title: Electromyographic assessment of dexamethasone in treatment of post-tonsillectomy pain: randomized, placebo-controlled trial.
abstract: BACKGROUND
  Surface electromyographic (sEMG) study of post-tonsillectomy swallow-evoked muscular reactions was performed to assess analgesic properties of dexamethasone.
  
  
  METHODS
  Sixty randomly chosen operated adults were divided into 2 groups. Group 1 (n = 30) was treated with dexamethasone (Dexacort, 20 mg); group 2 (n = 30) was treated with placebo. Pain assessment included visual analogue scale (VAS) pain score and the EMG data such as the timing, electric amplitude and graphic patterns of muscular activity during deglutition. We investigated masseter, infrahyoid and submental-submandibular muscles. Records from trapezius muscle were used for control. The results were compared with previously established normative database. The sEMG data were compared with VAS pain score with regard to changes in clinical condition of the patients.
  
  
  RESULTS
  Surface EMG signs of analgesia after tonsillectomy did not always correspond with the VAS pain score. Dexamethasone normalizes muscular activity in deglutition as detected by the EMG records. Statistically significant difference in muscle reactions was detected between the 2 groups.
  
  
  CONCLUSIONS
  If dexamethasone is administered, the reduction of the postoperative pain could be secondary to the reduction of edema. The sEMG might be used for quantitative evaluation of analgesics via assessment of neuromuscular reactions to analgesia.
authors.affiliation: Department of Otolaryngology, Assaf Harofe Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Israel. vaimed@yahoo.com
authors.forename: Michael
authors.initials: M
authors.lastname: Vaiman
authors.forename: Eliad
authors.initials: E
authors.lastname: Aviram
authors.forename: Daniel
authors.initials: D
authors.lastname: Krakovski
authors.forename: Haim
authors.initials: H
authors.lastname: Gavriel
authors.forename: Ephraim
authors.initials: E
authors.lastname: Eviatar
mesh_terms: D000328:Adult; D000700:Analgesics / Q000008:administration & dosage / Q000627:therapeutic use*; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D003679:Deglutition; D003907:Dexamethasone / Q000008:administration & dosage / Q000627:therapeutic use*; D004487:Edema / Q000188:drug therapy; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D010147:Pain Measurement / Q000295:instrumentation / Q000379:methods*; D010149:Postoperative Pain / Q000188:drug therapy* / Q000503:physiopathology; D013997:Time Factors; D014068:Tonsillectomy / Q000009:adverse effects*; D016896:Treatment Outcome
chemical_list: D000700:Analgesics; D000893:Anti-Inflammatory Agents; D003907:Dexamethasone