials: P
authors.lastname: Thapar
authors.forename: J L
authors.initials: JL
authors.lastname: Apfelbaum
mesh_terms: D000328:Adult; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000494:pharmacology*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000494:pharmacology*; D003080:Cold Temperature; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D007101:Immersion; D007275:Injections, Intravenous; D008297:Male; D010147:Pain Measurement / Q000187:drug effects*; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D011446:Prospective Studies
chemical_list: D018686:Anesthetics, Intravenous; D000894:Anti-Inflammatory Agents, Non-Steroidal; D006993:Hypnotics and Sedatives; D015742:Propofol