title: Effect of pre-emptive hydromorphone administration on postoperative pain relief--a randomized controlled trial.
abstract: OBJECTIVE
  Pre-emptive analgesia represents a treatment strategy which tries to prevent the development of pain by inhibiting central reactions to peripheral sensory stimuli. In a prospective randomized double-blind placebo-controlled study, the effect of oral premedication with 4 mg of a slow-release hydromorphone preparation on postoperative piritramide consumption and subjective pain perception is being evaluated.
  
  
  METHODS
  96 women undergoing hysterectomy were randomly assigned to four study groups. Patients from groups 1 and 2 received hydromorphone and placebo respectively two hours before surgery, while those from groups 3 and 4 were given the same substances one hour after the end of the operation. Postoperative pain relief was provided by a patient-controlled infusion pump with piritramide. The intensity of postoperative pain as perceived by the patients was quantified on a visual analogue scale. Piritramide consumption and pain scores were recorded at 1 and 24 hours after surgery. Approval of the local Ethics Committee had been obtained beforehand as well as written informed consent from the patients.
  
  
  RESULTS
  No significant differences in piritramide consumption were observed in between the four study groups. Visual analogue scale (VAS) ratings at 1 and 24 hours after surgery did not show any significant differences either--irrespective of whether the patients had received hydromorphone or placebo preoperatively or postoperatively.
  
  
  CONCLUSIONS
  In our study, oral administration of 4 mg of slow-release hydromorphone did not show any greater pre-emptive analgesic effect than placebo.
authors.affiliation: Department of Anaesthesiology and General Intensive Care, University Hospital, Vienna, Austria. ana.kopp@univie.ac.at
authors.forename: A
authors.initials: A
authors.lastname: Kopp
authors.forename: D
authors.initials: D
authors.lastname: Wachauer
authors.forename: K H
authors.initials: KH
authors.lastname: Hoerauf
authors.forename: E
authors.initials: E
authors.lastname: Zulus
authors.forename: W J
authors.initials: WJ
authors.lastname: Reiter
authors.forename: H
authors.initials: H
authors.lastname: Steltzer
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D016058:Analgesia, Patient-Controlled; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D006801:Humans; D004091:Hydromorphone / Q000008:administration & dosage* / Q000009:adverse effects; D007044:Hysterectomy; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D010892:Pirinitramide / Q000008:administration & dosage / Q000009:adverse effects; D011292:Premedication; D011446:Prospective Studies
chemical_list: D003692:Delayed-Action Preparations; D010892:Pirinitramide; D004091:Hydromorphone