title: Control of postoperative pain after awake craniotomy with local intradermal analgesia and metamizol.
abstract: BACKGROUND
  Pain following brain surgery is a significant problem. Infiltration of the scalp with local intradermal anesthetics was suggested for postoperative pain control but was assessed only in the first hour postoperatively.
  
  
  OBJECTIVE
  To evaluate wound infiltration with a single dose of metamizol (dipyrone) for postoperative pain control in patients undergoing awake craniotomy.
  
  
  METHODS
  This open, prospective, non-randomized observational study, conducted in anesthesiology and neurosurgical departments of a teaching hospital, included 40 patients undergoing awake craniotomy for the removal of brain tumor. Intraoperative anesthesia included wound infiltration with lidocaine and bupivacaine, conscious sedation using remifentanil and propofol, and a single dose of metamizol (dipyrone) for postoperative pain control. Outcome was assessed by the Numerical Pain Scale on arrival at the postoperative care unit, and 2, 4 and 12 hours after the end of surgery.
  
  
  RESULTS
  On arrival at the postoperative care unit, patients reported NPS scores of 1.2 +/- 1.1 in a scale of 0-10 (mean +/- SD) (median = 1, range 0-4). The scores were 0.8 +/-0.9, 0.9 +/- 0.9 and 1 +/- 0.9 at 2 hours, 4 hours and 12 hours after the end of surgery, respectively. Based on patients' complaints and NPS lower than 3, 27 patients did not require any supplementary analgesia during the first 12 postoperative hours, 11 patients required a single dose of oral metamizol or intramuscular diclofenac, one patient was given 2 mg of intravenous morphine, and one patient required two separate doses of metamizol.
  
  
  CONCLUSIONS
  Although the clinical setup prevents the use of placebo local analgesia as a control group, the results suggest the possible role of local intradermal infiltration of the scalp combined with a single dose of metamizol to control postoperative pain in patients undergoing craniotomy.
authors.affiliation: Department of Neurosurgery, Sheba Medical Center, Tel Hashomer, Israel.
authors.forename: Rachel
authors.initials: R
authors.lastname: Grossman
authors.forename: Zvi
authors.initials: Z
authors.lastname: Ram
authors.forename: Azriel
authors.initials: A
authors.lastname: Perel
authors.forename: Yakov
authors.initials: Y
authors.lastname: Yusim
authors.forename: Ruth
authors.initials: R
authors.lastname: Zaslansky
authors.forename: Haim
authors.initials: H
authors.lastname: Berkenstadt
mesh_terms: D000779:Anesthetics, Local / Q000627:therapeutic use*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D002045:Bupivacaine / Q000627:therapeutic use; D016292:Procedural Sedation; D003399:Craniotomy; D004177:Dipyrone / Q000627:therapeutic use*; D006801:Humans; D006993:Hypnotics and Sedatives / Q000627:therapeutic use; D007430:Intraoperative Care; D008012:Lidocaine / Q000627:therapeutic use; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control*; D010880:Piperidines / Q000627:therapeutic use; D015742:Propofol / Q000627:therapeutic use; D011446:Prospective Studies; D000077208:Remifentanil; D016896:Treatment Outcome
chemical_list: D000779:Anesthetics, Local; D000894:Anti-Inflammatory Agents, Non-Steroidal; D006993:Hypnotics and Sedatives; D010880:Piperidines; D004177:Dipyrone; D008012:Lidocaine; D000077208:Remifentanil; D002045:Bupivacaine; D015742:Propofol