title: Intrathecal coadministration of bupivacaine diminishes morphine dose progression during long-term intrathecal infusion in cancer patients.
abstract: OBJECTIVE
  To determine the difference in intrathecal morphine dose progression between a continuous intrathecal infusion of a morphine/bupivacaine mixture and morphine for pain relief in patients with cancer.
  
  
  METHODS
  Patients were treated with intrathecal drugs in a randomized study and followed prospectively until death.
  
  
  METHODS
  Institute for Anesthesiology, Department of Pain Treatment, University Hospital Nijmegen, St Radboud, The Netherlands.
  
  
  METHODS
  Twenty patients with cancer were selected for intrathecal treatment because of either side effects or inadequate relief during conventional pain treatment.
  
  
  METHODS
  Intrathecal drug infusion rates and medication were adjusted according to pain relief and side effects.
  
  
  METHODS
  Progression of intrathecal morphine dose during a phase of adequate analgesia in both groups following regression analysis and analysis of possible treatment related side effects.
  
  
  RESULTS
  The combination of intrathecal morphine and bupivacaine resulted in a diminished progression of the intrathecal morphine dose (slope of regression line = 0.0003 vs. 0.005, p = 0.0001) during a phase of stable analgesia in comparison with the morphine group. No serious side effects presented.
  
  
  CONCLUSIONS
  The diminished intrathecal morphine dose increase in the combination group is considered to be due to a synergistic effect of bupivacaine on the intrathecal morphine-induced antinociception. A dose increment during long-term intrathecal infusion in cancer patients appears to be related to both disease progression and tolerance phenomena.
authors.affiliation: Department of Pain Treatment, Institute for Anesthesiology, University of Nijmegen, Sint Radboud Hospital, The Netherlands. R.vandongen@anes.azn.nl
authors.forename: R T
authors.initials: RT
authors.lastname: van Dongen
authors.forename: B J
authors.initials: BJ
authors.lastname: Crul
authors.forename: J
authors.initials: J
authors.lastname: van Egmond
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000627:therapeutic use; D000779:Anesthetics, Local / Q000008:administration & dosage* / Q000627:therapeutic use; D002045:Bupivacaine / Q000008:administration & dosage* / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D004357:Drug Synergism; D005260:Female; D006801:Humans; D007278:Injections, Spinal; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage* / Q000627:therapeutic use; D009369:Neoplasms / Q000188:drug therapy*; D010166:Palliative Care; D011446:Prospective Studies
chemical_list: D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D004338:Drug Combinations; D009020:Morphine; D002045:Bupivacaine