title: The effective duration of analgesia after intrathecal morphine in patients without additional opioid analgesia: a randomized double-blind multicentre study on orthopaedic patients.
abstract: OBJECTIVE
  To know whether the application of patient-controlled analgesia devices could be avoided if intrathecal morphine is given in combination with spinal anaesthesia.
  
  
  METHODS
  In a randomized, double-blind multicentre study, 188 orthopaedic patients were randomized to receive intrathecally placebo, 0.1 mg morphine or 0.2 mg morphine in addition to 15 mg bupivacaine. The primary outcome parameter was the number of patients without any additional request for opioid during a period of 72 h after surgery.
  
  
  RESULTS
  Patients with 0.1 or 0.2 mg morphine showed a significant reduction in opioid requests compared with placebo during 72 h after surgery (P = 0.0001). At 24 h after surgery, the rate of patients who required additional opioid analgesia was 71% in the placebo group, 51% in the 0.1 mg morphine group and 31% of the patients in the 0.2 mg morphine group. After 0.2 mg morphine, systemic opioid requirements at 24 h were significantly lower than those in patients with 0.1 mg morphine (P < 0.05). Intrathecal morphine was not associated with an increased frequency of respiratory depression. Forty per cent of patients with intrathecal morphine did not ask for systemic opioids.
  
  
  CONCLUSIONS
  Intrathecal morphine in a dose of 0.1 and 0.2 mg provides effective analgesia for up to 48 h without any need for systemic opioids at all in many patients.
authors.affiliation: Department of Anaesthesiology, Intensive Care Medicine and Pain Therapy, Klinikum Kassel, Kassel, Germany. gehling@klinikum-kassel.de
authors.forename: M H G
authors.initials: MH
authors.lastname: Gehling
authors.forename: T
authors.initials: T
authors.lastname: Luesebrink
authors.forename: P J
authors.initials: PJ
authors.lastname: Kulka
authors.forename: M
authors.initials: M
authors.lastname: Tryba
mesh_terms: D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D004177:Dipyrone / Q000627:therapeutic use; D004311:Double-Blind Method; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007278:Injections, Spinal; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use*; D019637:Orthopedic Procedures; D010100:Oxygen / Q000097:blood; D010147:Pain Measurement / Q000187:drug effects; D010149:Postoperative Pain / Q000188:drug therapy*; D011537:Pruritus / Q000139:chemically induced; D015656:Respiratory Mechanics / Q000187:drug effects / Q000502:physiology; D018401:Sample Size; D013997:Time Factors
chemical_list: D000701:Analgesics, Opioid; D000894:Anti-Inflammatory Agents, Non-Steroidal; D004177:Dipyrone; D009020:Morphine; D010100:Oxygen