title: Absence of analgesic effect of intravenous melatonin administration during daytime after laparoscopic cholecystectomy: a randomized trial.
abstract: OBJECTIVE
  To investigate whether melatonin administered intraoperatively reduced pain following laparoscopic cholecystectomy.
  
  
  METHODS
  Randomized, placebo-controlled, double-blinded study.
  
  
  METHODS
  Two surgical departments in Copenhagen.
  
  
  METHODS
  44 women between 18 and 70 years of age, who were surgical candidates for laparoscopic cholecystectomy.
  
  
  METHODS
  Patients were anesthetized by a standard protocol and received a standard multimodal postoperative analgesic regimen. Patients undergoing surgery were admitted on the day of surgery and were discharged the day after surgery. Ten mg of intravenous (IV) melatonin or placebo were administered at the time of surgical incision.
  
  
  METHODS
  Pain was assessed by a set of questionnaires documenting "pain at rest" using a visual analog scale (VAS). The use of rescue medication was recorded. Sleep quality and general well-being were measured on separate VAS scales. Sleepiness was assessed by the Karolinska Sleepiness Scale.
  
  
  RESULTS
  Forty-four patients were included and randomized to the study. Three patients did not complete the study. No differences in VAS pain scores, sleep quality, general well-being, or sleepiness were found between the two groups in the postoperative period. The use of postoperative rescue medication did not differ between the groups.
  
  
  CONCLUSIONS
  The use of 10mg of IV melatonin administered during laparoscopic cholecystectomy did not affect postoperative pain or use of analgesic medication.
authors.affiliation: Department of Surgery D, Herlev Hospital, University of Copenhagen, DK-2730 Herlev, Denmark. Electronic address: lphandersen@gmail.com.
authors.forename: Lars Peter Holst
authors.initials: LP
authors.lastname: Andersen
authors.affiliation: Department of Surgery D, Herlev Hospital, University of Copenhagen, DK-2730 Herlev, Denmark.
authors.forename: Bülent
authors.initials: B
authors.lastname: Kücükakin
authors.affiliation: Multidisciplinary Pain Center 7612, Neuroscience Center, Rigshospitalet, University of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Mads U
authors.initials: MU
authors.lastname: Werner
authors.affiliation: Department of Surgery D, Herlev Hospital, University of Copenhagen, DK-2730 Herlev, Denmark.
authors.forename: Jacob
authors.initials: J
authors.lastname: Rosenberg
authors.affiliation: Department of Surgery D, Herlev Hospital, University of Copenhagen, DK-2730 Herlev, Denmark.
authors.forename: Ismail
authors.initials: I
authors.lastname: Gögenur
mesh_terms: D000328:Adult; D000368:Aged; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage*; D017081:Cholecystectomy, Laparoscopic; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D007432:Intraoperative Period; D008550:Melatonin / Q000008:administration & dosage*; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods; D010149:Postoperative Pain / Q000517:prevention & control*; D012890:Sleep / Q000187:drug effects; D055815:Young Adult
chemical_list: D018712:Analgesics, Non-Narcotic; D008550:Melatonin
keywords: Analgesia: multimodal postoperative; Laparoscopic cholecystectomy; Melatonin