title: Analgesic and sedative effects of intranasal dexmedetomidine in third molar surgery under local anaesthesia.
abstract: BACKGROUND
  Dexmedetomidine (DEX) is an alpha 2-adrenoreceptor agonist, which induces sedation and analgesia. This study aimed to determine whether intranasal DEX offered perioperative sedation and better postoperative analgesia.
  
  
  METHODS
  Patients having unilateral third molar surgery under local anaesthesia were recruited and allocated to receive either intranasal DEX 1 µg kg(-1) (Group D) or same volume of saline (Group P) 45 min before surgery. Patient-controlled sedation with propofol was offered as a rescue sedative. Perioperative sedation, postoperative pain relief and analgesic consumption, vital signs, adverse events, postoperative recovery, and satisfaction in sedation and analgesia were assessed.
  
  
  RESULTS
  Thirty patients from each group were studied. Areas under curve (AUC) of postoperative numerical rating scale (NRS) pain scores 1-12 h at rest and during mouth opening were significantly lower in Group D (P=0.003 and 0.009, respectively). AUC BIS values and OAA/S sedation scores were significantly lower before surgery and at the recovery area (all P<0.01) with significantly less intra-operative propofol used in group D (P<0.01). In group D, heart rate was significantly lower at recovery period (P=0.005) while systolic blood pressure in different periods of the study (all P<0.01), but the decreases did not require treatment. More patients from placebo group experienced dizziness (P=0.026) but no serious adverse event was found. No difference was found in postoperative psychomotor recovery and satisfaction in pain relief and sedation.
  
  
  CONCLUSIONS
  Patients receiving intranasal DEX for unilateral third molar surgery with local anaesthesia were more sedated perioperatively with better postoperative pain relief. No delay in psychomotor recovery was seen.
authors.affiliation: Department of Anaesthesiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong. cheucw@hku.hk
authors.forename: C W
authors.initials: CW
authors.lastname: Cheung
authors.forename: K F J
authors.initials: KF
authors.lastname: Ng
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: M Y V
authors.initials: MY
authors.lastname: Yuen
authors.forename: M H A
authors.initials: MH
authors.lastname: Ho
authors.forename: M G
authors.initials: MG
authors.lastname: Irwin
mesh_terms: D000281:Administration, Intranasal; D000293:Adolescent; D058647:Adrenergic alpha-2 Receptor Agonists / Q000494:pharmacology*; D000328:Adult; D018712:Analgesics, Non-Narcotic / Q000494:pharmacology*; D000772:Anesthesia, Local; D019540:Area Under Curve; D020927:Dexmedetomidine / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D008297:Male; D008964:Molar, Third / Q000601:surgery*; D010149:Postoperative Pain / Q000188:drug therapy*
chemical_list: D058647:Adrenergic alpha-2 Receptor Agonists; D018712:Analgesics, Non-Narcotic; D006993:Hypnotics and Sedatives; D020927:Dexmedetomidine