title: Postoperative analgesic effect of transcranial direct current stimulation in lumbar spine surgery: a randomized control trial.
abstract: BACKGROUND
  Ultimately, the experience of pain derives from changes in brain excitability. Therefore, modulating the excitability of cortical areas involved in pain processing may become an attractive option in the context of multimodal analgesia during the postoperative period. Repetitive transcranial magnetic stimulation (rTMS) can reduce morphine consumption during the postoperative period after gastric bypass surgery. We tested the potential of another method of noninvasive brain stimulation, transcranial direct current stimulation (tDCS), to reduce morphine consumption or pain perception during the postoperative period.
  
  
  METHODS
  Fifty-nine ASA I to II patients undergoing lumbar spine surgery were randomized to receive anodal (n=20), cathodal (n=20), or sham (n=19) tDCS in the recovery room in a double-blind manner. Morphine consumption administrated through patient-controlled analgesia (PCA) was the primary outcome; pain perception as measured by visual analog scale was the secondary outcome.
  
  
  RESULTS
  There were no statistically significant differences between the 3 groups of patients, either for PCA morphine consumption or for pain scores.
  
  
  CONCLUSIONS
  Several factors may explain the observed lack of impact of tDCS on PCA morphine consumption and pain perception: the method of brain stimulation (tDCS/rTMS), potential interactions with anesthetic drugs, differences in patients population (gastric bypass surgery/lumbar spine surgery), and the previous experience of pain and chronic consumption of analgesic drugs. Further studies with tDCS should be performed before concluding that tDCS is inefficient for postoperative pain control, because noninvasive brain stimulation methods, such as rTMS and tDCS, may become attractive in the setting of multimodal analgesia.
authors.affiliation: Department of Anesthesiology, CHU Mont-Godinne UCL (Universite´ catholiquede Louvain), Yvoir, Belgium.
authors.forename: Philippe E
authors.initials: PE
authors.lastname: Dubois
authors.forename: Michel
authors.initials: M
authors.lastname: Ossemann
authors.forename: Katalin
authors.initials: K
authors.lastname: de Fays
authors.forename: Pascale
authors.initials: P
authors.lastname: De Bue
authors.forename: Maximilien
authors.initials: M
authors.lastname: Gourdin
authors.forename: Jacques
authors.initials: J
authors.lastname: Jamart
authors.forename: Yves
authors.initials: Y
authors.lastname: Vandermeeren
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016058:Analgesia, Patient-Controlled; D000701:Analgesics, Opioid / Q000627:therapeutic use*; D004311:Double-Blind Method; D004599:Electric Stimulation Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008161:Lumbosacral Region / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000627:therapeutic use*; D017063:Outcome Assessment, Health Care; D010147:Pain Measurement; D010149:Postoperative Pain / Q000628:therapy*; D055815:Young Adult
chemical_list: D000701:Analgesics, Opioid; D009020:Morphine